SP-4103 Model Research - Volume 2


Appendix H (3/4)




[665] 27. Joseph S. Ames to F. H. LaGuardia, 24 Feb. 1932.


[Congressman Fiorello H. LaGuardia was an aviation enthusiast and a friend of the NACA. When it was proposed in the early 1930s to transfer the NACA to the Department of Commerce, LaGuardia asked the committee for ammunition to fight the move. In this letter, NACA Chairman Joseph Ames employed the defenses characteristic of the Committee: he cited the practical uses made of the Committee's researches, the economies it had effected, and the endorsements of its clients.]


My dear Mr. LaGuardia:

In response to your request of February 22, I am enclosing a copy of the Seventeenth Annual Report of the National Advisory Committee for Aeronautics, blue-penciled to indicate the principal activities of the organization, and also a memorandum relating to the present and future need of continuing the Committee.

The opposition the Committee has had in the past has not been formidable nor direct, with a single exception, and that was the action in December, 1925, by the Department of Commerce, not appreciating the real functions of the Committee, in incorporating in the original Senate draft of the Air Commerce Act of 1926 a section transferring the Committee to the Department of Commerce and making the Assistant Secretary of Commerce for Aeronautics Chairman of the Committee. That was approved by the Senate Committee on Commerce without the knowledge of the National Advisory Committee nor of the War or Navy Departments. After the bill was ordered favorably reported, one member of the Senate committee was apprised of the opposition of the War and Navy Departments and polled his colleagues, with the result that the bill was actually reported with a committee amendment striking out the objectionable section.

Aside from this incident, there has been no move by any committee of Congress to change the status of the National Advisory Committee since it was created as an independent establishment in 1915; nor has there been any effort other than that of the editor of the magazine Aero Digest, Mr. Frank A. Tichenor, who suggests that the National Advisory Committee for Aeronautics be eliminated "through the simple process of merging it with the Bureau of Standards." This reckless suggestion now current is made by one who is not familiar with the real functions of the Committee in coordinating the work of the Bureau of Standards, along with that of other agencies of the Government concerned with aeronautics. Furthermore, the author of the suggestion has never to our knowledge visited the Committee's laboratories, and has no evident qualifications to evaluate the results of scientific investigations in aeronautics.

The Committee as a coordinating agency in aeronautics brings about the efficient use of the facilities of all agencies of the Government. On fundamental problems relating to aeronautics the Committee is a clearing house for the Army, the Navy, the Department of Commerce, and also the aircraft industry.

The Committee has received many voluntary expressions from aeronautical authorities, including the most competent engineers in the aircraft industry, complimenting the organization on its effective work. For your information I am enclosing some extracts showing some of the viewpoints of others.

The National Advisory Committee for Aeronautics is not only an effective agency for coordination and prevention of duplication in the field of aeronautical research, but is also a service agency, serving the needs of the other governmental agencies concerned with aeronautics. It is a recognized principle in governmental organization that coordinating agencies and service agencies should remain independent.

[666] The air organizations of the War and Navy Departments rely upon the Advisory Committee for the scientific knowledge and fundamental information that underlie progress in military and naval aircraft. The Department of Commerce and the aircraft industry are necessarily dependent also upon the Committee for the scientific investigation and study of fundamental problems.

The Government expends each year millions of dollars for the purchase of new aircraft for the Army and Navy and other millions through the Department of Commerce and the Post Office Department to promote the civil and commercial use of aircraft. The future of civil aviation is dependent upon the development of safer and more efficient types of aircraft. The increasing importance of aircraft for military and naval purposes makes it necessary that America have the most up-to-date and efficient aircraft. This means that America must keep abreast of other nations in the scientific development of the airplane.

It is not a matter of chance that at the present time the United States is at the forefront of progressive nations in the development of military and commercial avia-tion. It is the result of persistent and continuous research that has made it possible for American designers to develop aircraft of superior qualities.

I consider it a very serious matter to disturb the present status of the Committee as an independent establishment, as this status is largely responsible for its success. Any disturbance in status will affect adversely the efficiency of the organization and will undermine the very foundations of our aeronautical development.

The membership of the National Advisory Committee for Aeronautics includes seven governmental representatives from the War and Navy Departments, the Bureau of Standards, the Weather Bureau, and the Smithsonian Institution, and eight persons appointed from private life, all of whom serve as such without compensation. Its organization embraces eight principal committees and seven subcommittees, totaling 85 members, who also serve without compensation. It is evident, therefore, that this Committee represents the best thought of every group concerned with the technical development of aircraft.

I beg to assure you that I appreciate greatly your interest in the whole field of aeronautics and especially your interest in giving our Committee an opportunity to explain to you our point of view.


Sincerely yours,



..."Some Reasons Why the National Advisory Committee for Aeronautics Should be Continued as an Independent Government Establishment."

"Some Comments on the Work of the National Advisory Committee for Aeronautics."


February 24, 1932.




Reference: Current Suggestion to Transfer the National Advisory Committee for Aeronautics to the Department of Commerce and to Merge It with the Bureau of Standards.

1. The National Advisory Committee for Aeronautics is at present an independent Government establishment created by law in 1915, charged with the duty of supervis-ing and directing the scientific study of the problems of flight. This function is extraneous to the major purpose of any other governmental agency.

[667] 2. The Committee is an effective agency for coordination and prevention of duplication in the field of aeronautical research. It is a recognized principle that coordinating agencies should be independent.

3. The Committee is a service agency, serving the needs of all governmental agencies concerned with aeronautics. It is a recognized principle that service agencies should be independent.

4. Military, naval, and commercial aviation are under the War, Navy, and Commerce Departments respectively. There can be no question that the technical activities of the Aeronautics Branch of the Department of Commerce and of its Bureau of Standards should be coordinated with those of the War and Navy Departments. The National Advisory Committee for Aeronautics could not continue to coordinate effectively the activities of the War, Navy, and Commerce Departments relating to aeronautical research if the Committee were under the control of either of those departments.

5. For the Advisory Committee to discharge its duties efficiently and deal fairly and impartially with technical matters it should remain an independent establishment.

6. The War, Navy, and Commerce Departments now have representation on the National Advisory Committee for Aeronautics. To place the Committee under the control of the Department of Commerce would give a dominating influence to its representative, would have the effect of denying equality to the other members, and ultimately would destroy the value of the Committee as an impartial coordinating agency.

7. The natural and certain consequence would be that the air services of the Army and Navy would cease to rely upon the Advisory Committee as they do now for the scientific study and solution of the more fundamental problems of flight, and would follow their own independent lines of endeavor, which would result in duplication, waste, and inefficiency and retard progress in military and naval aircraft development.

8. The Advisory Committee would cease to be a "national" advisory committee for aeronautics and would become merely an advisory committee for civil and commercial aeronautics under and for the Department of Commerce.

9. The Committee membership includes representatives from all governmental agencies concerned with the development of aeronautics and eminent scientists and aeronautical authorities from private life, including such men as Dr. Joseph S. Ames, President of Johns Hopkins University (Chairman); Dr. David W. Taylor, former Chief Constructor of the Navy (Vice Chairman); Dr. William F. Durand, of California, an eminent consulting engineer; Dr. Orville Wright, the inventor of the airplane; Honorable Edward P. Warner, former Assistant Secretary of the Navy for Aeronautics; Honorable William P. MacCracken, Jr., former Assistant Secretary of Commerce for Aeronautics; Honorable Harry F. Guggenheim, former President of the Daniel Guggenheim Fund for the Promotion of Aeronautics, Incorporated; and Colonel Charles A. Lindbergh. All the members serve as such without compensation. The dignity of membership on the Committee in its present status of an independent establishment and the satisfaction that comes from service rendered in a truly patriotic devotion to duty constitute the only compensation of the members. This made possible the fact expressed by President Coolidge in 1924 that "through this Committee the talent of America has been marshaled in the scientific study of the problems of flight, with the result that America occupies a position in the forefront of progressive nations in the technical development of aeronautics. The status of the Committee as an independent Government establishment has largely made possible its success."

10. To deny the Committee a continuance of its present independent status would inevitably lead to lowering of the caliber of its membership. The Committee could not long expect to hold the confidence of the Army and Navy air services nor exert the same healthy influence as in the past. The inevitable result would be the dissolution of the Committee and the loss to the nation of the organization which has been primarily [668] responsible for the leading position taken by America in connection with aeronautical research. This position must be maintained if we are to continue to be in advance of all other nations in the technical development of aircraft.




"Through this committee the talent of America has been marshaled in the scientific study of the problems of flight, with the result that today America occupies a position in the forefront of progressive nations in the technical development of aeronautics. The status of the committee as an independent Government establishment has largely made possible its success."- Calvin Coolidge, President, U.S., The White House, Washington, D.C., Dec. 8, 1924, letter to Congress

Dwight W. Morrow, chairman of the President's Aircraft Board, in referring to the testimony presented at their Hearings said "- it is interesting to note that the aviation work of the Post Office Department and of the Advisory Committee for Aeronautics practically escaped all criticism." - Dwight W. Morrow (Letter to Dr. Ames Dec. 22, 1925)

The National Advisory Committee is an excellent example of the way to accomplish results, that is to say, by a permanent body of men largely from within the service who know the work and who have authority. The Committee has accomplished real results not only in the coordination of the work of various Government branches interested in aeronautics, but in bringing them into closer contact with the public. The Committee's work has been of the greatest value in aiding and encouraging the aircraft industry." - Dr. S. W. Stratton, former Director of the Bureau of Standards, October 27, 1923

"Your reports every year are better and better in every way. They contain, in my opinion, scientific material of quite as high a value as anything produced at the National Physical Laboratory (British) or Göttingen (German aeronautical laboratory). They are infinitely clearer in presentation than any British reports..."- New York University, Alexander Klemin, Professor of Aeronautics, April 4, 1924

".....your committee is most helpful and authoritative. You are doing a great work and we in aviation all appreciate it."-Santa Barbara Aero Club, Earle Ovington, Commodore, Santa Barbara, California, November 24, 1926

".....It is quite astonishing how fast and how accurately your published reports meet the needs of the field."- E. A. Briner, Consulting Engineer, East Orange, N.J.

".... I received the Reports almost immediately, for which favor I would like to thank you very much. They contain such precious information that I wonder how I ever got along without them until now."- G. M. Bellanca, Aeronautical Engineer, Omaha, Nebraska, December 22, 1923




"...I wish to commend the very interesting work which you are doing, and to have you know that we sincerely appreciate the big part which you are playing in original research work which contributes so much to the development of aeronautics." - The Pratt and Whitney Aircraft Co., F. B. Rentschler, President, Hartford, Connecticut, December 19, 1925

"....These reports are helpful to us beyond explanation . Permit me through you to extend my appreciation for the great assistance in industry the Committee has been to us, and the gratitude of my organization for each and every one associated with the Committee." - Charles E. Lay, Commercial Aeronautical Engineering, Cincinnati, Ohio, January 12, 1925

[669] "...I have for the past year been a project engineer with the Lockheed Aircraft Corporation. The technical data I have received from the Committee have been invaluable to me . . . . the publications of the Committee constitute by far the greatest source of research data in this country, and no engineer who wishes to keep abreast of developments can afford to be without them." - Richard W. Palmer, Pasadena, California, February 3, 1930

"....the conference was the most impressive and instructive one of this kind that I have ever had the privilege of attending, and you will be gratified to know that in our research work we have already been able to derive very definite advantage and assistance from the publications and work of your Committee. "- Grover Loening, May 16, 1929

"I was very glad to receive the data on N.A.C.A. 2412 forwarded with your letter of the 7th. It came to hand at just the right moment; in fact, I was on the point of writing you a letter and asking you if I might not be supplied with this information. Another good example of the very efficient service rendered by the Committee." - Chance Vought Corporation, East Hartford, Connecticut, January 14, 1932

"....In prosecuting this work I feel that the N.A.C.A. is making the biggest contribution that is possible in aviation at the present time, and the fact that the results of your work are made immediately available to the industry will do much to hasten the progress in aviation."-Packard Motor Car Company, J. G. Vincent, Vice President of Engineering, December 20, 1927

Your Committee is to be "...congratulated on the marvelous work done during the past year. I cannot help but feel that the Committee's new equipment and results achieved are among the outstanding achievements of the year in aeronautics..." - Consolidated Aircraft Corporation, January 29, 1932

"...Your work is of great assistance to us and is highly appreciated." - Pan American Airways, Inc., New York City, March 3, 1930

"...We wish to take this opportunity of expressing to you our appreciation of the many courtesies extended to us by your Committee in the past. Your Reports and bulletins have been of the greatest assistance to us." - Amphibions, Incorporated, Garden City, N.Y., October 16, 1931

"...Many thanks to you for the copy of Technical Note No. 219, 'The Comparison of Well-Known and New Wing Sections Tested in the Variable Density Wind Tunnel,' which I have just received. It is a very, very fine report and I want to congratulate you upon the way it is presented and the abundance of information contained therein. It is just another example of the good work that is carried on by the N.A.C.A. and we are getting so accustomed to the thoroughness of your reports that, naturally, we expect them all to be alike." - A. V. Verville, Buhl-Verville Aircraft Co., Detroit, Michigan, August 20, 1925

"...I never before appreciated the great importance to aviation that the National Advisory Committee really is; the wonderful work that they are doing and the true interest that is shown in aviation by the results of their efforts...the value to aviation of the research work which is represented in those volumes is immeasurable." - Skylark Airplane Co., Inc., Detroit, Michigan, May 5, 1927


28. "Economic Value of the National Advisory Committee for Aeronautics," Jan. 1933.


[The NACA maintained that its appropriations from Congress were cost-effective because its research resulted in savings to the armed services and to the American aviation industry. Nowhere was that argument more explicit than in this document, [670] prepared when a move was afoot to transfer the NACA to the Department of Commerce.

NACA research unquestionably contributed to more efficient flight in the United States, but that fact does not guarantee the logic or the accuracy of the computations presented here. (The Committee was careful to label them possible savings.)




The conduct of fundamental scientific research in aeronautics by the National Advisory Committee for Aeronautics in one central Government laboratory, to meet the needs of all branches of aviation, is not a Governmental luxury that can be sacrificed. It is a necessity, vital for national defense because of its fundamental influence in enabling the Army and the Navy to keep abreast of other nations in the development of aircraft.

No money estimate can be placed on the immeasurable value of superior perform-ance of aircraft in warfare, for aerial supremacy is quite likely to be ultimately decisive of a war; nor can a money estimate be placed on the indeterminable savings in life and property due to improved safety in the operation of both military and civil aircraft. The performance, efficiency and safety of aircraft of all types have been materially improved as a direct result of researches conducted by this Committee. The value in dollars and cents of improved efficiency in aircraft, however, can be estimated. Six researches completed within the last few years have been selected, which show that, when the results are applied to airplanes equal in number to those in use during the fiscal year 1932, savings in money alone will be made possible in excess annually of the total appropriations for the Committee for the eighteen years of its existence.




In arriving at the estimated possible savings through the use of the N.A.C.A cowling on all types of airplanes, the following factors were considered for each type of airplane in use in the United States for military, naval, and commercial purposes during the fiscal year ended June 30, 1932:


1. Actual hours flown; reduction in drag through use of cowling (at cruising speed); reduction in horsepower required through use of cowling for same cruising speed; reduction in initial cost of engine of less horsepower required; reduction in cost of airplane maintenance and operation resulting from saving in weight, including: Saving on depreciation; saving in insurance and interest charges on commercial airplanes and engines; saving on fuel and oil; and saving in maintenance costs of airplane and engine.
2. From the gross saving thus computed for each airplane in service there was deducted the cost of installation and maintenance of the N.A.C.A. cowling.
3. The remainder is the net saving per year for each airplane of a given type.

These factors applied to the airplanes in use in the United States by the Army, by the Navy, and by commercial operators, show estimated possible savings per year as follows:





Total, military savings


Commercial savings


Total annual savings from use of N.A.C.A cowling





In arriving at the estimated possible savings through the use of the N.A.C.A. engine-propeller position in the wings of all types of multi-engine airplanes, the following factors were considered for each type of airplane in use in the United States for military, naval, and commercial purposes during the fiscal year ended June 30, 1932:


1. Actual hours flown.
2. Improvement in net efficiency due to use of N.A.C.A. engine propeller location.
3. Reduction in horsepower required at cruising speed.
4. Reduction in initial cost of engines of less horsepower required.
5. Reduction in cost of airplane maintenance and operation resulting from saving in weight, including:
(a) Saving on depreciation.
(b) Saving in insurance and interest charges on commercial airplanes and engines.
(c) Saving on fuel and oil.
(d) Saving in maintenance costs of airplane and engine.

These factors applied to the multi-engine airplanes in use in the United States by the Army, the Navy, and commercial operators, show estimated possible savings per year as follows:





Total military savings


Commercial savings


Total annual savings through use of N.A.C.A. engine-propeller position in multi-engine airplanes





The conventional type of gasoline engine is a four-stroke-cycle engine: that is to say, each piston makes two up-strokes and two down-strokes in delivering one power stroke. In the two-stroke-cycle engine, each down-stroke of a piston is a power stroke. Certain physical difficulties have existed, however, to delay the development of the two-stroke-cycle engine for general use in aircraft.

