[xxvii] On the most superficial level the title of this book refers to the officer who first headed Langley Aeronautical Laboratory, the original and, until 1941, the only research center of the National Advisory Committee for Aeronautics. In all of NACA history-1915 to 1958-there were only two such officers: Leigh M. Griffith (b. 1882, d. 1940) and Henry J. E. Reid (b. 1895, d. 1968). Griffith served as engineer-in-charge from 1923, when NACA headquarters created the position, through 1925; Reid succeeded Griffith in 1926, filling the top position at the lab until his retirement from the National Aeronautics and Space Administration (NASA)* in 1960.
For the last twelve years of his career, however, Reid managed Langley not as the engineer-in-charge but as the "director." In 1948 the NACA changed his twenty-two-year-old title in anticipation of Public Law 167 (passed 13 July 1949, 81st Congress, first session). This law authorized the chairman of the NACA to create "ten positions in the professional and scientific service" of the federal government, "each such position being established in order to enable the NACA to secure and retain the services of specially qualified personnel necessary in the discharge of the duties of the Committee to supervise and direct the scientific study of the problems of flight with a view to their practical solution."1 Before this time Reid's salary as engineer-in-charge was boxed in below $9,000 per annum by civil service criteria which discriminated against engineers in favor of scientists. The decision in 1948 to change Reid's title to director was thus part of a larger NACA scheme to increase annual pay to its top executives, and enhance their social and professional status, by giving them academic-sounding titles like those borne by individuals in the higher grades of the federal bureaucracy. As Vannevar Bush, chairman of the NACA from 1939 to 1941, had once said, a scientist may sell a bill of goods to Congress when an engineer could not get a street car token on Capitol Hill. 2
Despite the increased pay, Reid was privately reluctant to have his official identity changed after so many years. Like Griffith before him, he was [xxviii] an engineer and proud of it. He had earned a bachelor's degree in electrical engineering nearly half a century before at Worcester Polytechnic Institute in Massachusetts, and much of his work, both before and after becoming Langley's engineer-in-charge in 1926, truly classified as engineering. To have worked in the field of aeronautics in the 1920s and 1930s was to have been a participant in what was indisputably one of the greatest and most rapidly successful engineering adventures in all history. Born into a world without flying machines, his generation had known the airplane at a time when it barely worked, yet lived to see it perform wonders. These achievements, Reid believed, had been largely the result of practical engineering solutions to the outstanding scientific and technical problems of flight. Congress had created the NACA in 1915 "to supervise and direct the scientific study of the problems of flight with a view to their practical solution." But in practice at Langley, the keystone of the organization's charter had rested chiefly in the end of that phrase, "with a view to their practical solution." This meant that aeronautics had been treated not so much as a scientific discipline, but as an area for engineering research and development. Most Americans did not know how significantly the NACA laboratory of which Reid had been in charge had contributed, and was continuing to contribute, to solutions of this sort; most Americans did not even know that the NACA existed. This anonymity frustrated Reid occasionally-though he knew it had certain political advantages. However irritating it had been to hear the unknowing public frequently giving scientists all the credit for accomplishments he felt rightfully belonged to engineers, the irritation never prompted him to question his organization, profession, or identity as the engineer-in-charge.
Neither Reid nor anyone else who knew anything about Langley ever doubted that at nearly all levels of laboratory research activity, not just at the top, it was the engineer who was in charge. Novelist James Michener picked up on this fact in the late 1970s during interviews with veteran NACA employees. In his book Space, Michener has a crusty, white-haired wind tunnel jockey scolding a new employee for crediting a scientist with the design of the 16-Foot High-Speed Tunnel: "Scientists are men who dream about doing things," he reprimanded the young man. "Engineers do them. This [tunnel] was designed by engineers, built by engineers, and is run by engineers. You're an engineer, young fellow, and you're to be proud of it."3 Wind tunnels and other test equipment-which required engineering talents for design, development, operation, and exploitation formed the laboratory's backbone. By the end of the 1930s, fifteen of the eighteen aerodynamics sections at Langley were named after wind tunnels or other specific experimental setups. The only parts of the lab with names suggesting a theoretical approach to research were the Mathematical,...