The N.A.C.A. has conducted researches for several years to solve these difficulties. It has made definite progress on the fundamental difficulties involved, as, for example, in the scavenging of burned gases from the cylinders and in the injection of fuel under pressure. The progress thus far made in the Committee's laboratory indicates that a two-stroke-cycle engine having compression ignition and fuel injection can now be built at an average weight of 1.4 pounds per horsepower as compared with the present average weight of 2 pounds per horsepower.


Total horsepower developed in Army, Navy, and commercial airplanes (hp)


At average of 2 pounds per horsepower for four-stroke-cycle engine (pounds)


At average of 1.4 pounds per horsepower for two-stroke-cycle engine (pounds)


Weight saved using two-stroke-cycle engine (pounds)


Multiplied by cost per year per pound of weight flown


Annual possible saving





By scientific investigations conducted by the National Advisory Committee for Aeronautics to determine the distribution of air loads imposed on airplane structures in flight, it is now possible so to design airplane wings as to give requisite strength with minimum weight.

For convenience in evaluating the saving thus made possible in the annual operating costs (disregarding savings in production costs), the single-engine commercial airplanes have been estimated at 5000 pounds each and multi-engine commercial airplanes at 15000 pounds each.

5,000-pound airplanes, 453 at 270 pounds saved per airplane (pounds)


15,000-pound airplanes, 199 at 610 pounds saved per airplane (pounds)


Gross weight saved on commercial airplanes operated in 1932 (pounds)


Annual saving at $4.02 per pound per annum





Considering a typical cabin monoplane with N.A.C.A. 2415 wing installed in lieu of the previous conventional wing, there would be, at a cruising speed of 120 miles per hour, a reduction in total drag including wing and control surfaces of 17.28 pounds per airplane.

Cost per pound of drag per hour of flight

$.03 1/2

Saving per hour of flight at 17.28 pounds drag saved per airplane


Possible savings per annum at 60 per hour of flight per airplane, based on number of airplanes used during 1932:





Total savings to Government


Commercial savings


Total savings per annum





The National Advisory Committee for Aeronautics through researches conducted at its laboratories at Langley Field, Virginia, has made possible an 18 percent increase in power of aircraft engines by using large valve overlap combined with fuel injection principle. Based on the aircraft engines in use in the United States during the fiscal year 1932, this principle makes possible an annual economic saving of $598,742, arrived at as follows:

Power saved (percent)


Total brake horsepower hours developed during year on aircraft engines of all types


Assuming liberal estimate of 1,000 hours' operation per year, the horse-power developed was (hp)


18% of above = horsepower saved (hp)


Equivalent weight saved at rate of 2 pounds per horsepower (lb)


Economic value of weight saved at $4.02 per pound per annum



[673] 29. The Brookings Institution, "Memorandum on Report No. 12 on Senate Select Committee Making Recommendations Relative to National Advisory Committee for Aeronautics," 8 Nov. 1937.


[In 1937 the Brookings Institution analyzed the organization of the federal government at the request of the Senate Select Committee to Investigate Executive Agencies of Government. The goal was to suggest economics that could be effected through the elimination of duplication, a constant concern in Congress. Report No. 12 of the Institution recommended that the NACA be transferred to the Department of Commerce. This memorandum summarizes that report. Note that the efficiency and effectiveness of the NACA were never even brought into question, let alone studied; the recommendation turned entirely on general principles of organization. Congress failed to act on this recommendation, but the issues raised here remained a constant threat to the NACA's autonomy and independence.]

The staff of the Institute for Government Research has reviewed the analysis and recommendations . . . contained in the section on air transportation and finds no basis for modifying the conclusions reached relative to the recommended transfer to the proposed Department of Transportation (the Transportation Section of the Department of Commerce) of the functions now performed by the National Advisory Committee for Aeronautics. The reasons for this conclusion are briefly set forth as follows:

The chief purpose of the reorganization study was to discover at what points and by what methods the functioning of the Executive branch of the government could be improved by the elimination of overlappings, duplications, and conflicts in authority and operation.

In the case of the National Advisory Committee for Aeronautics our analysis revealed a clear-cut case of duplication in the research work which this agency and the Bureau of Air Commerce are now authorized to carry on. Our recommendation that the work now done by the N.A.C.A. ". . . should be fitted into the general research program developed by the Department of Transportation in carrying out its airtransport promotional work..." was designed to eliminate this duplication. We made no analysis of the detailed functioning of the N.A.C.A., nor did we express any judgment relative to the quality of its work. The validity of our recommendation does not depend upon such analysis, for we did not suggest discontinuance of the function- merely its transfer from one agency to another.

Moreover, we discovered nothing in the general character of the work done by the NACA which would require that it be divorced from effective executive control in order to function properly. Its work is not in any way judicial or legislative in character. It can properly be performed (as is the case with similar basic research work carried on by the experimental stations of the Bureau of Public Roads) within the framework of the appropriate executive department.

Our recommendation was, therefore, based on the following considerations:

1. Two federal agencies, the Bureau of Air Commerce, and the National Advisory Committee for Aeronautics, are now authorized and instructed to carry on basic research work in the field of aeronautics.
2. One of these agencies, the Bureau of Air Commerce, is in addition charged with primary responsibility for the promotion and regulation of air commerce in furtherance of the declared policy of Congress to build and maintain a safe, adequate, economical, and efficient air transport system, designed
(a) To meet the reasonable needs of the American people for air transportation;
(b) To supply reasonable air mail service;
[674] (c) To make available an air craft manufacturing industry capable of expansion in time of national emergency to meet the military needs of the country; and
(d) To insure the expeditious development of miscellaneous flying.
3. Basic research in the fundamental problems of flying, the physical characteristics of materials and operating equipment, etc., must be carried out by the Bureau of Air Commerce in order to discharge its statutory responsibilities.
4. The work now done by the NACA is neither judicial nor legislative in character and consequently does not require independent organizational status.
5. Its present status is explained largely by historical factors.

All of those points might have been elaborated in the transportation report. Such elaboration applied consistently to analysis of the 21 major federal agencies engaged in activities affecting transportation obviously would have extended unduly this section of the report. We did, however, indicate briefly:

1. That between 1915 and 1926 the federal government's activities in the field of aeronautics were based almost exclusively upon military considerations
2. That the NACA was created in 1915 as a part of this limited program
3. That beginning with the Air Commerce Act of 1926 congressional policy has progressively shifted in emphasis from the military to the economic aspects of air transportation
4. That the work of the NACA has not been limited to its original major purpose- basic research in aeronautics designed to serve military purposes- but has followed the trends in the development of air transportation generally. This observation is supported by the committee's stated objectives of its research work:
"...(1) to coordinate the research needs of aviation, civil and military; (2) to define the problem to be investigated; (3) to allocate the problems to prevent overlapping and duplication; (4) to anticipate research needs; (5) to organize and conduct at one central governmental service laboratory (Langley Field) scientific research on the more fundamental problems of flight, and especially those problems requested by the Army, Navy, and the Bureau of Air Commerce; (6) to disseminate resulting new knowledge; (7) to pass upon technical merits of aeronautical inventions; and (8) to conduct specific investigations for and at the expense of the aircraft industry when adequate facilities are not elsewhere available.".
5. Under the terms of the Air Commerce Act of 1926 and amendments the Bureau of Air Commerce is instructed among other things to " ... 'study the possibilities for development of air commerce and the aeronautical industry and trade in the United States, and to collect and disseminate information relative thereto' . . . 'to advise with the Bureau of Standards and other agencies in the executive branch of the Government in carrying forward such research and development work as tends to create improved air navigation facilities.'..."

Such research work is essential to the formulation of technical rules regarding equipment, flying, landing, the determination of responsibility for air accidents, etc., with which the Bureau of Air Commerce is charged...

Consideration has been given to the question whether the fact that the N.A.C.A. as originally set up was concerned largely with questions of national defense does not indicate that it should be preserved as a separate agency independent of any department. We do not think this is the case for the following reasons: (1) As already indicated, the work of the N.A.C.A. has been steadily broadened to include other than military aspects of the problem; and (2) the Bureau of Air Commerce has been established to deal with problems of national defense as well as air transportation generally. The logic of the situation clearly calls for the consolidation of these agencies in the interests of economy.

[675] Assuming the accuracy of our analysis of the functions of the National Advisory Committee for Aeronautics and since we failed to discover any compelling reason why its present work could not be effectively performed by the Bureau of Air Commerce (or whatever agency might be designated to administer the general air transportation policy of the government) our recommended transfer of the N.A.C.A. to the Bureau is essential to the preservation of the internal consistency of the report as a whole. The Bureau of Public Roads, for example, has for years carried on basic research work in the strength of materials, subsoil conditions, stresses and strains upon materials, etc., as an integral part of its administration of the federal aid acts. These research activities are equally as fundamental to the proper administration of the federal aid acts as are analogous research activities to the effective administration of air transport legislation. Both have their military implications. If convincing reasons can be found for the severance of fundamental research policy from the administration of general air transport, we would have been compelled for the sake of consistency to recommend transfer of the fundamental highway research now carried on by the Bureau of Public Roads, to an independent organization. We discovered no justification for such a recommendation, nor did we find any basically distinguishing features which would require that one phase of the research function should be carried on by a department, and the other by a semi-official organization, financed with federal funds, but divorced from any effective control of the government unit charged by Congress with responsibility for administration of the federal government's air navigation program.


30. Westover Committee Report, 19 Aug. 1938.

[Shortly before his death, Maj. Gen. Oscar Westover joined two other members of the NACA in an attempt to formulate a policy to govern the NACA in the event of war. Their report laid down the principles endorsed by President Roosevelt the following year and implemented in World War II. Although this policy solved many problems for the NACA, it left the deferring of NACA personnel from military service to be worked out slowly and painfully during the war.]


Subject: Relation of the National Advisory Committee for Aeronautics to National Defense in Time of War.

To: Chairman, National Advisory Committee for Aeronautics.

1. The committee appointed for the purpose of considering the study covering the relation of the National Advisory Committee for Aeronautics to National Defense in Time of War . . . finds that the questions contained therein can be resolved into the following elements:

a. What is the present status of the NACA in regard to National Defense?

b. (1) What should be the status and relation of the NACA to National Defense in a national emergency? (2) Where does it fit into the scheme for National Defense?

c. What should be the status of the personnel of the NACA during a national emergency?

d. How should the NACA obtain additional personnel, if needed for expansion, in time of an emergency?

2. With reference to the questions listed in Paragraph 1, above, the following remarks are made:

Q. a. What is the present status of the NACA in regard to National Defense?

A. Peace Status. The NACA is a Federal agency, with a mission prescribed by law. It performs essential work for the Army, the Navy, other Federal agencies, and for the Aeronautical Industry.

[676] Q. b. What should be the status and relation of the NACA to National Defense in a national emergency? (2) Where does it fit into the scheme for National Defense?

A. War Status.

(1) The status of the NACA in a national emergency has not been fixed.

The services of the NACA are deemed to be essential to National Defense for the successful prosecution of a war.

(2) The NACA can properly submit recommendations to higher authority as to its proper place in the scheme for National Defense. These recommendations could be that-

(a) The NACA continue to function as a separate entity, the same as it does in peace. In this connection, a mobilization plan should be prepared and submitted to the President for approval. Such action would place the NACA in the category of an Independent Establishment, Board, or Commission (; also, on a parity with the Armed Forces in case of an emergency, rather than as an integral part thereof. The degree of coordination and cooperation between the NACA and the agencies which would have paramount need for the services of the NACA should be given careful consideration. The Armed Forces will, undoubtedly, desire a more definite status for the NACA than one based upon coordination and co-operation.

(b) The NACA become an adjunct of The Aeronautical Board. The Aeronau-tical Board is a continuing Joint Board . . . . Since the NACA upon the declaration of a national emergency would, undoubtedly, confine its activities to aeronautical matters and since such aeronautical matters jointly concern the War and Navy Departments and are handled by the Aeronautical Board, the services and resources of the NACA could well be utilized by this joint Board. Such a position would make the NACA a part of the Armed Forces, and, on one hand, would permit direct collaboration and/or action between the NACA and the Chief of the Air Corps and the Secretary of War; on the other hand, the Chief of the Bureau of Aeronautics and the Secretary of the Navy. It is realized that such action would place the NACA, for the period of the emergency, in a more subordinate position than that which it now enjoys; however, in the interests of National Defense, this is believed to be a logical plan.

An effort to definitely place the NACA in such a position in the scheme for National Defense is shown in . . . [a] proposed Mobilization Plan for The Aeronautical Board. That portion of this Mobilization Plan which pertains to The Aeronautical Board proper was drawn up by a subcommittee of that Board and has not, as yet, received the approval of The Aeronautical Board. It is realized that the submission of Section 3 of this plan to The Aeronautical Board would be only as a recommendation as to the line of action which would be acceptable to the NACA and that the final Mobilization Plan would be drawn up by The Aeronautical Board and submitted to the NACA for its comment, or approval, prior to submission thereof to higher authority.

Q. c. What should be the status of the personnel of the NACA during a national emergency?

A. The committee at present consists of military and civilian personnel. No cogent reasons can be advanced which would require a change to a military status for such members in time of an emergency. It is believed that no advantage would be conferred, by a military status, upon the personnel employed by the NACA, either in its Washington offices or in the Langley Memorial Aeronautical Laboratory at Langley Field, Virginia. A civilian status for such personnel will, undoubtedly, meet with military approval as the granting of military rank to personnel [677] engaged upon quasi-military work as was done during the World War is not now believed to be desirable.

Q d. How should the NACA obtain additional personnel, if needed for expansion, in time of an emergency?

A. The answer to this question is dependent upon the decision adopted by the Committee as to where the NACA should be placed in the scheme for National Defense; for instance-

(1) If the NACA is to remain a separate entity, then it would include in its Mobilization Plan suitable paragraphs on the subject of personnel.

(2) If the NACA is to become an essential adjunct of The Aeronautical Board, then the Aeronautical Board in its Mobilization Plan should provide for the necessary personnel to properly carry on the activities of the NACA.

3. In connection with this study, the question of "blanket deferment" for NACA personnel was raised, and it is believed that no time or thought should be given to this question as it is not considered to be possible of attainment- the American Legion is definitely opposed to the granting of "blanket deferment" to any industry or class of personnel. The solution recommended is as follows:

a. The case of each individual employee must be considered on merit, when war is imminent, due regard being given to the qualifications, position held, and the recommendations of the management (NACA) as to the need for the services of the individual concerned.

b. The attitude of the War Department on this matter in the past is believed to be essentially as follows:

(1) No attempt has been made to place restrictions on appointments of Reservists from either allocated or unallocated facilities.

(2) It has not been the policy to deny an Army Reserve' commission to an applicant merely because he may be employed by an allocated facility. It is true that the effect on industry by sudden withdrawal for war service of employees who hold Reserve commissions has caused some concern, but, because of the many considerations involved, it has not been thought practicable to attempt to apply a restriction to Army Reserve officers based on whether they could or could not be spared by their employers without grave detriment to essential war production. A principal hindrance to such a classification is the fact that a Reserve officer's status and occupation in civil life may change frequently. Each case must be considered on its merits, when war is imminent, due regard being given to the qualifications, position held, and the recommendations of the management as to the need for the services of the individual concerned.

(3) It must be realized that certain deferments will have to be made in order to be able to supply munitions to the fighting forces and avoid the necessity for wholesale exemptions. To the end that this may be accomplished the matter is now under study and it is believed possible to work out detailed plans to apply in every instance that will serve to minimize interference with essential war production and at the same time not deny to the Armed Forces the use of such men as may be particularly fitted and necessary for the military and naval services.

4. The committee recommends that:

a. The NACA seek a place in the scheme for National Defense as an essential adjunct of The Aeronautical Board for the duration of a national emergency only.

b. The personnel employed by the NACA continue on a civilian status after the outbreak of an emergency.

c. The question of "blanket deferment" for such personnel not be raised as a satisfactory solution can be obtained by other means.

d. No restrictions or objections be made to personnel of the NACA accepting commissions with the military forces in time of peace; however, due notice to be [678] given the military forces that the NACA is an "Essential Industry" and requests for "individual deferments" must be expected by the military forces.






Major General, Air Corps, Chief of the Air Corps, Chairman.

(s) A. B. COOK,

Rear Admiral, U.S. Navy, Chief Bureau of Aeronautics, Member.

(s) W. R. GREGG,

Chief of Weather Bureau, Department of Agriculture, Member.


31. H. H. Arnold to George W. Lewis, 5 Jan. 1939, enclosing "Discussion of a Proposal to Establish an Aeronautical Laboratory for Applied Research.


[Late in 1938, Clark B. Millikan of the California Institute of Technology suggested to H. H. Arnold, Chief of the Army Air Corps, that the government fund an applied aeronautical research laboratory at Caltech as a national defense measure. In his formal proposal he chose to identify two kinds of aeronautical research, basic and applied. When Arnold forwarded the proposal to the NACA for comment, he added a third kind, production research. Commenting on this correspondence, John Victory proposed still another formulation of the division of research (see document 32). Between the lines of Millikan's proposal can be seen implied criticisms of the NACA, an attempt by Caltech to do on the west coast what the NACA was doing at Langley, and a catalyst for the NACA to build its own laboratory in California.]



Dear Dr. Lewis:

During a recent trip to the West Coast, Dr. Millikan brought up the subject of Government sponsorship of aeronautical research activities and its relationship to the National Defense. While the enclosed proposal is pertinent to the procurement of military aircraft, it is a matter which properly falls directly within the authority and responsibility of the N.A.C.A.

It is the opinion of the undersigned that aeronautical research activities should be divided as follows:

(1) Basic Research. The N.A.C.A. to be directly responsible for the correlation and coordination of all basic research conducted by Governmental establishments. To coordinate research and development activities in the fields of Applied Research and Production Research, which in so many instances will suggest new problems for basic research.

(2) Applied Research. The Army and Navy to be directly responsible for the coordination and immediate application of new aerodynamic theories, principles, and discoveries to the particular problems of military aircraft. This involves close cooperation between Wright Field, the Naval Aircraft Factory, and engineering staffs of the aircraft factories.

(3) Production Research. The engineering staffs of the various aircraft factories to be responsible for the conduct of the various aerodynamic tests and experimentation that is connected with the successful completion and production of military aircraft. This Production Research to be conducted in the facilities available at Universities or other private or civilian institutions in the vicinity of the manufacturer concerned.

Plans for new facilities at Wright Field will be coordinated with the N.A.C.A. with a view of making it possible to eliminate Basic Research from the Wright Field aerodynamic experimental programs.

Since there is no definite line of demarcation between the characteristics of a Basic Research tunnel and one primarily designed for Applied Research, there is [679] bound to be some overlapping between the aerodynamic research facilities of the N.A.C.A., Wright Field, the Naval Aircraft Factory, and Educational Institutions, which indicates quite definitely the necessity for coordination of all activities by the N.A.C.A.

With the above in mind and with the idea that your organization should be the coordinating agency, the enclosed project from the California Institute of Technology is forwarded for such action as is necessary. In the opinion of the undersigned there is a need for additional Production Research facilities on the West Coast for the use of the aircraft industry. These additional facilities are in excess of any which the N.A.C.A. may find necessary to construct to carry on its own functions.

Sincerely yours,






Major General, Air Corps, Chief of the Air Corps.





The great expansion in the United States Air Services, which is now under discussion as a national defense measure, will require a corresponding enlargement in the country's aeronautical research facilities. Research in aeronautics can be divided into two categories, which may be described by the adjectives "basic" and "applied." The former is concerned with fundamental problems not associated with any specific aircraft design, while the latter deals with questions arising in the development and design of a particular machine. The two categories are far from unrelated and must be developed together in order that research activities may have anything like their maximum possible efficiency. The following discussion treats certain aspects of the question of applied research in aerodynamics, but the latter's connection with the basic field will often appear.

The fundamental tool for experimental applied research in aerodynamics is the wind tunnel, and it seems very certain that the wind tunnel's importance in this connection will increase rather than diminish in the future. It, therefore, appears that an immediate consequence of any considerable aeronautical expansion will be the necessity for an increase in the wind tunnel facilities available for applied research.


Characteristics of an Applied Research Wind Tunnel

There are certain characteristics which wind-tunnel testing in connection with applied research should possess, but which may not be essential to basic research investigations.

a) The tests must be rapidly made and the results be immediately available.

b) Changes and modifications to the models must be relatively simple to make.

c) It must be possible to decide on modifications and further tests in the light of data just obtained, and without delaying the testing.

d) The Reynolds number must be large enough so that critical points do not occur between the test and full-scale values.

e) The models must be large enough to permit the accurate reproduction of important details, but small enough so that their expense is not excessive. .

It appears that a new wind tunnel, designed primarily for applied research in connection with airplane designers and manufacturers, should have approximately the following characteristics in order to make the most effective possible contribution to airplane design: It should be a closed-return type with a working section about 12 feet in diameter, with an operating speed of about 400 mph at normal density, and should be capable of being partially evacuated so as to permit the attainment of maximum speeds of the order of 600 mph. It must also have the features listed under a) to e) at the beginning of this section.


[680] Desirability of Some Decentralization of Applied Research in Aerodynamics

There are many factors which lead to the conclusion that a certain amount of decentralization is desirable in connection with research work of the type in question. Requirements a), b), and c) of the previous section indicate the importance of close cooperation and contact between a manufacturer whose design is undergoing tests and the testing personnel of the wind-tunnel agency. Such contact is enormously facilitated if the factory and laboratory are reasonably near one another. Since the aircraft industry in the United States, to a very large extent, located in several well-defined but widely separated regions, a number of applied research centers is immediately indicated. The flexibility in testing procedure, which is essential to satisfactory cooperation in industrial wind-tunnel testing, is also much easier to maintain in a relatively small laboratory than in a great central research establishment.

In any such expansion as is currently being considered, the central governmental research organizations, such as the N.A.C.A. and the Army station at Wright Field, would, of course, be very largely increased in size. There are, however, limits to the amount of expansion which can efficiently be carried out with any organization in a short time. Above these limits such an expansion is most effectively accomplished through subdivision and the development of separate units.

Such a subdivision might even be carried to the extreme in which each factory maintained its own laboratory and wind tunnel in which all of its individual research work was done. This, however, would be highly undesirable. In the first place, a laboratory capable of dealing adequately with most of the designers' problems would involve far too much capital investment for any one company. Furthermore, a single company could not make enough use of the required elaborate equipment to justify its cost. There are many cooperative investigations which fall into the category of basic research, but which are of importance to several companies at the same time. Such investigations can be carried out much more satisfactorily by an independent than by a company laboratory.

The combination of basic and applied research, which can be effectively handled by an independent research organization working in close cooperation with manufacturers' engineers, furnishes a powerful argument in favor of this type of laboratory. It very frequently happens that interesting and important basic research problems are suggested during a more or less routine industrial test. Such problems often do not come to the attention of pure research workers, and they can almost never be pursued in a company laboratory. They cars, however, be readily incorporated into the basic research program which an independent research laboratory would normally be engaged upon as a background for its applied research activities.

Coordination is, of course, a very important element in the efficient progress of research. However, it has often been demonstrated that coordination can be very satisfactorily attained between several laboratories, even though they are at large distances from one another. On the other hand, very great advantages are derived from the stimulus of friendly competition between such laboratories. The greatest advances, not only in experimental technique but also in the development of new ideas, very frequently occur when several groups are attacking the same type of problem more or less independently.

In view of the above remarks, it is interesting to note the methods adopted by the Germans in their recent remarkable expansion in aeronautical research. The central government agency, the D.V.L.,* was greatly enlarged, and this indeed was the most striking feature of their program. However, another extremely important and carefully worked out element was the setting up of five elaborately equipped research establishments [681] at the leading centers of higher technical education throughout the country. Each of these establishments, under the direction of one of the local professors, functions as an independent research laboratory, although the activities of all are correlated through the Air Ministry. A study of the recent issues of the Air Ministry's publications Luftfahrtforschung, shows that this type of organization has already proved remarkably fruitful, as indicated by only the published output from these independent laboratories.


Desirability of Locating an Applied Research Laboratory at the California Institute of Technology

At the present time, approximately 50% of all the airplane building of the country is carried out in a relatively small region in Southern California. Practically all of the wind-tunnel testing associated with the development of this great industry has been done in the ten-foot wind tunnel of the Guggenheim Aeronautics Laboratory at the California Institute of Technology (hereafter referred to as GALCIT). When this laboratory was constructed in 1928, it was planned that the time of the wind tunnel should be about equally divided between basic research and applied research or industrial testing. However, the demands of the industry have been so overwhelming that during the past several years it has been necessary to operate the wind tunnel 15 to 16 hours per day with two complete shifts of workers, and only 16% of its time has been available for basic research problems. It is clear that the existing facilities are sorely overtaxed and that any further expansion of the industry will make an enlarge-ment of research equipment and staff essential.

A brief resumé of the applied research activities of the wind tunnel over the eight-year period of its operation to date will indicate something of the scope of its work. A total of 138 reports has been prepared, covering separate investigations for manufacturers on 50 completely distinct models. Many of these models were tested several times in modified forms, the later modifications being suggested by the results of the previous wind-tunnel tests. Of these reports approximately 60% dealt with military or naval models, while the remaining 40% were concerned with commercial aircraft. The investigations were, conducted for eighteen different companies, five major firms accounting for a very large majority of all the tests. As mentioned above, the tunnel has been operated with two shifts of workers for the past several years, during which period its testing facilities have usually been reserved for two to three months in advance. In addition to this industrial testing, a large number of basic researches has been carried on, particularly in the earlier years before the wind-tunnel congestion became so severe.

The organization which has been developed as a result of the experience gained in this work is a somewhat unusual one. The industrial testing is under the direction of one of the members of the California Institute staff, whose applied research activities are considered as separate from his academic ones. He is assisted by two other members of the academic staff who are part-time members of the wind-tunnel group. Three permanent technical assistants are also included in the organization. A considerable proportion of the actual running of the tunnel is done by postgraduate aeronautical students of American citizenship. All members of this group are pledged to secrecy regarding industrial testing and are required to have no affiliations with any aircraft company. Since 1930 the California Institute has awarded 141 degrees for postgraduate work in aeronautics. A considerable proportion of all the United States citizens represented in this list has worked for one or more years on the wind-tunnel staff. It is felt that the training thus received has been extremely valuable to these men in their later careers as aeronautical engineers. In case of a large expansion in aeronautics, one of the vital problems will be the adequate training of a sufficient number of engineers, and such an arrangement as that just outlined should be of considerable assistance in supplying this need.

[682] Summarizing the above discussion, it would appear that a modern applied research laboratory located at the California Institute of Technology could be of great service in view of the following points:

1) The great concentration of aeronautical industry in Southern California, far removed from the government research centers in the east.

2) The proven demand for such a laboratory, for which the existing facilities are very inadequate under present conditions. Hence even a moderate expansion of the local industry would make a material enlargement in the applied research facilities essential.

3) The very considerable experience of the GALCIT wind-tunnel staff in the field of applied research, and the close connections already developed between it and the airplane industry.

4) The possibility of effectively combining industrial testing with basic research, which would be afforded by the present equipment and staff of the GALCIT.

5) The procedure already developed at the GALCIT for giving advanced American students valuable experience through industrial testing, in their training as aeronautical engineers.


Specific Proposal for an Applied Research Laboratory

In the light of the preceding discussion, the following proposal is suggested as solving one of the problems raised by any considerable expansion in the United States air force:

1) To establish, as a national defense measure, an aerodynamical applied research laboratory at the California Institute of Technology, under the direction of one or more of the departments of the United States government, such as the War Department, the Navy Department, and the Civil Aeronautics Authority.

2) The primary purpose of this laboratory would be to carry out tests for manufacturers engaged in producing airplanes for the government.

3) The chief element in the laboratory would be a very modern wind tunnel, whose characteristics would be such as to permit the investigation of the major aerodynamic problems which can be expected to arise in the near future.

4) The laboratory would work in close cooperation with the N.A.C.A., Wright Field, and the other governmental research agencies concerned with aeronautics.

5) The details of organization and administration need not be discussed in this preliminary memorandum. It should, however, be pointed out that a some-what similar cooperative arrangement between the California Institute and the U.S. Department of Agriculture has been carried on very successfully during the past two years in connection with the latter's "Cooperative Laboratory, Soil Conservation Service, California Institute of Technology."

The approximate characteristics of the wind tunnel which is suggested as satisfying the anticipated requirements are as follows:


Type- Single-return, closed working section, capable of compression up to 4 atmospheres or evacuation to 1/4 atmosphere, circular cross section throughout.

Dimensions- Working section diameter = 12 ft.; Working section length = 18 ft.; Contraction ratio = 4; Overall length = 135 ft.; Fan diameter = 18 ft.

Construction- Welded 1/2-in. steel plate, water cooling on surface and vanes.

Power- Two 4000 h.p. A.C. motors driving oppositely rotating propeller-type fans with adjustable pitch blades. The motors are designed for short-period operation at 50% overload.

Approximate Performance (with motors operating at 50% overload of their rated power): Maximum speed at 1/4 atmosphere pressure =630 m.p.h.

Maximum speed at 1 atmosphere pressure = 415 m.p.h.

[683] Maximum speed at 4 atmosphere pressure = 260 mph.

Maximum Reynolds number at 4 atmospheres pressure with aspect ratio 6 model and moderate tunnel wall corrections = 16.5 X 106.

A preliminary analysis leads to the following estimate of the probable costs of the wind tunnel, the necessary associated equipment, and the building required to house them:


Tunnel structure, electric drive, cooling system


Balance systems, shop facilities, associated research equipment


Building (heating, ventilating, furniture)





32. Memorandum, John F. Victory to Dr. Lewis, "General Arnold s letter of January 5, 1939, re basic research, applied research, and production research, " 9 Jan. 1939.


The NACA always tried to define its research in such a way as to render it unique in the United States, duplicating no other agency or institution. In this rebuttal to document 31, John Victory displays some of the defensiveness and sophistry that crept into these claims. Aeronautical research is simply too complicated to be compartmentalized as neatly as NACA management might have wished.]


1. The National Advisory Committee for Aeronautics conducts scientific research in aeronautics, including basic research and applied research. The law provides that it shall be the duty of the Committee "to supervise and direct the scientific study of the problems of flight with a view to their practical solution, and to determine the problems which should be experimentally attacked, and to discuss their solution and their application to practical questions." The law also authorizes the Committee to "direct and conduct research and experiment in aeronautics."

2. It is the policy of this administration, as it has been of previous administrations, to avoid and prevent unnecessary overlapping and duplication in the Government activities. In the field of aeronautical research this responsibility devolves upon the Committee.

3. An analysis of the activities of the Committee at its Langley Field laboratories indicates that the major portion- approximately 70 percent- of its work has been scientific investigations undertaken at the request of either the Army or the Navy to meet present needs. Aside from the inherent and insuperable difficulty of drawing a clear line of distinction between basic research and applied research, both of which are now conducted and coordinated by the Committee without overlapping or duplication, it appears quite clear that if the Committee were to be limited to so-called basic research, so much would remain undone that is necessary to meet the needs of military, naval, and commercial aviation, that there would inevitably ensue overlapping and duplication by the governmental agencies concerned in the field of so-called applied research- all at the taxpayers' expense.

4. As a substitute for the basis of clarification of functions proposed by General Arnold, the following outline is suggested:

(1) Scientific Laboratory Research. The functions of the N.A.C.A include the supervision, direction, and conduct of scientific laboratory research in aeronautics; [684] the coordination of the research needs of aviation, civil and military, including the problems of the industry, to prevent unnecessary overlapping and duplication; and the coordination and effective stimulation and support of aeronautical research in educational and scientific institutions.
(2) Military Experimental Engineering. The Army and Navy are directly responsible for the immediate application of the results of scientific laboratory research conducted by or under the cognizance of the N.A.C.A., and bring their research needs to the attention of the Committee; the Army and the Navy conduct experimental engineering and development work necessary to meet their needs in connection with the design and development of military and naval aircraft and equipment; the Army and the Navy conduct necessary research in any branch of aeronautics for which the N.A.C.A. has no facilities or inadequate facilities- any such research activities being coordinated through the N.A.C.A. subcommittees so as to increase if possible the value of the results and also to avoid unnecessary overlapping or duplication of effort.
(3) Industrial Experimentation and Development. The engineering staffs of the various aircraft and engine factories are to be encouraged to conduct industrial research, tests, and experiments connected with the successful design and production of aircraft; to have access to the enlarged facilities of the N.A.C.A. for the conduct of any wind-tunnel investigation connected with military or naval aircraft; and to have similar access to the use of the Committee's facilities for the solution of any other problem whenever adequate facilities are not existent or available at the wind tunnels of educational institutions.




33. Jerome C. Hunsaker, "Memorandum on Postwar Research Policy for NACA, "27 July 1944.


[World War II brought a dramatic rise in the size, power, and influence of the American aviation industry, especially of aircraft manufacturers. It also brought into positions of power in the NACA not only industry representatives, but also new officers sympathetic to industry demands for a larger voice in NACA affairs. As NACA Chairman Jerome Hunsaker began considering a postwar research policy for the NACA, he actively sought the opinions of industry representatives. This memorandum summarizes discussions he had during a cross-country trip in mid-1944. Evolution of these comments into a NACA policy can be traced in documents 34 through 36.]


1. The conferences with leaders of the Industry in May and June were frankly exploratory but did, in my opinion, develop general agreement among Industry repre-sentatives on the following points:

(a) NACA should in the postwar period concentrate on fundamental research to advance the aeronautical sciences.

(b) Research reports should eventually be published, but the American industry should be given the results a year or so ahead of foreign competitors.