....Flutter and Vibration, and Propeller Sound and Noise research sections, all of which belonged to the small and somewhat isolated Physical Research Division.
Langley's penchant for experimental programs was in fact very appropriate for the actual state of aeronautics in the period 1915 to 1930, the years when the NACA developed its own operating style. To a considerable degree, the empirical approach for which the agency became well known seems to have been dictated by the nature of the aircraft design problems confronting the laboratory after World War I and by the inadequacies of theory in addressing them.
The generation of airplane designers responsible for some of the most famous World War I aircraft had used an intuitive, daring empirical engineering loosely connected at best with any theory of aerodynamics or structural integrity. Geoffrey de Havilland (1882-1965), Anthony Fokker (1896-1939), and Gianni Caproni (1886-1957), among others, produced stable and maneuverable airplanes using essentially a job-shop approach. The British designer Thomas Sopwith (b. 1888) never put his early planes through a single stress test. One of his prototypes could be designed, constructed from full-size chalk drawings on the factory floor, and test flown in less than three months.
During the 1920s frail wooden biplanes covered with fabric, braced by wires, powered by heavy water-cooled engines, and driven by hand-carved wooden propellers still ruled the airways. This meant that very large gains in aerodynamic efficiency- perhaps even the biggest payoffs then possible- would follow almost immediately once the aviation establishment possessed correct answers to just a few questions, such as:
Can drag be reduced without degrading cooling? If so, how?
How can wings be shaped to increase lift at low speeds and decrease drag at high speeds?
How and when do flaps work best?
How can effectiveness and control force be accurately predicted for ailerons, elevators, and rudders?
Is it worthwhile to retract landing gear?
In essence, each of these questions was asked as a result of someone's practical concern and thereby fell into the category of applied fundamental research. For the most certain progress toward practical solutions, engineering talents were required, along with wind tunnels and other sophisticated experimental equipment which, at the time, only the federal government could afford. Because it was staffed and managed mainly by engineers and experienced an early proliferation of large and unique test facilities, like the Variable-Density, Propeller Research, and Full-Scale wind tunnels, Langley laboratory was admirably suited to handle the technological problems at hand.
On the other hand, the professional disposition of the Langley staff might have assured the victory of empirical approaches regardless of the nature of the aeronautical research problems of the day. George Lewis, the director of research for the NACA in Washington from 1919 to 1947, was, like Griffith and Reid, also an engineer. Though he respected theoreticians and employed a few at Langley, Lewis wanted "his boys" at the lab to look for practical solutions. It should come as no surprise that a laboratory in which engineers prevailed formulated problems in a way that required for their solution just those methods, techniques, and apparatuses in which the engineer himself was especially skilled.
In a famous paper on wing section theory published by the NACA in 1931, Langley physicist Theodore Theodorsen suggested that the laboratory staff sometimes tied the progress of their work so completely to the use of test equipment that the equipment started to use them.4 For example, while possession of the world's first full-scale propeller research tunnel presented Langley in 1926 with a unique opportunity to explore systematically the potential of dozens of different cowling shapes and arrangements, having this large and costly research plant also obligated the lab's researchers to make full and routine use of the facility.
The symbiosis between engineer and wind tunnel would grow so strong over the years that it was often almost impossible for management to put a machine out of business. The closing of some tunnels that had reached the point of diminishing returns- like the Propeller Research Tunnel in the 1940s- was accomplished only by overpowering stubborn defenders. Sometimes even after equipment was formally abandoned, old operators tried surreptitiously to run tests with it. Demolition proved the only sure way to end a tunnel's life.