(c) NACA should not develop specific products or designs, except as necessary to demonstrate a principle or to prove an application.

(d) NACA should investigate the products of industry as requested by government agencies and in this connection do such analysis and development work as may be necessary to overcome defects or to make improvements.

[685] (e) NACA should avoid establishment of facilities for research in those fields where industry is well equipped, i.e., radio, metallurgy, chemistry, fuel technology, etc.


2. On the following points, difference of opinion seemed to prevail:

(a) Whether or not NACA should allow the use of its facilities for the testing (and development) for industry of specific products. The present policy of the NACA concerning the use of its facilities for investigations for the industry of specific products is summarized as follows:

The work desired must relate to aeronautics; must necessarily involve the use of NACA facilities, i.e., adequate facilities not available elsewhere; work is paid for by firm, and results are its exclusive property against remainder of industry, but are available for use of the government.

The larger units of industry may be expected to be in opposition to the smaller plants having access to the use of NACA facilities.

The question is, "In the postwar period should the NACA adhere to this policy?"

(b) In the discussion at Cleveland with the representatives of the industry, there was considerable discussion about the sharing of public funds available for development. The industry inferred that it can use such funds to better advantage than government laboratories in developing specific products and at the same time strengthen their own organizations.

(c) Whether or not the Cleveland laboratory constitutes a potential threat to the engine industry. (The idea here is that private enterprise has already developed very superior engines and fuels and does not need government competition in research, invention, and development.)

3. There is undoubtedly some misconception on the part of representatives of the industry as to aeronautical research versus aeronautical development. The Committee's laboratories in the postwar period would be concerned primarily with aeronautical research. The discussion noted above had to do primarily with engine research. It was recognized in discussion by the members of the Committee that there is a certain overlapping between the fields of research and development.

4. While difference of opinion can be expected, it is fair to state that engineers from industry show no reluctance to use NACA facilities and advice, and their companies express appreciation for NACA help in no uncertain terms. Doubts as to the future role of NACA come from the heads of some of these same companies. My own feeling is that such doubts are based on these factors:

(a) Realization that, with NACA research results and test facilities available to all, the best engineering organizations in the engine field may lose a competitive advantage won by their own enterprise.

(b) Observation that Cleveland seems to be concentrating on the development of one make of liquid-cooled engine to improve its performance.

(c) Observation that NACA is leading jet-propulsion and gas-turbine developments in collaboration with firms previously outside the aeronautical engine field.

(d) Observation that current wartime NACA research activities are largely of a developmental character, which the larger units of the industry can themselves handle when they have a surplus of engineering manpower.

5. It is necessary that the Committee consider its future policy primarily in the light of what the War, Navy, and Commerce Departments plan to do. In particular, our postwar policy should take cognizance of the following changes in the distribution of research and testing facilities since 1940:

(a) Extensive wind-tunnel and engine-testing facilities at Wright Field

(b) Additional Navy facilities at Carderock, Philadelphia, and Patuxent

[686] (c) Wind-tunnel facilities at Curtiss-Wright, Pratt and Whitney, Boeing, California Institute of Technology, North American, and Lockheed

(d) Power-plant facilities at Pratt and Whitney, Wright Aeronautical, Allison, General Electric, Westinghouse, and Allis-Chalmers, and proposed Packard engine-test facilities at Toledo

(e) A strong engineering organization in the C.A.A.,** both in Washington and in the field

(f) Extensive facilities in the fields of aviation physiology, meteorology, metallurgy, radio and armament

6. I believe that when the war pressure from the Army and Navy is relaxed the NACA should revert to its prewar policy of concentrating on fundamental research which it will be free to do to a greater extent than before the war because of the existence of so many new test facilities in the Army, Navy, and industry.

7. In the preparation of estimates for the fiscal year 1946, the Bureau of the Budget has requested four estimates: the first based on continuation of the war in Europe and in the Orient during the fiscal year 1946; the second on the termination of the war in Europe by July 1, 1945 and continuation of the war with Japan; the third on the continuation of the war in Europe and the end of the war with Japan by July 1, 1945; and the fourth on the termination of both wars by July 1, 1945.

In the preparation of these several estimates, plans will be made for curtailment of staff under the contingency that both wars will be over by July 1, 1945, and placing of certain facilities in stand-by condition as the Army and Navy development projects decrease. In preparing these estimates it will be necessary to have a list of Army and Navy research authorizations on which work should continue and a list of research projects of a fundamental character with particular reference to the development of civil aviation, which would be initiated by the NACA upon the termination of the war. Such estimates will include the backlog of fundamental research neglected during the war period.





34. "Notes on discussion at meeting of NA CA, July 27, 1944," 8 Aug. 1944.


[When the NACA Executive Committee discussed Chairman Jerome Hunsaker's memorandum on postwar research policy (document 33) none of the industry members were present. All the government members displayed a familiarity with- and some sympathy for- industry views on government research in aeronautics, especially on the vague and shifting line between research and development. But many seemed to share Vannevar Bush's feeling that the industry, especially the engine manufacturers, had not yet earned the concessions they were demanding of the government. All those participating in this discussion were members of the Main Committee; their full names and titles are listed in App. B.]


Significant discussion noted as follows:

1. "(a) NACA should in the postwar period concentrate on fundamental research to advance the aeronautical sciences."

Dr. Bush: Observed that in the aircraft industry there are two groups, those building for the Army and Navy and those building for the general public.

General Echols: Said the NACA should not adopt a policy ruling it out of doing things it ought to do. We should have some policy expressing intent that the NACA will confine itself to fundamental research. The Services will handle applied [687] research and development to the extent practicable and pass some of those problems on to the industry. They are convinced the NACA wants big appropria-tions to put them out of business. They are also afraid the Government will operate all the Government-owned plants. It would be very helpful to get that fear out of their minds. It would be well to have a Governmental expression of intent to give to the aircraft people and to present before Congressional committees. There will be many problems where the Government wants something done and the only way to get it done will be to do it itself.

Dr. Briggs: This viewpoint is not peculiar to the aircraft industry. It goes throughout all industry in relation to any activities of the Government. They are anxious to have the Government conduct basic research but development they want left to themselves.

1. "(e) NACA should avoid establishment of facilities for research in those fields where industry is well equipped, i.e., radio, metallurgy, chemistry, fuel technology, etc."

Dr. Bush: We can avoid unnecessary duplication of facilities.

Admiral Pace: I have an idea that Dr. Whitney*** will consider his organization competent to do all research necessary in the engine field.

The Chairman: They want all engine research stopped on the part of the Government.

Dr. Bush: Inasmuch as the Germans have just sprung a clever, new engine on us, which our industry never thought of, their attitude does not hit me very forcibly.

2. "(a) Whether or not NACA should allow the use of its facilities for the testing (and development) for industry of specific products. The present policy of the NACA concerning the use of its facilities for investigations for the industry of specific products is summarized as follows:

"The work desired must relate to aeronautics; must necessarily involve the use of NACA facilities, i.e., adequate facilities not available elsewhere; work is paid for by firm and results are its exclusive property against remainder of industry, but are available for use of the Government.

"The larger units of industry may be expected to be in opposition to the smaller plants having access to the use of NACA facilities.

"The question is, 'In the postwar period should the NACA adhere to this policy?'

Admiral Pace: You will not want to let a strong financial concern come in and tie up all your facilities and so keep the weaker firms out. I got the impression that Mr. Grosst**** . . . did not realize that the NACA policy would permit him to come to the Committee and get necessary work done.

2. "(b) In the discussion at Cleveland with the representatives of the industry, there was considerable discussion about the sharing of public funds available for development. The industry inferred that it can use such funds to better advantage than Government laboratories in developing specific products and at the same time strengthen their own organizations."

Dr. Bush: Carried to its logical conclusion, the industry would let the NACA facilities lay idle.

The Chairman: The conclusion of one manufacturer was that the NACA should fold up. No other industry has such an organization as the NACA to help it along.

Dr. Bush: When it comes to the making of a specific product the industry can do it better than the Government.

[688] General Echols: At Wright Field we agree to that but we never make a specific product unless we have to. The industry is afraid that we will, but we have no intention of doing so generally.

The Chairman: The industry feels that it is faced with the problem of survival.

3. "There is undoubtedly some misconception on the part of representatives of the industry as to aeronautical research versus aeronautical development. The Committee's laboratories in the postwar period would be concerned primarily with aeronautical research. The discussion noted above had to do primarily with engine research. It was recognized in discussion by the members of the Committee that there is a certain overlapping between the fields of research and development."

Dr. Bush: While the industry might claim that on fundamental research they could get more results per dollar, even though we granted that were the case from the general standpoint of the public interest, there remains the fact that when the NACA gets a result in fundamental research it becomes available to a large number; whereas when a single firm in industry gets it, it becomes available only after a lag. I cannot see any argument for keeping any Government research facility idle if their use will advance the art.

Dr. Warner: The fact that no other industry has had a Government laboratory goes along with the fact that no other industry has made such rapid technical progress as aeronautics.

General Echols: Industry is always looking over its shoulder at its competitors. If their research is one step ahead of their competitors they are satisfied. It has always been apparent they are not interested in the general progress of the art. The Government, in connection with the next war, has got to look many years ahead and constantly do things which will cost money in the research field and which many times may result in nothing gained.

4."(a) Realization that with NACA research results and test facilities available to all, the best engineering organization in the engine field may lose a competitive advantage won by their own enterprise."

Dr. Bush: The results we turn out in the engine field in the next twenty years are not going to enable any firm to build an engine unless he superimposes on that knowledge his own engineering. There is no limit to the engineering one can do in improving his product. I do not see why the company that maintains its engines on a high plane will lose anything to a competitor.

The Chairman: Several of the industry in visiting Cleveland commented that the NACA was concentrating on the Allison engine to improve its performance. That hurt their feelings.

General Echols: They just happened to find the NACA working largely on the Allison engine at that time. At some other time they might see a number of 3350***** engines under study at the Cleveland Laboratory. When we have trouble with any type of engine we have to get busy and ask the NACA to push work on a single type.

The Chairman: It does not please Pratt and Whitney to see the Allison engine being benefitted by the Government.

4. "(c) Observation that NACA is leading jet propulsion and gas turbine developments in collaboration with firms previously outside the aeronautical engine field."

Dr. Bush: I do not think we need to duck that issue at all. The engine people did not do a thing on that subject or on any other unusual engine. If we brought new people into the engine field I think we have done a public service.

5. "(a) Extensive wind tunnel and engine testing facilities at Wright Field."

[689] "(b) Additional Navy facilities at Carderock, Philadelphia, and Patuxent."

The Chairman: It has been suggested to me that the NACA may be relieved of some of the routine work for the military services.

Admiral Pace: The character of the Navy facilities at Philadelphia has not changed. There is just more of it.

General Echols: The same is true of Wright Field.

5. "(c) Wind tunnel facilities at Curtiss-Wright, Pratt and Whitney, Boeing, California Institute of Technology, North American, and Lockheed."

Dr. Bush: I don't think the industry consulted the NACA about governmental policy before they built all their new wind tunnel facilities.

5. "(d) Power plant facilities at Pratt and Whitney, Wright Aeronautical, Allison, General Electric, Westinghouse, and Allis-Chalmers and proposed Packard engine test facilities at Toledo."

General Echols: The Packard Company's proposed new Toledo plant is a Reconstruction Finance Corporation proposition that was approved a long time ago. The engine industry is quite bitter about that. I don't know if we were starting again at this time we probably would not approve it. The industry is bitter about the Army putting the Packard Company into the aircraft engine business and keeping them in it.




Chairman: What we are headed toward when there is no war is to keep our technological development going at first rate speed for the benefit of the Army and the Navy. Our competitor is going to be the British. They have had five missions over here recently to study recent additions to American research facilities and to learn everything they can. The latest is headed by Melville Jones.****** They are going throughout the United States and they are frank in saying that what we have now is what they propose to build only larger and better. We have a 20-foot-altitude wind tunnel at Cleveland. They will have a 25-foot-altitude tunnel. Their program now calls for the construction of 12 wind tunnels which will constitute a great national research organization for the British empire.

Dr. Lewis: It was very interesting to me because for the first two years after the beginning of the war the British had to stop all research work and concentrate on development, and now they realize that the science of aeronautics has advanced rapidly. It is very interesting that they have been over here in several missions and have laid out a program for research and development facilities which practically duplicated what the NACA has developed in the United States. We really have an advantage at the present time. Sir Roy Fedden # recently gave a lecture.

(Dr. Lewis then read from Fedden's lecture remarks regarding the productive capacity of the British aircraft industry and how it had been increased several times and how they proposed to enlarge their research facilities.)

The Chairman: That has a bearing on the estimates the NACA may present to the Bureau of the Budget dealing with the question of how extensive should be our aeronautical research activities when there is no war. It involves a general policy concept.

General Echols: It appears that all of us are going to go to Congress with rather large postwar research budgets. It happens that the NACA is apparently one of the first that has been asked for its estimates.

[690] Dr. Lewis: I think there should be a joint effort on the part of the Army, Navy, NACA, and CAA ## in presenting their research needs and in drawing up some policy that might satisfy the industry. I cannot understand why the industry feels bitter because they must realize there is, in fact, no competition to their activity provided by any of the NACA laboratories.

Dr. Bush: There are two questions: First, on what scale should the NACA try to operate; and second, on what policy? On the matter of policy it seems to me that the needs should be formulated. At first I thought there was no need for it, but after the discussion with the industry I think there is a great need for drawing the policy which can be placed before our group for adoption for our own guidance and then tell the industry where to stand. There is no necessity for doing that at once. I suggest that it would be a good idea to have a subcommittee work on that so that when we next meet we can have something before us in definite form.

The Chairman: Would it be your idea that General Echols, Admiral Pace, possibly Dr. Warner, and Dr. Lewis- could these four people as committee members draft a policy for the NACA?

Dr. Bush: I would suggest that you, Mr. Chairman, sit in with the group. I would make a motion that such a committee be asked to draw up a resolution to be presented at the next meeting; that the four gentlemen named study and prepare a statement on postwar policy for us.

The motion was duly seconded and carried and the Chairman announced that he would ask Dr. Lewis to serve as chairman. The other members to be General Echols, Admiral Pace, and Dr. Warner.



35. "Notes of discussions at meeting of National Advisory Committee for Aeronautics, April 26, 1945, "undated.


[At the semiannual meeting of the NACA in April 1945, the issue of industry representation on the NACA and its technical committees arose. In contrast to the meeting summarized in document 34, industry representatives were present for this discussion. Still, the NACA yielded nothing on industry representation, one of the most troubling issues to face the Committee in the immediate post-war years. The tenor of the discussion shows how adamant the NACA was on this issue- and why. All those present, in addition to George Lewis and John Victory, were members of the NACA Main Committee; their full names and titles appear in App. B.]


Subject: Aircraft industry point of view regarding representation on NACA.

Mr. Burden: We had a discussion with members of the industry- Don Douglas, Gene Wilson and Bob Gross.### They expressed a desire for closer liaison with NACA activities than has been possible during wartime. They specifically made three suggestions: First, representation of the industry on the NACA working committees. The industry now is not really informed about what is going on. They suggested it might be possible to have their nominations made by the industry and let the NACA pick members from their nominees.

Mr. Littlewood: My thought is if the industry were to operate through its commercial agency, the Aeronautical Chamber of Commerce, appointments would not be directly representative because of geographical situations. A national organization [691] which better represents the research side is the Institute of the Aeronautical Sciences, and I think that could be suggested to the Chamber as the agency to nominate people to work with the NACA.

Dr. Bush: That might work on an informal basis. It might be embarrassing if it became understood that the NACA could not function without the industry nominations.

Dr. Hunsaker: If we had suggestions from the industry we might select from such suggestions. I had a discussion with Don Douglas on the West Coast recently. Douglas said the committee members from his company were employees of his corporation chosen by the NACA without his knowledge or consent; that what went on in NACA subcommittees was known only to the members thereof. The industrial units do not get any results until a report is made- what went on was confidential discussion between the members of the committee. He said the thing to do was to put on the committees accredited representatives of the industry who would be their watchdog on the committee and would report to all of the industry democratically what was going on and what was planned. I thought that was outrageous- that our committees would shrivel. We have built up over the years quite free and frank discussions between the people who are normally competent & exchange a good deal of advice and counsel and give us on the Main Committee advice as to the direction on which we should go. The appoint-ment of industry representatives sounds very innocent, but if they are appointed for the purpose of being representatives, it would upset our applecart.

Dr. Bush: I feel strongly that we cannot get into the position where industry can tell us who we may have on the committees. It would be fatal.

Mr. Burden: Douglas proposed that we should have the veto power.

Dr. Hunsaker: Did he propose that the people would report back to their compa-nies what was going on?

Dr. Warner: They want members responsible to the industry as a whole.

On request of the Chairman Mr. Victory gave an analysis of the subcommittee membership, stating that there are six major and eighteen subordinate technical com-mittees, with a gross membership of 244, of whom approximately one-half are from industry, including twenty airplane-manufacturing firms, six engine manufacturers, and twenty-one other allied or supporting industries.

Dr. Hunsaker: Should we form an industrial consulting committee?

Dr. T. P. Wright: I think we ought to adopt this first point.

Dr. Bush: On some things it would be very helpful to have a subcommittee member from one industry visit and report to other industries, but it might be fatal.

Dr. T. P. Wright: We are asking an aerodynamics committee member from industry to visit other firms and bring in information.

Mr. Littlewood: The industry wants early access to the problems under discussion. Maybe if the subcommittees were to put out interim reports more frequently that might answer the need.

Dr. Bush: If we are having close contact with some manufacturer, it would be a big advantage to him to have up-to-the-minute information which he might incorporate in his product.

Dr. Hunsaker: You have Colonel Carl Greene#### at Langley Field, and the industry's designers go down there, live in his office, and sit in with our laboratory heads.

Mr. Burden: I think there must be some personal contact. The industry is unhappy about it. We will save ourselves a lot of trouble in the long run. I do not see why it should run us into considerable difficulties.

[692] Dr. T. P. Wright: I suggest that the industry nominate three East Coast and three West Coast representatives for each committee and we select one and give him instructions.

Dr. Hunsaker: Would they be members or observers? A mere observer would spoil discussion.

Dr. Bush: I suggest the subcommittees might have meetings with the industries as guests. I think our subcommittees must have members who take an Oath of Office and represent only the United States Government in any units of the industry.

Dr. Hunsaker: Suppose we asked the Aeronautical Chamber of Commerce "Will you suggest three names for our consideration?" on a given committee. The committee controls its appointments. If a member does not behave, we can bounce him.

Dr. Lewis: Would that prevent the NACA from appointing others from industry?

Dr. Hunsaker: They would be appointed from the Institute of the Aeronautical Sciences.

Mr. Burden suggested that a special committee be appointed by the Chairman to consider the matter and report at the next meeting. The Chairman asked if there was any objection. Hearing none, he announced he would appoint a special committee composed of Dr. Lewis, Dr. T. P. Wright, and Mr. Littlewood.

Mr. Burden: Their second suggestion was the appointment of an advisory commit-tee of the heads of industry who could have an opportunity to sit down with the NACA and talk over general problems like we did last year at the Cleveland and Ames Laboratories. In doing that we could build up good personal relations.

Dr. Hunsaker: Then they would come prepared to discuss our programs. We practically invited that kind of relation last year by asking them to visit the Cleveland and Ames Laboratories and to discuss problems with them. I agree that where we are badly off in our public relations is with the financial heads of the large manufacturers. You, Burden, might head a panel to recommend who in the industry might be honored by our invitation. I suppose our transport industry should also have representation.

Mr. Littlewood: I suggest that the Vice Presidents in charge of Engineering should be the representatives.

Dr. Hunsaker: Will you, Burden, be a panel of one to make a proposal?

Mr. Burden: Yes, but I would like to work with you and Lewis on that.

Dr. Hunsaker: It is agreed that at the next meeting we will consider two methods of administration and organization that bear on our relations with the industry.

Mr. Burden: The third matter in which industry is concerned is the appointment of a member of the industry on the Main Committee as an industry representative. They suggested that the president of the Aeronautical Chamber of Commerce be a statutory member. We stated we did not agree with that.

Dr. Hunsaker: The president of the Aeronautical Chamber of Commerce would be an ex officio statutory member? Amend the law? Is that it?

Mr. Burden: Yes. That is it.

Dr. Bush: I do not think Congress would like that.

Mr. Victory: I suggest the importance of the members keeping in mind that the NACA is a governmental organization created by law as such to represent the govern-ment's interests, and that there is great danger of the Committee's losing its standing and influence if it becomes known that it is a spokesman for industry. Some years ago the Aeronautical Chamber of Commerce appointed a technical committee to prepare a program of problems which the Chamber recommended that the NACA investigate.

[693] The NACA considered the matter, agreed that the problems were good and worthy of investigation, and submitted a supplemental estimate of appropriations to finance the work. That was the only time in the entire history of the NACA that one of its recommendations was flatly rejected and it drew a rebuff from the Bureau of the Budget because, as the Bureau expressed it, the NACA was not established to be a special pleader for industry.

Mr. Burden: I don't think we ought to do it.


36. "National Aeronautical Research Policy," approved 21 March 1946.


The result of almost two years' discussion and negotiation (documents 33-35), this policy statement sets forth the division of responsibilities and functions within the American aeronautical community. Though the NACA assumed no political role beyond coordination of parallel research activities, this document is nevertheless as intensely political as the parallel policy statement published by the Committee after World War I (document 18). For example, the Committee clearly was arguing for sustained appropriations, even though the war was over, and the division of functions among major American aeronautical institutions implicitly excluded private aviation and small inventors, operators, and manufacturers from NACA consideration. Furthermore, the NACA conceded more here to the aviation industry than ever before.]


1. Experience since the establishment of the National Advisory Committee for Aeronautics by the Congress in 1915 has shown that the value of the airplane for national defense and for commerce has directly followed the evolution of an advancing technology based on research. Research made rapid strides as more facilities were provided for the NACA. The Army and Navy explored military applications of NACA fundamental research results with the aid of their increased facilities for testing and evaluation. The aircraft industry, by the exercise of great initiative and technical competence, developed superior airplanes of both military and civil types to meet ever-increasing performance requirements.

2. The effects of accelerated enemy research and development in preparation for war helped to create an opportunity for aggression which was promptly exploited. This lesson is the most expensive we ever had to learn. We must make certain that we do not forget it.

3. During the war, the NACA has greatly expanded its research facilities at Langley Field, Moffett Field, and Cleveland, while the Army and Navy have correspondingly increased their facilities for testing and evaluation. Furthermore, the aircraft industry has been able to provide extensive development facilities of its own. As a result, American airplanes are today superior in most respects.

4. This lead may or may not be continued in the post-war period, depending on whether the present facilities in the country are used to full effect to advance the science and the technology of aeronautics. Results already obtained make it apparent that there are further opportunities for substantial improvement in the performance of aircraft and equipment which can be realized only by vigorous research and development programs.

5. It is possible to assume that the United Nations will, by repressive measures, eliminate hostile competition in the air. Nevertheless, it is essential so to continue research as to assure American leadership in military aviation development. It is moreover certain that between the United Nations vigorous commercial competition will take place. In fact, we already are informed of extremely ambitious plans to surpass present American research equipment, obviously in a desire to excel in the air.

6. The Committee believes it to be in the public interest to foster a greatly increased civil use of the airplane, for domestic and international airlines and for [694] private operation. A vigorous civil aviation can affect favorably our domestic and international relations, both economic and cultural. At the same time it will contribute to national security by the support of a reserve of airplanes; operating, development, and manufacturing facilities; and civilians trained in the skills which are critical in time of war.

7. The rate of growth of civil aviation will depend on the rate at which improve-ments in safety, performance, reliability, utility, and economy can be realized. However, to realize such improvements, research must solve some difficult problems associated with operations over extended ranges of distance and altitude, aggravated by the extension of airlines over areas of unusual weather and terrain.

8. Some of the results of war research can be applied by the aircraft industry directly to new designs of civil airplanes. In many cases, however, practical applications have yet to be discovered and require further research directed toward the solution of specific problems. Neither the airlines nor the manufacturers can be expected to solve these problems quickly without the assistance of intensive research by the NACA and development by the industry.

9. The NACA should, therefore, endeavor to direct an increasing proportion of its research effort to the technical problems of civil aviation with a view to their practical solution.

10. Experience clearly indicates that in time of peace the application of research results to military and naval objectives is extremely important. Possible military applications must be explored by continuous experiment and testing by professional soldiers and sailors as a life work, and the developments of industry must be evaluated by the military users. Such exploration and evaluation require the use of the facilities now available to the Army and Navy.

11. The public interest requires that effective use be made of existing facilities for research, development, and evaluation, and that they be kept modernized and new ones added as the progress of the art requires. Outmoded facilities should not be used simply because they exist. The results of research conducted at public expense should be made available to manufacturers and operators in such a manner as to stimulate the growth of healthy competition in the supply of goods and services.

12. It is recommended that the Army Air Forces, the Bureau of Aeronautics of the Navy Department, the Civil Aeronautics Board and the Civil Aeronautics Administra-tion of the Department of Commerce, and the NACA follow, in so far as may be practicable, the following general policy considerations in the post-war utilization of research, experimental and testing facilities of the Government and their relation to the development facilities of the aircraft industry.

A. Fundamental research in the aeronautical sciences is the principal objective of the NACA. Such research is directed toward the solution of the problems of flight and results are promptly published. In exceptional cases research results of potential military importance may be withheld from publication.

B. Research of the NACA is not considered completed until results are tested by sufficient practical application. However, NACA research will not include the development of specific aircraft or equipment.

C. Research programs of the NACA are formulated in close collaboration with technical personnel from the Government agencies concerned and from industry through membership on appropriate subcommittees. Members of all technical subcommittees of NACA are appointed as individuals especially qualified in their particular fields.

D. The research facilities of the NACA may be used upon request by a Govern-ment agency in evaluation of specific aircraft and equipment, whenever facilities avail-able to that agency are inadequate.

[695] E. The research facilities of the NACA Laboratory may be used to assist private individuals and corporations whenever other facilities are not available and NACA facilities are available provided that the investigation is considered by the NACA to be worth making. If the investigation is considered by the NACA to be in the public interest and the private individual or corporation agrees, the work may be undertaken at public expense and the results published. If the investigation is primarily of private interest, the cost should be met by those requesting assistance and the results reported only to them.

F. Application of research results in the design and development of improved aircraft and equipment, both civil and military, is the function of the industry, assisted as may be necessary by contracts for experimental articles, placed in a manner to stimulate competition for quality. It is recognized that the encouragement of competitive engineering organizations is essential.

G. The evaluation of military aircraft and equipment developed by the industry, and the exploration of possible military applications of research results are considered to be the function of the Army and Navy.

H. Expedition of the practical use in civil aeronautics of newly developed aircraft and equipment, in so far as Government assistance may be necessary, is considered to be the function of the Civil Aeronautics Administration.

I. The NACA normally will use its own research facilities, but will contract with university and other private research organizations for work in special fields where outside facilities and competence are to be found. Likewise, the facilities and competence of the National Bureau of Standards, Forest Products Laboratory, and other Government research centers will be used by the NACA whenever practicable.

J. Unnecessary duplication of facilities and effort will be avoided by adherence to the principles stated above, but for important problems whose practical solution ap-pears to be especially difficult, parallel attack by several independent research teams is necessary. In such case, the NACA, the aircraft industry, Army, Navy, and Civil Aeronautics Administration, Department of Commerce and individual scientists and inventors may work on various aspects of the same basic problem. Such parallel attack must be coordinated, and it is the policy of the NACA to achieve such coordination through the medium of subcommittees of experts representing all concerned.



37. National Advisory Committee for Aeronautics, "A Proposal for the Construction of a National Supersonic Research Center, "April 1946.


[The advent of jet propulsion during World War II raised the prospect of super-sonic flight, even though the "sound barrier" was not broken until 1947. Wind-tunnel research at supersonic speeds required enormous amounts of power, demands that soon would have overtaxed. local utilities at existing NACA laboratories if the Committee had built all the tunnels it envisioned in the immediate postwar period. Prompted by news that the Army Air Forces were planning their own supersonic research facility, the NACA rushed into print with this proposal for a national supersonic research center. This was the Committee's opening move in a three-year struggle that culminated in the National Unitary Wind Tunnel Plan Act of 1949. In the course of the struggle, this plan was at first expanded to even more grandiose proportions, and was then reduced drastically at the hands of the Bureau of the Budget and Congress. The NACA never got its national supersonic research center; events were to prove that it never needed one.]




Recent trends in the advancement of the aeronautical sciences have emphasized the urgent need for accelerated research on aerodynamic and propulsive problems associated with aircraft traveling at speeds greater than the speed of sound.

Supersonic research facilities of the size and speed required for conducting fundamental research on these problems are not available, and the utility requirements of such facilities cannot economically be met at any one of the existing laboratory sites of the National Advisory Committee for Aeronautics.

It is proposed that steps be taken at an early date to obtain authorization for the National Advisory Committee for Aeronautics to begin construction of a National Supersonic Research Center on a site to be selected by the Committee.

Preliminary estimates of the cost of the Supersonic Center total $162,000,000 for the first five-year period. The initial request for authorization would include appropriation requests totaling $5,500,000, of which amount $1,500,000 would be required for preliminary design studies and $4,000,000 for initiating construction during the first year.




Advancement of the natural sciences is the key to national security and prosperity. In a military sense, national security demands superiority in the air. Military leaders agree that existing air weapons will be obsolete when the barriers to supersonic flight have been overcome. Experience has shown that a time lag of from 5 to 10 years occurs between the discovery of a scientific principle and its practical application. Fundamental research must therefore substantially lead development. In the interests of defense and preservation, our nation must be the first to master the science of supersonic flight. To this end a comprehensive integrated program of supersonic research must be initiated and accelerated, and adequate facilities for conducting the research must be provided.

The National Advisory Committee for Aeronautics was established by Act of Congress in 1915 "to supervise and direct the scientific study of the problems of flight with a view to their practical solution." In fulfilling this responsibility the Committee has conducted fundamental research at its three laboratories located at Langley Field, Moffett Field, and Cleveland. These laboratories are largely devoted to research at subsonic speeds and were instrumental in providing the basic research information that led to the successful military airplanes of the past war. Research of limited scope has also been conducted at supersonic speeds. Existing facilities are in no way adequate to provide a sound scientific foundation for supersonic flight. Additional equipment is required if leadership in this field is to be achieved.

The National Advisory Committee for Aeronautics has been intensively studying supersonic research problems and the additional research facilities necessary for their solution. A summary of this study, including an outline of suggested new research equipment and a method of immediate approach to the problem, is given in this report.




Research at supersonic speeds is in an embryonic stage comparable to the state of development of subsonic research in the early days of flying. A brief statement of the scope of the research to be accomplished and a description of research techniques will indicate the present state of the science and provide justification of the methods proposed to accelerate research activity.

Research Problems. Research in all fields of aeronautics is directed toward the ultimate solution of the practical problems of flight. In this respect the general [697] research objectives in the subsonic and supersonic regimes are similar. The solutions of research problems, however, are not similar. In subsonic flight, pressure disturbances are propagated ahead of a body and streamlines are deflected so as to pass smoothly over it. In contrast, at supersonic speeds disturbances are not propagated upstream, and the streamlines are abruptly deflected at the nose of the body by flow discontinuities called shock waves. The essentially different flow mechanism of the supersonic range requires new solutions for the major aerodynamic and propulsion problems.

Many undeveloped concepts exist in the new field that require study of:

1. The origin, propagation, structure and interaction of shock and expansion waves.
2. The development of laminar and turbulent boundary layers and their behavior in the presence of self-induced shock and expansion waves.
3. Upstream propagation of disturbances through wakes and boundary layers and the nature of separation effects.
4. The nature of development of pressures on wing surfaces as affected by airfoil contours, wing plan forms, and other geometric variables.
5. Pressure distributions and origin of drag for bodies of revolution as affected by the geometry of the body.
6. The fundamentals of interaction of wing-body combinations.
7. Aerodynamic variables in the transition range from subsonic to supersonic flow.
8. Fields of flow ahead of and behind lifting surfaces and bodies.
9. Fundamental propulsion arrangements for aircraft.
10. Aero-thermodynamic relationships for internal flow systems at supersonic speeds.
11. Non-stationary flow phenomena.
12. Surface temperatures at supersonic speeds and basic methods for heat dissipation.

The foregoing list includes but a minor fraction of the many fundamental research problems that must be investigated. In addition there are broad fields of systematic research on each of the various components of supersonic aircraft that will provide a firm basis for the practical application of supersonic principles and lead to the formulation of new concepts.

The scope and variety of the enumerated research problems provides only a partial indication of the magnitude of the research that must be accomplished; each of the problems must be investigated over a wide range of airflow Mach numbers and Reynolds numbers. Flow Mach numbers in the range from 1 to 10, that is in the speed range from one to ten times the speed of sound, must be thoroughly studied in the next few years to provide the basis for design of piloted and pilotless aircraft. Flight at speeds greater than ten times the speed of sound must be tentatively explored for bodies that are to be flown in the upper limits of the atmosphere.

The effect of Reynolds number, or scale effect, must be investigated for a range of various size aerodynamic bodies, from small compressor blades to wings of large man carrying aircraft. Preliminary investigations on bodies of revolution have already shown that the scale of the body has an important effect on its aerodynamic characteristics. Whether the flow in the boundary layer is laminar or turbulent depends upon the scale of the tests and the effect of interactions of shocks with these two types of boundary layers has tentatively been shown to be different.

The necessity for adequately exploring the broad range of flow Mach numbers and Reynolds numbers with models of sufficient size so that aircraft and engine geometry can be accurately reproduced introduces the real urgency for more extensive research facilities.