Whether it was the professional disposition of the staff or the nature of the aircraft design problems then confronting it that gave the NACA laboratory its strongest dose of empirical flavoring, engineering was what NACA Langley was all about. Once by the late 1920s it had settled into its niche in the American aeronautics community, it never really intended to do anything else. Langley did little "basic" or "scientific" research in the usually accepted senses of those words; rather, almost every investigation [xxxiii] done there, whether "fundamental" or "developmental," aimed at a useful aircraft application.5
Though empiricism clearly predominated at the laboratory, a careful study of Langley history also shows that some NACA researchers were more than willing and more than able to resort to theoretical analyses when necessary. Demonstration of this should lead to revision of some current historical interpretations of the NACA, such as the one expressed by Edward Constant II in The Origins of the Turbojet Revolution. Professor Constant argued in one chapter of this deservedly prizewinning and influential book that the NACA performed "first-rate empirical work" but accomplished "minor work, or no work at all, on fundamental theory." His interpretation, partly accurate only if one uses a strict construction of the term "fundamental," implied that the NACA accomplished its empirical work without the help of any theory, an oversimplification which the history of several Langley programs- most notably the development of laminar-flow airfoils in the late 1930s (see chapter 4) and of slotted-throat transonic tunnels in the late 1940s and early 1950s (see chapter 11)- shows to be misleading, if not wholly incorrect. The NACA might have been "widely recognized for the excellence of its experimental data and for little else," as Constant stated, but this recognition was based on a popular misunderstanding of the subtle but often necessary interplay between theory, experiment, and design in successful engineering science.6 In any case, the "little else" had its profound effects upon aviation.6
The unwritten rule for the work of any engineer is to bring everything to bear on solving the problem of the moment. This means bending every effort, be it cut-and-try, experimental, theoretical, or any combination of the three. The bias of an engineer against theory is not that of the philosophic doctrinaire; the engineer simply knows from his working experience that theory has its limitations, that there are too many things in life that draw one aside from the charm of a theory, and that facts often murder a theory. Nonetheless all of the better engineers at Langley ultimately realized that they needed some solid theoretical ability- because one never knew when it might be essential. They understood more and more, especially as the time arrived when flow velocities over parts of aircraft approached the.sonic regime, that aerodynamic refinement could not go on endlessly on a purely empirical basis. Without some constant theoretical guidance, they would seek answers to too many ill-conceived and unnecessary questions. Motivated by an awareness of this potential danger, several Langley engineers worked hard from the mid-1930s to master such subjects as applied mathematics. This mastery enabled them to make some notable theoretical contributions and to provide valuable consultation to [xxxiv] the rest of the staff. Consequently, the theoretical analysis necessary for lifting an experimental series beyond the occasional impasse was usually accomplished in-house.
To say that the NACA employed some researchers with excellent theoretical capabilities is not necessarily to say that it had a sufficient supply of them. Theoretical aerodynamicists were hard to find in the United States. American aeronautical programs by and large produced engineers of the practical sort described earlier. Stanford University's aerodynamics professor Elliott G. Reid, who worked at Langley from 1922 to 1927, complained in the preface to his 1932 textbook on Applied Wing Theory that "the average graduate of an American technical school cannot be expected to be very familiar with fluid mechanics, to have a working knowledge of potential theory, or to have facility in the use of either the complex variable or Fourier series" because neither the teachers nor the textbooks were there to instruct about such advanced information or problem-solving methodologies.7 If more crackerjack theoretical aerodynamicists had been available, the NACA would have hired them. But to hire people and call them theoreticians when they were not really very good at theory would have served no useful purpose. Thus the most influential theoreticians at Langley before World War II were Max Munk and Theodorsen, two accomplished European imports, and the most influential theoretician at Langley after the war was Adolf Busemann, the accomplished German aerodynamicist who had fathered the swept-wing concept.