[698] Research Techniques. Experimental techniques utilized in subsonic and supersonic research are similar in character, thus parallel types of research facilities are employed in the two branches of the science. Principal techniques include:


1. Wind-tunnel investigations.
2. Flight studies with piloted aircraft and with pilotless aircraft and bodies.
3. Drop tests of bodies from high altitude.
4. Electric and hydraulic analogies.

These research techniques are all useful and continuous effort is exerted to extend their usefulness by development of instrumentation.

The wind tunnel, however, is by far the most important aeronautical research tool. The major portion of all aeronautical research data upon which the science of flight is based was obtained in wind tunnels. The advantage of the wind-tunnel technique results from the expediency with which extensive measurements can be made under widely varying test conditions. Modern subsonic wind-tunnel technique provides instrumentation for recording more than a thousand simultaneous research measurements.

Acceleration and intensification of supersonic research activity requires wind tunnels in sufficient number and of adequate size and speed so that the useful wind-tunnel technique can be fully exploited.

Wind tunnels for subsonic and supersonic research, although generally similar in character, possess different degrees of flexibility with reference to possibilities of varying operating speeds and size of models that may be investigated. Flexibility in the use of supersonic wind tunnels is determined by the following requirements:

1. Models must be small enough in cross section so that a normal shock resulting in conversion of the flow from supersonic to subsonic will not occur in the test section, and
2. The models must be sufficiently short so that supersonic waves generated at the nose of the models are not reflected back from the tunnel walls on the rear of the models.
Flexibility in the design of supersonic wind tunnels is limited by:
1. Wind-tunnel compressor characteristics.
2. The design requirements of the mechanism for changing the wind-tunnel Mach number.
3. Model support design requirements.

These considerations define the range of Mach numbers and Reynolds numbers that may be investigated in a single wind tunnel, and provide the basis for establishing the minimum number and types of supersonic wind tunnels required for adequate coverage of the broad fields of research.

Facilities for applying other research techniques are also required to supplement the wind-tunnel research and provide the evaluation of final results.




Supersonic wind tunnels in operation and under construction by the National Advisory Committee for Aeronautics are as follows:


Size of test section

Maximum Mach number






4 by 18 inches




9 inches



[699] Ames

8 by 8 inches




1 by 3 feet




18 by 18 inches


Aerodynamic & Propulsion




Aerodynamic & Propulsion





1 by 3 feet




2 by 2 feet


Aerodynamic & Propulsion


4 by 4 feet




6 by 6 feet




8 by 6 feet


Aerodynamic & Propulsion


The 4- by 18-inch tunnel at Langley Field is of the induction nonreturn type and can be used only for short periods of time. It is operated by discharging compressed air from a large tank through ejector nozzles, thereby inducing high-velocity air flow in the tunnel test section. The 9-inch tunnel is of the direct-action return type, and is driven by a 1,000-horsepower axial flow compressor. These tunnels are used for preliminary investigations of the aerodynamic characteristics of very small models in the supersonic speed range.

The 8- by 8-inch tunnel at Ames is of the nonreturn type and is powered by three compressors totaling 4,500 horsepower. This tunnel serves as a pilot tunnel for designing wind-tunnel nozzles and diffusers. The existing 1- by 3-foot tunnel is of the single return type and is driven by compressors with a total installed horsepower of 10,000. It is used for aerodynamic investigations of small airfoils and bodies at supersonic speeds and for fundamental studies of supersonic-flow phenomena. The pressure in the tunnel can be varied to permit research to be conducted over a range of Reynolds numbers.

The supersonic tunnels at Cleveland are operated by the equipment already provided for evacuating the Altitude Wind Tunnel. During periods when the Altitude Wind Tunnel is not in operation, its large exhauster pumps are used to draw air through the supersonic tunnels. The primary purpose of these tunnels is to investigate the fundamentals of small-scale propulsive systems suitable for powering supersonic aircraft.

The Ames 1- by 3-foot and the Cleveland 2- by 2-foot supersonic wind tunnels now under construction will extend the speed range available for small-scale aerodynamic and propulsion research. The other three wind tunnels under construction represent the Committee's most advanced effort toward the construction of equipment for supersonic research. These tunnels are a first approach to the problem of obtaining facilities that will provide results on models of larger sizes, higher Reynolds numbers, and higher Mach numbers. The Langley 4- by 4-foot wind tunnel is a closed-return tunnel and is equipped with a 6000-horsepower drive motor. It operates at reduced pressure simulating altitude conditions.

The Ames 6- by 6-foot wind tunnel is generally similar in arrangement to the Langley 4- by 4-foot tunnel, but operates at higher pressures with resultant higher Reynolds numbers and a greater power absorption. Motors delivering 50,000 horsepower drive the larger Ames tunnel. Both wind tunnels are adapted to aerodynamic [700] research on two-dimensional and three-dimensional models considerably larger in size than can be tested in existing supersonic wind tunnels.

The 8- by 6-foot supersonic wind tunnel now under construction at the Cleveland laboratory is a nonreturn tunnel designed specifically for research on supersonic propulsion systems. Models of engines will be operated under full power at simulated conditions of flight and at speeds exceeding 1300 miles per hour.

In summary it may be stated that the use of the available research facilities and those under construction will result in the attainment of further knowledge of the mechanism of supersonic air flow, will lead to a better understanding of the requirements for improved airfoils, body shapes and propulsion systems, and will result in the development of improved instrumentation and testing techniques. The results of research in these wind tunnels will provide a step in the evolutionary process leading toward a complete understanding of the characteristics of full-scale supersonic aircraft. These facilities, however, are subject to the following limitations:

1. Many important research problems associated with stability, control, flight-handling characteristics, and propulsion cannot be investigated at Reynolds numbers approaching those encountered in flight nor can certain special research problems requiring models of larger size be adequately investigated.
2. No equipment exists or is under construction for research at Mach numbers above 4.5, whereas a comprehensive and integrated program of research should include facilities for investigation over a range of Mach numbers up to at least 30.




In order to meet the existing and urgent need for more advanced supersonic research facilities, it is proposed that a National Supersonic Research Center be constructed, the first phase of the construction to be as follows:

1. Supersonic wind tunnels of comparatively large scale to cover the range of Mach numbers of 0.8 to 10 for both aerodynamic research and research on propulsion systems.
2. Supplementary facilities and services for exploring at smaller scale the fundamentals of flows at Mach numbers as high as 20 to 30.
3. Facilities for full-scale research on propulsive systems that use normal fuels or hazardous fuels.

Equipment. Preliminary studies of the proposed equipment indicate that it is not feasible at the present time to attempt the design and construction of wind tunnels for full-scale research on complete airplanes at supersonic speeds. In wind tunnels that can be built at this time, however, it will be possible to conduct research at Reynolds numbers approaching full-scale values and to investigate many aerodynamic and propulsion elements at full-scale.

The following supersonic wind tunnels are recommended for construction:


Height of Test Section

Mach Number




20 ft. to 30 ft.

0.8 to 1.6



10 ft. to 15 ft.

1.5 to 2.6


6 ft. to 10 ft.

2.0 to 3.0


6 ft. to 10 ft.

3.0 to 4.8



6 ft. to 10 ft.

4.8 to 7.0


6 ft. to 10 ft.

7.0 to 10



10 ft. to 15 ft.

1.5 to 2.6



[701] A- Aerodynamic research, primarily on configurations, stability, and control, and factors affecting maneuverability of piloted supersonic aircraft.

B- Research on aerodynamic elements and configurations of supersonic piloted and pilotless aircraft, and on the aerodynamics of propulsion.

C- Aerodynamic research for new concepts, for basic design data and for specific information, on pilotless aircraft particularly of the rocket type.

D- Propulsion research permitting duplication of internal and external conditions of power plants and their installations under the range of altitude and temperature conditions of interest.

...Each of these four wind tunnels will require drive motors of approximately 450,000-horsepower capacity.

These major facilities will be supplemented with less powerful but important aerodynamic research facilities and services for exploring the physical nature of flows at Mach numbers as high as 20 to 30.

Essential investigations on propulsion systems for supersonic flight will be carried forward in special facilities that will provide sufficient dry refrigerated air to operate jet engines of more than 40,000 pounds thrust. Since altitude exhaust facilities will also be installed, the internal flow systems of large engines will be subjected to conditions duplicating actual flight at supersonic speeds.

One of the extremely promising fields of research on engines for supersonic flight is the study of fuels of high energy content per unit of volume. It is characteristic of such fuels that the energy is released at a rate which greatly, exceeds the heat output from the combustion of normal hydrocarbon fuels. Until such time as the new types of fuels can be fully investigated and brought under proper control, an element of danger is involved in their handling. For this reason a Hazardous Fuels Laboratory will be provided at some distance from other facilities at the laboratory site, and it will have suitable devices to protect in every possible way the safety of the operating personnel.

Instrument-research facilities are included in the program so as to ensure proper facilities for investigations of research instruments and techniques. The true value of supersonic research equipment can be realized only if the scientist has at his disposal an accurate and reliable means for measuring the many complex physical phenomena involved in the investigation. Because of the many new problems encountered in advanced research on supersonics, numerous new instruments must be devised and made available to the aerodynamicist.

In addition the program contemplates the construction of the necessary service and administrative facilities. A tentative plan for the arrangement of the proposed facilities is presented on the following page.

Personnel. In research, the quality of the workers is all important. Key men for the proposed National Supersonic Research Center are available in the present NACA staff, but an intensified recruiting and training program will be required to ensure that a sufficient number of highly qualified specialists will be available when the new facilities are completed. It is proposed to accomplish this through the existing training program within the NACA and by means of arrangements with universities for advanced studies in special fields of applied science.




The basic requirements of a site suitable for the construction and operation of the research equipment herein proposed may be summarized as follows:


1. Continuous availability of low-cost electric power in accordance with the following schedule:

Within 3 years: 300,000 kilowatts, 600,000,000 kilowatt-hours per year

Within 5 years: 500,000 kilowatts, 1,000,000,000 kilowatt-hours per year

[702] Ultimate: The power potential of the area within transmission distance of the laboratory site shall be capable of development so as ultimately to provide power in quantities several times the figures indicated for the five-year period.

2. Cooling water, sufficiently clean, pure, and cool for use in heat exchangers, in adequate quantity up to 300,000 gallons per minute.

3. Adequate land for the construction of the research facilities in an area where the topography of the adjacent terrain is suitable for flight research with piloted supersonic aircraft.

4. Climatic conditions which will provide clean, dry air and good flying weather.

5. Adequate transportation and communication facilities, access to industrial centers.

6. An area near the site suitable for the development of a community, or the expansion of an existing community, to provide satisfactory living conditions for personnel.

No one of the Committee's three existing laboratories can meet the site requirements. Preliminary surveys indicate that a site meeting all requirements may be found in at least one of the following areas:

1. The Columbia River area in the vicinity of Grand Coulee Dam, Washington.

2. The Colorado River area in the vicinity of Boulder Dam, Nevada.

3. The Central California area served by the Pacific Gas and Electric Company.

The final selection of a site must be based upon a thorough study of possible sites in all three areas. The advantages and disadvantages of each possible site must be analyzed in detail on the basis of engineering, economic, and environmental consider-ations.




The large size of the utility installations and research facilities proposed for the National Supersonic Research Center presents a number of unprecedented problems in engineering design. It is estimated that a period of approximately one year will be required for preliminary engineering design studies to provide adequate information for the preparation of detailed specifications. It is proposed to accomplish the preliminary studies by an integrated program involving pilot investigations, detailed analysis, and study by Committee research experts, supplemented by the services of experienced industrial engineering firms and consultants employed under contract.

It is proposed that funds be requested in an amount adequate to permit the assignment by the Committee of an initial staff of 30 employees to this project to be increased gradually during the period of one year to approximately 210. This staff will be engaged (1) on research investigations using pilot equipment for the solution of basic design problems, (2) on the preparation of design requirements and design specifications, (3) on the design of certain equipment and instrumentation which requires a specialized knowledge of research, and (4) in performing the essential planning, administrative, and coordination functions involved in a construction project of this character.

Concurrent with these activities, arrangements will be made to enter into contracts with competent industrial engineering firms and consultants to furnish detailed design information including plans and specifications on many phases of the project. The use of outside services in this manner, particularly on such items as the optimum design and layout of utility installations, road construction, land improvements, water-purification and -cooling systems, and drive motor and compressor construction, is considered essential to ensure the construction of a workable and economical laboratory.

[703] The [following] chart . . . indicates the estimated schedule for the design and construction of the facilities proposed for the Supersonic Center. It is estimated that design information on some phases of the utility system will be available in time to begin construction during the first year.

The amounts recommended under (a) and (b) above represent the best estimates that can be made at this time of the sums that could efficiently be obligated during the fiscal year 1947. As preliminary design studies are completed, the Committee will be in a position to prepare and submit accurate estimates of the appropriations that will be required annually to complete the project.


Tentative schedule for design and construction, National Supersonic Research Center, during first 5-year period.

Tentative schedule for design and construction, National Supersonic Research Center, during first 5-year period.


38. Langley Memorial Aeronautical Laboratory, "Appraisal of German Research during the War Relative to that of the NAGA," [Oct. 1946].


[In response to widespread suspicion that the NACA had been bested by the Germans in aeronautical research just before and during World War II, the Langley laboratory staff prepared this comparison, based on the NACA's record and on investigations made in 1945 and 1946 into German achievements. Although this analysis does provide a fair summary of aeronautical progress in World War II its evaluation of the relative achievements of the Germans and the NACA must be taken with caution. The tone is so defensive and the treatment so one-sided (for example, the discussion of jet propulsion) that, in keeping with Jerome Hunsaker's advice, the analysis was never published.]




In general, the major portion of all the airfoil research carried out by the Germans was carried out either on NACA airfoil sections or on modified NACA airfoil sections. Furthermore, the methods used for modifying the airfoil sections were those previously developed by the NACA. The Germans have not developed methods of relating airfoil shape and angle of attack with pressure distribution to the degree of refinement that has been achieved by the NACA, nor have they correlated the aerodynamic characteristics of airfoil sections with their pressure distributions as closely as has been done by the NACA.

[704] The problem of reducing skin-friction drag of wings by maintaining extensive laminar flow in the boundary layer was the subject of much research in many countries before and during the war. The Germans expended considerable effort on theoretical investigations of the stability of laminar boundary layers. Schlicting##### made some of the most significant contributions to this subject. The final results of Schlichting's calculations indicated that laminar boundary layers in a region of favorable pressure gradient were stable to much higher Reynolds numbers than those in unfavorable gradients, but that, in any case, if transition occurred when the boundary layer first became unstable, the extent of laminar flow obtainable at flight values of the Reynolds number was relatively unimportant. This result is to be contrasted with the results of NACA investigations which showed extensive laminar flow on smooth low-drag airfoils in a low-turbulence airstream up to Reynolds numbers of more than 40 million.

As an extension of Schlichting's work, a number of theoretical investigations were undertaken in Germany to determine whether or not the lower critical boundary-layer Reynolds number could be increased by means of boundary-layer suction. These theoretical investigations indicated that the application of continuous suction, such as might be obtained through a porous surface, might permit laminar flow to be obtained at nearly any flight value of the Reynolds number. No experimental work was done, however, either to develop suitable porous surfaces or to check the theory. NACA investigations conducted prior to our entry into the war indicated that the use of multiple suction slots did not reduce the difficulties associated with maintaining sufficiently smooth surfaces for laminar flow at high Reynolds numbers.

Perhaps because the results of Schlichting's calculations indicated the improbability of obtaining significant amounts of laminar flow at useful Reynolds numbers, the Germans appear to have done comparatively little research work on low-drag airfoil sections such as those systematically investigated by the NACA. Several early type NACA low-drag airfoil sections, descriptions of which fell into German hands after the fall of France, as well as several German-designed laminar-flow sections which were similar to the early NACA types, were tested. In nearly all cases, however, the German airfoils had unnecessarily small leading-edge radii and poor trailing-edge shapes with the result that the observed maximum lift coefficients were low. Furthermore, none of the wind tunnels in which tests were carried out had turbulence levels sufficiently low to achieve large extents of laminar flow in the practical flight range of Reynolds numbers.

In an effort to increase the maximum lift coefficients obtainable with plain airfoil sections, a considerable amount of German research was concerned with the development of high-lift devices. Although some rather unusual configurations were tried, most of the trailing-edge high-lift devices tested, such as the plain, split, slotted, and double slotted flaps, were similar to those investigated by the NACA. .

Further increases in the maximum lift coefficient were obtained by means of boundary-layer control. Investigations of both blowing and sucking slots were made in Germany and, in some cases, more than one slot was used. These investigations generally paralleled those of the NACA, although the configurations were naturally not identical.

At about the start of the war the Germans recognized the applicability of swept wings for flight at high Mach numbers, and most of their subsequent three-dimensional wing research during the war concerned the properties of such wings. They noted the characteristic boundary-layer cross flows and the poor stalling, and spent considerable effort in testing various fixes, such as boundary-layer control, leading-edge slats and flaps, fences, and washout. NACA wing research until 1945 was concerned mainly with [705] unswept designs for particular purposes and with correlation of section and wing characteristics, with special emphasis on wings having high-speed sections; and swept wings had been studied mainly with regard to their use on tailless airplanes. When, in 1945, the development of suitable power plants made transonic flight appear possible, the NACA independently recognized the applicability of swept wings for high-speed flight. Immediate attention was directed to research on such wings with the result that the German data, when they became available, were supplemented by NACA data at transonic speed where no German data were obtained.