Without a doubt, the NACA could have benefited from more theoretical capabilities. But it is equally true to say that the NACA could have benefited from more experimental capabilities. The problem for management besides acquiring a sufficient number of talented experimentalists and theoreticians was motivating the two types of researchers to work together productively. I. Edward Garrick (1910-1981), a talented mathematician who worked closely with Theodorsen in the 1930s and 1940s, believed in retrospect that NACA management might have stimulated a more gainful exchange between theory and experiment if fewer researchers had been organized around use of any given experimental facility. If not for this clustering around equipment, Garrick suggested, theory might have come to the aid of experimentation more quickly and less accidentally than it typically did.8 One can thus wonder, as some veteran Langley researchers now do, whether the NACA might have improved its total performance by forcing direct interaction between different types of research sections more often, no matter how this might have upset those temperamental individuals who headed them. One can also wonder whether the NACA might have achieved more by fostering a few small groups of imaginative individuals possessing....
.....both inventive engineering skills and creative theoretical talents, and then encouraging these groups to consider the possibilities lying beyond contemporary technology.
The title of this book suggests a final meaning. Despite the influence of economic, political, and military objectives over NACA programs, Langley engineers enjoyed considerable freedom to advance research as they, not others, wanted. To a great extent, then, they were themselves "in charge" of what they did and how they did it. In this respect one may compare the position of a Langley engineer to that of an architect. Though "dependent upon commissions from patrons for the opportunity to work out his ideas," an architect "can usually design a building which reflects his personal artistic ideals and intentions as well as serving the client's needs."9 The best architects are also great artists, and so also are the best engineers. It is thus important to address not only the bureaucratic circumstances in which Langley engineers worked, but also the engineers' personal drives and intentions. As historian Arnold Pacey wrote in The Maze of Ingenuity: Ideas and Idealism in the Development of Technology:
[xxxvi] We just may find that what excited Langley engineers most of all was the spirit of adventure and exploration.
Engineer in Charge is basically a technical analysis of NACA history from the perspective of Langley laboratory to complement Alex Roland's headquarters-centered institutional study, Model Research. I first read Roland's manuscript in October 1980; this was six months after he completed the first draft of his book and eight months before I would spend my first day under NASA contract researching Langley history. Quite naturally, his scholarship guided my endeavor greatly. But Engineer in Charge will hopefully do more for the reader than gloss Roland's previous work. From the beginning, I tried to move the analysis of NACA history in entirely different directions and to offer new ways of looking at some of the same things. By this I certainly do not mean to say that my intention was to build a rival interpretation between which readers of the two books could choose. Rather, my purpose was to add another dimension to Roland's overall story.
Neither was it my idea to recite in detail all of Langley's technical achievements. There were too many research programs, major and minor, conducted at the lab over too many years for that end to be achieved, even if I had thought it desirable. Instead, my plan was to explore the histories of (1) the most technologically significant research programs associated with the lab, and (2) those programs that, after preliminary research, seemed best to illustrate how the lab was organized, how it worked, and how it cooperated with industry and the military.
In looking back over this book, I can see how informed readers might think that my approach resulted in a somewhat positive distortion of the Langley record. Citing my emphasis on the most technologically significant research- i.e., programs that led to the low-drag cowling, laminar-flow airfoils, wartime drag reduction, supersonic flight, transonic tunnels, the area rule concept, and spaceflight- they might argue that little if any room was left for the many draws and defeats of NACA research (like the NACA Langley "failure" in early jet propulsion research, the subject of chapter 8). They might wonder whether the projects whose histories I have presented are just those that Langley veterans trotted out before me to demonstrate how good they were.
I acknowledge these concerns. Nevertheless I stand by the approach I have taken, for I believe it has led to the most useful understanding of Langley. After some months of preliminary research and oral interviewing, I discovered that there was much more to the supposedly well known projects [xxxvii] than what had been published in contemporary newspaper and magazine stories or in George W. Gray's book Frontiers of Flight: The Story of NACA Research (New York: Alfred A. Knopf, 1948). And what was known was often misleading. More astonishingly, I found remarkably little agreement even among NACA veterans over how these projects had come about, how they had been conducted and managed, and what they ultimately signified. Moreover, previous historical treatments of these projects (with the exceptions of Roland's book and Richard Hallion's Supersonic Flight: The Story of the Bell X-1 and Douglas D-558 [The MacMillan Co., 1972]) had not benefited from significant research in Langley's correspondence and research authorization files.