With regard to the calculation of span-load distributions on swept wings, methods that satisfy the downwash condition at the three-quarter chord line were developed both by the NACA and in Germany. The theory of the ring-shape airfoil was also developed in both countries. Lifting-surface solutions developed by the NACA seem to have had no counterpart in Germany.

The German studies of subsonic compressibility effects on airfoil sections were very similar to ours-for example: (1) in the derivation of accurate potential flows containing a small supersonic region, and in the demonstration that such flows could not be derived above a certain Mach number, (2) in the accurate computation by the Ackert###### method of the compressible flow about a Joukowski####### airfoil, (3) in efforts to strongarm solutions for airfoil flows with shocks, and (4) in the computation of extensive tables of hypergeometric functions for use in compressible-flow computations. Their experimental high-speed section data, of which a considerable amount was obtained, was similar to that obtained in the NACA 11-inch and 24-inch high-speed tunnels, and largely followed the pattern of the previously published work from these tunnels except that they also put great effort on the development of interferometry for the quantitative study of flow fields. Although the Germans recognized the importance of scale effect, somewhat less effort seems to have been made than in this country to check results in large high-speed tunnels or in flight.





In the development of wings for use at transonic and supersonic speeds, considerable theoretical and experimental work was done on airfoil sections and planforms both in the United States and Germany.

Airfoil section.- Early in the development of low-drag airfoil sections in the United States, it was realized that not only would these sections have low drag at low speeds but would have improved aerodynamic characteristics at high speeds because of lower induced velocities than possessed by conventional sections. Consequently, a family of airfoil sections was finally derived which had satisfactory low drag and considerably improved high-speed characteristics as indicated by low- and high-speed wind-tunnel tests, respectively. Sections such as these were used on two American airplanes, the P-5l and A-26, in operational use in the European war. In Germany some theoretical and experimental work was done in the development of low-drag and high-speed airfoil sections, although the work was not as extensive or systematic as the American development. The German research indicated that some of the older or conventional NACA high-speed sections had fairly satisfactory high-speed characteristics and were apparently content in using them in practically all of their installations. Research in both countries indicated that the Mach number at which large changes in lift, drag, and pitching moment occurred depended not only on the Mach number at which local velocity of sound was first attained but also on the type of pressure distribution. [706] In addition, it was clearly evident in both countries that the conventional airplane was limited to a maximum Mach number of 0.85 to 0.90 because of the loss of lift, rapid rise in drag, and stability and control difficulties at high Mach numbers.

Wing planform.-Late in the war it was recognized in the United States, as a result of theoretical and experimental research, that wing planform had a more pronounced effect on aerodynamic characteristics at high speeds than airfoil section. It was shown by tests at transonic speeds that by decreasing the aspect ratio the compressibility barrier, as evidenced by loss of lift, rapid rise in drag, and large changes in pitching moment, could be delayed to Mach numbers over 0.90. Both theory and experiment at transonic and supersonic speeds indicated that large sweep of the leading edge of a wing (either forward or rearward) would result in delaying and minimizing these compressibility effects to speeds well above the speed of sound. Research in Germany during the war on effects of wing planform was rather extensive and covered a large variety of wing shapes. Near the end of the war in Europe, Germany had an experimental airplane flying with wings designed on the basis of the sweep theory, and practically all of their proposed high-speed airplanes and winged missiles included swept lifting surfaces.

This extensive German research was confined by limitations of wind-tunnel techniques to speeds less than about 90 percent of the speed of sound. Thus, the important transonic region where important changes of aerodynamic characteristics occur was left virtually unexplored by the Germans. Late in the war period the NACA developed techniques to obtain data in this region by means of freely falling bodies and by means of small models mounted in the high-speed flow induced about airplane wings. These unique methods permitted the NACA to obtain data on wings and wing-body configurations continuously through the speed of sound. New wind-tunnel techniques developed by the NACA also permitted data to be obtained very close to the speed of sound. Data obtained by these new methods and by the more recently developed NACA techniques of rocket-powered bodies are laying the foundation of knowledge necessary for the development of airplanes to fly at and above the speed of sound.




At moderate subsonic speeds, the aerodynamic characteristics of bodies of relatively large fineness ratio such as generally used in aircraft fuselages are not critically dependent on body shape, provided that there are no abrupt changes in longitudinal profile. The information generally available at the start of the war was adequate and little further research has been done either in Germany or in America. A great deal of theoretical and experimental research on the effects of modifications to basic body shapes such as cockpit canopies, gun turrets, engine cowlings, and the like has been accomplished by the NACA. As far as is now known, comparable German work was limited to development studies for specific designs.

In the transonic speed range, from 0.8 to 1.2 times sonic speed, the NACA has developed a new testing technique by which the drag of test bodies is determined by dropping them from aircraft at high altitudes. The readings of instruments in the bodies are telemetered to test equipment on the ground. Results of the first of these tests, published in 1945, indicated large variations in flow characteristics near sonic speed and showed that drag reductions can be effected in this speed range by increases in fineness ratio. More recently similar results have been obtained with rocket-powered test bodies. No known fundamental research in this speed range was accomplished in Germany.

At supersonic speeds, body drag varies greatly with shape and fineness ratio. Theoretical studies made by NACA during the war have resulted in the development of methods for calculating the lift, drag, and moment characteristics of slender bodies of [707] revolution with or without air inlets. Supersonic wind-tunnel tests made during the war verified the theoretical results. Original data from systematic wartime investigations of supersonic projectile shapes in Germany and Italy became available to the Committee in 1944. These data were analyzed and published by the NACA. Italian theoretical predictions of the nose profile for minimum drag were verified by these test results. A great deal of supersonic development work on specific projects such as the V-2 missile was accomplished in Germany. However, attempts to obtain fundamental aerodynamic data of general usefulness from these specific projects have been disappointing.

The aerodynamic interference that occurs when two or more aerodynamic bodies, such as wing and fuselage, are combined has been the subject of extensive investigation both in America and in Germany. This problem is of critical importance in the transonic and supersonic speed ranges. No adequate theoretical methods are yet available to aid in the prediction of interference effects in these speed ranges. A large amount of data for specific designs has been obtained in both America and Germany. The German work included several preliminary studies of wing-body interference for swept wings. Similar but more extensive investigations are now under way in America.




Both in this country and in Germany, the importance attached to stability and control investigations is shown by the amount of research performed and the large percentage of test facilities devoted to this work. In order to compare the contributions of the two countries, the subject will be considered under headings based on the flight-speed range concerned.

(a) Stability and Control at Low Speeds or Beyond the Stall.-A large amount of wind-tunnel research has been conducted in both Germany and the United States on special control devices, such as spoilers, intended for use on airplanes equipped with high-lift devices to provide low landing speed. Both countries encountered the same basic problems of control lag and ineffectiveness, and arrived at the same solutions, which consist of suitable spoiler design and location. Flight tests were made in both countries on low-speed research airplanes equipped with special high-lift flaps or boundary-layer control. The problem of adequate lateral control was not completely solved for the airplanes employing boundary-layer control. The results of the research on spoiler controls for use with full-span flaps in the United States were embodied in several service airplanes, whereas in Germany these devices were not generally adopted by the manufacturers.

The spin-recovery problem was studied in both countries by means of free-spinning tests of models in vertical tunnels. Both countries arrived at criteria for use by the designer in providing satisfactory spin recovery.

Stall-warning devices utilizing pressure differences over the airfoil were perfected in both countries.

(b) Stability and Control in the Normal Flight-Speed Range.-An important development made during the war by the NACA was the determination of a set of specifications for satisfactory flying qualities of airplanes. These specifications placed a measurement of stability and control characteristics in flight on a quantitative basis. These specifications were based on complete measurements of the flying qualities of 20 airplanes and were later substantiated by similar measurements on about 30 additional airplanes. These requirements were adopted by the Army and Navy for the purpose of selecting airplanes with desirable stability and control characteristics for combat and service use. A similar set of specifications for desirable handling qualities was prepared in Germany, but these specifications were based on complete tests of only five airplanes and partial tests on a number of others. The German specifications were never adopted as a standard by the German Air Forces but were merely set up as recommendations to guide the designers and manufacturers of military airplanes.

[708] In order to provide satisfactory flying qualities for airplanes in the design stage, procedures were perfected both in the United States and Germany for wind-tunnel testing of powered models of complete airplanes. These tests were generally conducted on all new airplane designs. In addition, theoretical or empirical methods were developed in both countries to calculate the contributions of various parts of the airplane to its stability.

Theoretical work on the dynamic-stability characteristics of aircraft was conducted extensively in both countries. The number of separate investigations conducted in Germany along these lines appears to exceed the number conducted in this country. However, the main factors contributing to dynamic lateral and longitudinal stability were discovered in both countries and the means determined for avoiding troublesome problems, such as control-free oscillations, were the same in both countries. Other problems of dynamic stability encountered in the tactical operation of aircraft, such as the towing of gliders, were thoroughly investigated in both countries.

A solution of the problem of providing desirably light control forces on large and high-speed airplanes was found to be very important by both countries in order that satisfactory military types could be produced. For this reason a large amount of wind-tunnel testing was conducted to develop satisfactory types of control-surface balances. In this country this program amounted to making separate wind-tunnel tests of the control surfaces of practically every airplane that was designed for possible military use, in addition to numerous tests of generalized aircraft components investigated from the standpoint of fundamental research. A similar course appears to have been followed in Germany. In the United States the mass of data accumulated has been summarized and correlated in several summary reports so that it is now available for use by the designer. The correlation of German work does not appear to have progressed to such an extent, probably because of the less centralized organization of their research laboratories.

The development of servo controls both aerodynamic and mechanical types was given increasing emphasis in both countries towards the end of the war. The theory of such devices was well understood in both countries but the German designers appear to have made freer use of these mechanisms in actual service airplanes than did the American designers.

(c) Stability and Control at the Highest Speeds Reached by Conventional Aircraft.-The onset of adverse effects of compressibility on the stability and control characteristics of airplanes was first observed in high-speed dives of fighter-type airplanes. Wind-tunnel and flight tests were conducted in both countries in order to study the reasons for the diving moments and high control forces encountered in these high-speed dives. No satisfactory solution to these problems for service-type airplanes was found by the Germans. In this country, however, dive-recovery flaps were developed which provided a temporary solution. Distortion of the tail surfaces and control surfaces under air loads was found to be partially responsible for many of the difficulties encountered in high-speed dives, and the theory explaining these effects was well developed in both countries. Theories were also worked out to estimate the loss in aileron control due to wing twist at high speeds. The equality of achievement of the United States and Germany in the field of stability and control is shown by the fact that the maximum diving speed reached by aircraft was approximately the same in both cases. This maximum speed was limited by stability and control difficulties rather than by limitations of performance characteristics.

(d) Stability and Control in the Transonic Speed Range.- Investigation of the stability and control of airplanes at transonic speeds became important with the development of jet-propelled aircraft capable of traveling at these speeds. Conventional wind tunnels were found to be unsatisfactory for measuring characteristics of airplanes in this speed range. Considerable stability and control research at high supersonic speeds was [709] conducted by the Germans for application to missiles, but they had failed to develop any means of obtaining information in the important transonic speed range. Two methods were developed by the NACA for conducting tests in the transonic speed range. In one of these methods, known as the wing-flow method, small models are mounted in the high-speed flow above an airplane wing in flight. In the other method freely falling models are dropped from high altitudes and they exceed the speed of sound in falling. Methods for obtaining data from these falling bodies by means of radar and telemeter equipment have been developed in this country. Preparations to build research airplanes capable of flying at transonic speeds were made in both countries at the end of the war. In Germany these airplanes employed sweptback wings which had been shown theoretically to present the possibility of improving stability and control characteristics in the transonic speed range. The beneficial effects of sweepback were discovered at the NACA independently at a later date but not in time to prevent [sic] swepiback wings to be applied to the first research airplane designed for transonic flight.

(e) Stability and Control at Supersonic Speeds.-Stability and control of missiles traveling at supersonic speeds were studied extensively in Germany in several small supersonic wind tunnels. Great emphasis was being placed on the development of many types of supersonic missiles and several large supersonic tunnels were in preliminary operation or under construction at the end of the war. In addition, some missiles designed for supersonic speeds had been constructed and tested. In this country practically no data on stability and control at supersonic speeds had been obtained.


Internal Aerodynamics

The differences in the strategic requirements for American and German aircraft resulted in considerable differences in the types of internal aerodynamic research conducted by the research organizations of the two countries. In the United States, major emphasis was placed on the solution of specific internal-flow problems confronting long-range aircraft powered in most cases by conventional reciprocating engines. An appreciable portion of the research effort of the NACA was allotted to the develop-ment of installations for jet-, turbine-, and rocket-propelled aircraft and to internal-flow systems suitable for transonic and supersonic flight only when it became apparent that the new forms of prime movers could be perfected in time to be useful for the war effort. In Germany, on the other hand, a large percentage of the research effort was allocated throughout the war to the development of jet-propulsion and rocket installations for very fast short-range aircraft and to the development of induction systems suitable for supersonic aircraft and missiles.

Cooling and heat exchangers. The NACA cooling-correlation method was adapted for use with multicylinder aircooled engines during the war years and was further extended to cover the case of the liquid-cooled engine. This method was successfully utilized in the development of the engine installations for numerous military airplanes, thereby substantially shortening the usual troubleshooting development periods. German literature reveals that engine-cooling difficulties continued throughout the war to be one of the principal factors delaying the service use of their new aircraft.

The NACA conducted a number of projects leading to the refinement of aircraft heat exchangers and the evaluation of the factors governing their performance. Comprehensive design charts were developed to aid the cooling-system designer by simplifying selection procedures and permitting the rapid determination of the effects of design compromises on cooling performance. The NACA heat-exchanger research on the whole was confined largely to conventional production-type units. The Germans, however, in addition to similar work, expended considerable effort in the development of tailor-made units for specific airplanes and in research on unconventional arrangements such as the regenerative cooler.




In the decade before the start of the war, the Germans made numerous important contributions to the aerodynamics of compressors and turbines including the development of theoretical methods for calculating the 2-dimensional characteristics of cascades or rows of blades, and the development of cascade testing techniques and methods of correlation of cascade and rotating-machine performance data. During the war, however, their aerodynamic progress appears to have been limited to relatively minor improvements resulting from development work on specific installations. At the close of the war, the aerodynamic design of the German compressors and turbines still closely followed prewar practice. Examination of the mechanical details of German gas turbine engines reveals that important advances were made in construction techniques and production methods. Advances were also made in the development of blade-cooling methods during the war.

Utilizing the cascade testing technique, the NACA has conducted a fundamental, systematic, pressure-distribution investigation of compressor-blade shapes. This work was guided by the general principle that local velocity peaks on the blades should be avoided, in order to minimize friction and separation losses and to delay compressibility effects. This work resulted in design charts from which efficient shapes and opti-mum blade settings can be obtained for a wide range of compressor-design parameters. Low-speed tests of these blades in rotating machines have indicated that important gains in pressure rise per stage and in efficiency can be realized by their use. Theoretical work carried on during the war has recently culminated in a greatly improved method for computing the flow about 2-dimensional cascades of compressor and turbine blades.

Conventional axial-flow compressors are limited to a relative blade Mach number of about 0.8 because of the occurrence of shock losses at higher speeds. It is theoretically desirable, however, to operate at higher speeds in order to produce higher compression ratios. The Germans made two attempts during the war to construct a supersonic axial-flow compressor. The first of these attempts ended in destruction of the machine, and the second produced a very low efficiency and only slightly higher pressure ratio than was obtainable from subsonic compressors. The NACA has been working on supersonic compressors since 1942, starting with stationary tests in supersonic jets in which methods were developed for minimizing the shock losses. Continu-ing this work, a single-stage machine has been designed, constructed, and tested. In its present preliminary stage of development this machine has comparable efficiency, slightly larger mass flow, and a compression ratio four to five times as large as any previous single-stage axial-flow compressor. The knowledge gained from this experi-mental compressor should lead eventually to smaller, lighter, and more powerful turbojet engines.




Both the NACA and German theoretical propeller research during the war period was devoted primarily to development of improved methods of application of the existing theory and relating these applications to design procedures in the form of simplified selection and design charts. In both cases this work eliminated a major portion of the tedious calculations formerly required. The NACA work in this respect was somewhat more complete than the German work in that it included all the important variables in propeller design while the German work did not completely include the effects of design camber and blade width. The German work, on the other hand, was more extensive in the development of theories for the use of shrouds with propellers so that the volume of technical information from the NACA and German work was about the same.