I thus felt the need to clarify important episodes in Langley history that have been imperfectly apprehended, not only to document these episodes more completely but also to put them together, as had never been done before, in the context of an overall thesis- that of engineer-in-charge. I considered examination of outstanding research programs not only a way of giving credit where credit was due, but also a means for institutional and technological case study. This dual function could only be accomplished, however, if the outstanding programs were demythologized and understood, not for what the NACA's publicists said they were, but for what they were in fact.
My intent was not hagiographic; I did not mean to tell a story of heroic engineers and their triumphant research. Nonetheless my book has strong central characters- George Lewis, Max Munk, Henry Reid, Eastman Jacobs, Theodore Theodorsen, John Stack, Robert T. Jones, Robert R. Gilruth, Richard T. Whitcomb, John V. Becker, and Floyd L. Thompson, to name some of the more prominent. I made a real effort to bring these personalities to life. Those men who are deceased I came to know by reading their correspondence and transcripts of interviews made with them while they were alive, and by listening to what friends, colleagues, and even some rivals had to say about them. Most of those still living I was able to meet or at least talk to over the telephone.
By thinking about all of them as the kind of people one might meet and know, naturally I began to like some more than others. My preferences no doubt show up- I liked Max Munk in spite of what I learned about him- but after hearing from NACA veterans who have read the book in manuscript, I believe that the portraits are fair overall. In any case, I doubt that the reader will find any of the portraits "heroic." In fact, my depiction of Stack is somewhat iconoclastic.
Readers should also be aware that my account of Langley's past is what historians of science call internal history. I tell Langley's inside story and [xxxviii] do it largely from Langley's own documents. The object is to illuminate the meaning of those often obscure day-to-day in-house practices, procedures, and technical demands that determine so much of the life of any research laboratory. And I also tend to emphasize the laboratory's local rather than its national or international setting. Instead of comparing and contrasting Langley's experiences with those of other research institutions, such as the Naval Research Laboratory or the Bell labs in this country or the National Physical Laboratory in Great Britain, I stay more "at home" to see how the personality of the NACA's oldest laboratory evolved within its own setting in Tidewater Virginia.11
This approach has obvious drawbacks. For one thing, it tends to overly parochialize the history. If my object had been to make a complete evaluation of the NACA- what the military, industry, and general public, in both the United States and Europe, thought about the agency's overall research record- then my local focus on Langley might have detracted greatly from my study. Obviously I would have had to give far greater credence, as did Roland, to what outsiders thought of, and how they influenced, Langley. But in any case I trust that the reader will not think I have treated the laboratory as a closed system. The book does analyze Langley's relations with NACA headquarters, the other NACA laboratories that were eventually created, and the NACA's clients, even if not as completely or as theoretically as some readers might prefer.
The manner of my written presentation may not suit all readers, for it is something of a hybrid. Those who do not know the fundamental principles of flight may find parts too technical for their liking; experts in aerodynamics will no doubt find many of my technical explanations simplistic or inadequate. Wanting both the. layman and the aeronautical engineer to enjoy my book, I tried to steer a middle course.
Finally, in a book whose theme is the engineer in charge, there should be plenty of pictures to stimulate the mind's eye, a vital organ for creating, understanding, and retaining technology. There are around 300 photographs in this book, an uncommonly high number for what is meant to be a scholarly publication. But I believe, as Mark Twain once wrote: "Dates are hard to remember because they consist of figures; figures are monotonously unstriking in appearance, and they don't take hold, they form no pictures, and so they give the eye no chance to help." For Twain, likewise for me and the Langley engineers I know best, pictures are the thing.
* Usage varies on the pronunciation of the names NACA and NASA. In this book, NACA's meant to read as four individual letters ("the N-A-C-A"), while the acronym NASA reads as a two-syllable word.