[711] Analytical work in compiling information available from the experimental results and theoretical results bearing on the design of efficient high-speed propellers was carried out more extensively by NACA than by the Germans. The smaller amount of German analytical work is directly traceable to the lack of experimental high-speed research on propellers and propeller-airfoil sections.




During the war no fundamental research was performed by the Germans directed toward the attainment of improved propeller airfoil sections. The Germans used in the design of their propellers NACA 24-series sections, which are considered one step removed in the development of optimum propeller sections. The NACA on the other hand undertook an extensive propeller-airfoil development program which resulted in optimum critical-speed airfoil sections having low drag characteristics (NACA 16-series sections). The development of these airfoils supplied sections for use in propeller design which delayed the onset of compressibility effects to an important extent. The low-drag characteristics of these airfoil sections produced higher propeller efficiency.

Both the NACA and German work included an extensive amount of experimental testing to determine at high speeds the characteristics of airfoils suitable for use in the design of propellers. The volume of technical information was about the same magnitude.




No significant amount of German research on propeller characteristics was per-formed at high speeds during the war period. It appears that the German research effort on propellers was based upon use of available low-speed information to obtain their propeller designs which, when in production, were to be used throughout the remainder of the war without further change. The NACA, on the other hand, in recognition of the advances of high-speed requirements of propellers occasioned by the war efforts initiated an extensive program of high-speed propeller research. This work was directed toward the procurement of information necessary for the design of efficient high-speed propellers suitable for absorbing increased amounts of power. Propeller dynamometers for the Langley 8-foot high-speed tunnel and the Langley 16-foot high-speed tunnel were designed and constructed. At the same time, dynamometer equipment for Flight Research was also developed.

Propellers were obtained from this research which had efficiencies of from 90 to 95 percent through a speed range up to approximately 500 m.p.h. These efficiencies of these propellers are 7 percent greater at low speeds and 22 percent greater at 500 m.p.h. than could be obtained with conventional propellers in extensive use during the war period. The NACA propellers were free from adverse compressibility effects at speeds approximately 100 mph in excess of speeds at which serious effects were encountered with conventional propellers available during the early war period. These conventional propellers had essentially the same performance as the German propel-lers. The adverse effects of compressibility on propellers at high forward speeds were defined in these investigations for the first time. Extensive studies of the effects of propeller shanks on the performance on propellers were made at high speeds and changes in design camber, blade width, and pitch distribution were evaluated.




The German research pioneered the use of sweep in propellers to effect delays in the onset of compressibility effects. These results showed for the first time that the use of sweep in propellers resulted in delays in the onset of the effects of compressibility. However, the best sweptback propellers developed by German research were less [712] efficient, even at high speeds where the adverse compressibility effects occurred, than the high-speed propellers evolved by the NACA research.




Power plant development in Germany during the war period was in general quite comparable with that in the United States, but differed in detail as the result of differences in military situation, thought, and manufacturing conditions. The Germans, envisioning a greater need for high speed than great power or long range, devoted a much greater proportion of their efforts to development of jet and rocket power plants, and correspondingly less to reciprocating engines. As their military situation deteriorated, the development became a frantic effort to obtain performance advantages, and the newer power plants were put into service in the state of incomplete development.

The German philosophy of reciprocating-engine design favored the use of relatively high compression ratio and low supercharger pressure boost, perhaps due to a lack of high-performance superchargers. To engines of this type the shortage of high-octane fuel was an especially serious handicap, which the Germans met to some extent with the adoption of fuel-injection type engines. In the United States, which was ahead of the Germans with turbo- and multi-stage superchargers, engine outputs were greatly increased as a result of fuel and engine research. As a consequence in the field of high-powered reciprocating engines, with which much of the war was fought, German development lagged by approximately a year.

Jet-propulsion research was well under way in the United States at the start of the war, the NACA having conducted full-scale tests of a unit early in 1942. Due to difference in the military situation, jet-power-plant development was not given as much priority here as in Germany, but rapid advances were made. Possession of superior materials gave the United States a marked advantage, and German designs reflected this situation. Military necessity forced Germany to early production of jet engines, whereas the United States, which possessed lighter, more efficient, and more durable units had not swung into large production at the cessation of hostilities.

The turbine-propeller power plant on which the Germans had been working since before the war advanced about equally in both countries, neither of which succeeded in bringing this important type of unit into production.

The intermittent ram jet used to power the buzz-bomb was a German development not matched by similar research in this country. The steady-flow ramjet, or Lorin duct, on the other hand was the subject of basic research by the NACA at the start of the war. However, in Germany ram-jet research was prosecuted with great rigor as contrasted with low priority in this country.

Liquid-fuel and powder rockets for assisting takeoff developed, and in use, here and in Germany were strikingly similar in design and principle, although there were differences in propellant preferences. Design of rocket-propeller airplanes, started in Germany before the war, resulted in the ME-163, capable of phenomenal speed but so limited in range that it was not regarded by the Germans themselves as especially practical. It was in the field of long-range rocket missiles that the Germans made the most progress. Although the United States had by no means neglected rocket development in its application as a power plant for long-range missiles, the Germans had investigated and overcome many of the practical problems, and several important types had been brought into production.

Viewed as a whole, Germany contributed most in the development of long-duration high-powered liquid-fuel rocket and the ram jet, whereas the United States made greater advances in power, reliability, and weight reduction of reciprocating power plants. In jet and turbine engines, developments were about equal, with Germany getting into production earlier, but with the United States leading in power, weight reduction, reliability, and economy.




At the ending of the War, the Germans had successfully developed and operated subsonic ground-to-ground missiles, the V-1. They had also successfully developed several subsonic ground-to-air, air-to-ground, and air-to-air missiles but had insufficient time to get them into action. They had developed also a wingless supersonic artillery-type missile, the V-2. In addition to these accomplishments, intensive research was under way on stability, guidance, and aerodynamic problems of supersonic interceptortype missiles.

At the corresponding time in America, although guided missiles presented a significant picture from the military viewpoint, most of the research effort had been directed toward providing superior inhabited aircraft with increasing but still small expenditure of effort on the guided missile. Because of this difference in emphasis, no strict comparison between American and German missile research can be drawn. In the fields such as high-speed aerodynamics, automatic control and stability, and launching, comparison can be made even though progress on the latter two items was not essential to victory.

Aerodynamic research was pursued with the utmost vigor in Germany and America throughout the war since it is the basis for air supremacy in both the missile and aircraft operations. Work in Germany emphasized the use of numerous supersonic wind tunnels, while in America high subsonic tunnels were pushed to a high state of refinement. In addition, in America flight methods were devised for extending aerodynamic information through the transonic speed range (speeds from about 700 to 1000 miles per hour) where the inherent physical restrictions of wind tunnels prevent their use. The Germans had devised no means for aerodynamic research in this transonic speed range, a fact which is now realized would have greatly inhibited their further progress with winged missiles and man-carrying aircraft as well. Work in the German supersonic tunnels was devoted largely to reduction of drag, problems of high moment changes, center of pressure shift, lift and control effectiveness, and damping derivatives in roll, pitch, and yaw. This work was in the category of initial exploratory work and showed some of the difficulties which had to be overcome but offered few of the solutions to these difficulties. The benefits of sweepback were discovered several years earlier in Germany than in America but, by the end of the war, American information on sweptback configurations was equal to and, in the transonic range, surpassed that possessed in Germany. Neither country, however, had successfully used sweptback wings to increase aircraft or missile speeds in actual operations.

American work on automatic stability was done largely in conjunction with Army and Navy glide bombs and with controlled bombs such as the Azon and Razon. This work proceeded on a sound theoretical basis so that corrective measures for difficulties observed in flight tests were quickly applied.

Automatic stability and control theory was also sufficiently advanced to permit quick adjustment of the American version of the German V-1 and, in the closing months of the war, U.S. Army tactical trials of this weapon showed performance surpassing that achieved by the Germans although the military and naval situation did not require its use. Similarly, a zero-ramp launching technique was devised for V-l missiles which would permit mobile launching stations in contrast to the massive steam ramps used for the German operations.



39. "Report of the Director of Aeronautical Research submitted to the National Advisory Committee for Aeronautics at its annual meeting, October 23, 1947."


[Hugh L. Dryden succeeded George Lewis as Director of Aeronautical Research in September 1947. In this, his first formal report to the Main Committee, he outlined his [714] goals and impressions. The subtle changes he introduced would lead to a more rational functioning of the overall NACA research program through increased utilization of the technical committees, greater emphasis on basic research, and faster dissemination of research results to meet the needs of industry.]


I have the honor to submit herewith my first report to the Committee as Director of Aeronautical Research. In the seven weeks that I have served you in this capacity, I have made a beginning in the large task of becoming familiar with the activities under way at the three laboratories. I have made courtesy calls at the plants of a few aircraft manufacturers, and I have taken part in the Budget Bureau hearings on our estimates for the coming fiscal year. The next few months will continue to be a period of education for me. I consider myself very fortunate to have the benefit of guidance from Dr. Lewis, and I am happy to say that the entire staff has given me its wholehearted support and cooperation. The Associate Director, Mr. Crowley, and the Executive Secretary, Mr. Victory, have not only been ready to give me background information and express their views on the problems arising from day to day, but they have also kindly relieved me of much administrative routine.

One of the first tasks which I have set for the staff and myself is a better formulation of the Committee's research programs. The principal tool at present for recording and keeping track of the research programs is the research authorization, of which there are hundreds, and the job orders, of which there are thousands. The usual lists of investigations requested by the military services, and of the contracts with educational institutions approved since the last meeting, have been distributed to you. These serve the useful purpose of enabling one to trace the history of a particular task, but are not useful instruments for the control of general research policy which I consider to be the function of the Main Committee and the standing technical committees. I believe that our research programs must be formulated and examined from various points of view and studied in the light of their environment, i.e., the international situation, the current state and objectives of aeronautical development, and developments in basic scientific research in physics, chemistry, and engineering.

At this stage in my study I can only illustrate by specific examples what I have in mind. The urgency of aeronautical research results from the relation of air power to national security. Aircraft having the highest speed dominate the air. The development of the turbo-jet engine during the last war made available a large amount of power in a small package, and thus paved the way for the attainment of much higher flight speeds than possible with reciprocating engines and propellers. It is clear that there is no upper limit to the possible speed of aircraft. The nation that makes the best research effort to develop the new power plants and explore the problems of high-speed flight can lead the world in air power. That nation must be the United States.

In this environment one of the objectives of present-day aeronautical development is the attainment of horizonal flight of a piloted aircraft propelled at supersonic speeds for long distances. It is the duty of the NACA to provide for the military services and the industry, the basic data on aerodynamics and propulsion to make piloted supersonic flight, not only possible, but safe and reliable. A large part of the Committee's research effort is directed toward this objective. The apex of this effort is the flight research on high-speed research airplanes at Muroc, California, conducted by the military services, the aircraft industry, and the NACA in cooperation. This type of organized effort has been extremely successful and valuable, so much so that the headquarters staff and I are studying the possibility of a similar procedure for expediting and focusing research effort on power plants of the future. It is gratifying that the flight tests have as yet shown nothing which was not predicted from wind-tunnel, wing-flow, and rocket tests of models.

[715] Another large segment of the Committee's work relates to the transport airplanes of today and the near future, in particular, to their general handling characteristics and flying qualities, their comfort and safety in normal flight, in flight in rough air, and in emergency landings on land and sea.

Other work is applicable to all aircraft, to improve their performance, and to study the application to them of improved wing sections, controls and of such new developments as boundary-layer suction.

For budget and accounting purposes work under such general objectives is broken down into 19 research programs relating broadly to research on the airplane itself, to its power plant, and to operating problems. Programs in transonic and supersonic aerodynamics, stability and control, and loads, began about 1944, and have grown to a considerable magnitude, accounting for the fact that our budget estimates are higher now than during the war years. Since supersonic aircraft must also operate safely at subsonic speeds, and since they require new wing sections and wing plan forms, a large fraction of the subsonic work conducted at present is devoted to supersonic aircraft.

A typical large area of work in this field is on wing plan forms. From theoretical considerations and limited experimental data, three general types of plan forms have advantages in various high speed ranges. These are the sweptback and sweptforward, the low-aspect-ratio, and the triangular. The general objective of the NACA work in this area is to determine the properties of these plan forms over a wide range of Reynolds and Mach numbers so that the designer may have the basic data from which to make the best choice for a particular design intended to accomplish a specific purpose.

One segment of this area of work is that relating to a specific triangular plan form selected in the light of present theory as best for a specific design Mach number.

The power-plant work in 1944 was mainly on reciprocating engines, whereas today the work is largely on jet engines. Considered in relation to the major goal of the supersonic flight of piloted aircraft, the NACA program of flight-propulsion research breaks down into the major divisions of turbo-jet and turbo-prop, rocket, and ramjet. In each of these divisions there is a two-fold goal-(1) to obtain increased performance for a given size and weight, and (2) to increase the reliability and life. These goals are ever-receding ones as development progresses, but there are certain landmarks, for example, the fuel economy of reciprocating engines, which research workers believe will ultimately be obtained with turbo-jet engines.

Let us consider the program for turbo-jet engines in greater detail. To increase the performance of the complete power plant for a given size and weight, the same goal must be set for each of the components, i.e., compressor, combustor, turbine, bearings; the components must be matched to secure the optimum performance of all components under the same conditions; and the operating variables must be suitably controlled. Considering a single component, the turbine, specific avenues of research are open including aerodynamic improvement of the blade design, and operation at higher gas temperatures either through cooling of the blades and rim or through the use of materials capable of withstanding higher temperatures such as improved metal alloys, ceramics, or mixtures of the two. The solution of these problems rests on basic research in aerodynamics, heat transfer, engineering mechanics, properties of materials, etc.

In a similar manner the goal of increased reliability and life leads to studies of blade stresses, vibration and flutter, disc failures, and icing protection.

Having broken the program down into specific problems (research authorizations or job orders) to be attacked by individuals or small groups, it is necessary to integrate the results and study their application by research on complete power plants. It has been the policy of the Committee to do such research on power plants under development by the armed forces and industry, and intended for large-scale procurement. In [716] this way there is great incidental benefit in securing early application of the research results. However, designers must be somewhat conservative in the development of such power plants because the armed services must secure tactically useful power plants.

In addition to this type of breakdown of the research programs stemming from the practical goals, there is need for another which begins with the state of knowledge in the basic sciences. Such work lays the foundation for the future and opens the way to more rapid accomplishment of the detailed tasks arising from our general objectives. The Committee has already taken steps in its estimates to provide facilities for basic research in the field of extremely high altitudes and high speeds, and already has under way many specific research tasks arising from this type of breakdown of the research program.

It is quite obvious that the ramifications of an adequate research program are so great that no single individual can master or guide the details. The technical staff of the Washington Office has been increased, and we have asked for a further increase in the 1949 Budget. I believe that it is your function to determine the general policy as to the objectives of research in relation to aeronautical development and air policy. Through the standing technical committees, the technical goals in specific fields are reviewed in the light of general objectives, and recommendations made to you. The programs for particular areas within these technical fields are then reviewed in detail by the subcommittees of our standing committees. The programs as approved by the Main Committee are carried out by the Director of Aeronautical Research and his staff.

In my conversations with the top officials of aircraft companies, great stress was laid on the need for the prompt dissemination of information, and the Committee was complimented for improvement in this respect. I believe that the groundwork has been laid for still further improvement. The establishment of an index system for all reports, the publication of abstract cards with the reports, and the use of the memorandum report make the results more promptly available and more useful. The best means of rapid transmission of information so far found is the technical conference of relatively small groups of experts in a relatively narrow field. Many more of them will be held. The next one scheduled is that to be held at the Ames Laboratory on November 5 and 6 to inform the designers of military aircraft of the latest information of use in the design of transonic airplanes.

There are many other matters of general policy to which I have given some thought and which I will discuss with you from time to time. I have been asked to express my personal views with regard to aeronautical research and government policy before the President's Air Policy Commission. Copies of my statement have been distributed to you. They should be kept confidential until released by the Commission.


* Deutsche Versuchsanstalt fur Luftfahrt (German Aeronautical Research Establishment)

** Civil Aeronautics Administration.

*** Unidentified; probably a jocular reference to Pratt and Whitney Aircraft Company

**** Robert E. Gross, president, Lockheed Aircraft Corporation

***** The Cyclone 18, a Wright Aeronautical Corporation 18-cylinder 2200-hp engine used on the B-29 bomber

****** Sir Bennett Melville Jones, chairman, Aeronautical Research Council

# Minister of Aircraft Production

## Civil Aeronautics Administration

### Donald W. Douglas, president, Douglas Aircraft Corporation; Eugene E. Wilson, president, United Aircraft Corporation; Robert E. Gross, president, Lockheed Aircraft Corporation

#### Col. Carl F. Greene, U.S. Army Air Forces, liaison officer, Langley Laboratory.

##### Hermann Theodore Schlicting, director of the Institute of Fluid Mechanics, Technical Institute of Braunschweig.

###### Jacob Ackert, Federal Technical Institute, Zurich

####### N E. Joukowski, professor of mathematics, University of Moscow, author of a classic theory of lift