[61] The research work performed by the NACA at Langley had experienced a slow but steady growth from its start in 1920 to the time I arrived at the center in 1940. The number of personnel had increased from 15 to 739. The research facilities included several wind tunnels and the Flight Research Hangar, which were most all located in the East Area, a section of Langley Field on the side closest to the center of Hampton. I had only a relatively short period of employment before war was declared following the bombing of Pearl Harbor on December 7, 1941. As a result of the war, the aviation industry in the United States experienced a period of phenomenal growth and the research activities at Langley were similarly expanded. The number of professionals at Langley increased from 277 in 1940 to 1158 in 1950, and the total number of employees increased from 739 to 3388. Two new NACA research centers, the Ames Aeronautical Laboratory in Mountain View, California, and the Lewis Laboratory in Cleveland, Ohio, were established just before the war and were managed by personnel transferred from Langley. The war naturally had a major effect on the scope of the work conducted. New technical developments such as the jet engine and the capability of flight at supersonic speeds required many new research facilities and created new technical fields of interest. The administration of the center, however, and the environment for research continued on a surprisingly even keel, probably because the same director and many top management personnel continued in their positions throughout this period. A brief summary of some of the effects of the war on my work in the Flight Research Division is presented in this chapter.
Effect of the War on Living and Working Conditions
When I came to Langley in July 1940, I entered into what seemed like an ideal environment from the standpoints both of living and working. I have described these conditions in more detail in a journal article (ref. 3.1). This was my first experience living away from home and free from the rather rigorous program of studies at MIT. I enjoyed the opportunities for social life, the friendliness of the local people, and the many recreational activities. The model airplane club, with members that included many expert model builders who had been hired by the Langley management from all over the country as technicians and model builders in the shops, gave me an opportunity to meet new people and to continue my hobby of model building and flying.
[62] At the NACA hangar where I worked, some evidence of military buildup was evident. Gilruth had already run flying qualities tests on some of the new military airplanes, such as the Seversky P-35 pursuit plane, the Boeing B- 15 and B- 17 bombers, and the Vought F4U-I Corsair Navy fighter. There were still many active projects directed at private and commercial flying. About five light planes, including those built by Piper, Taylorcraft, Stinson, and Bellanca were undergoing tests, and Gilruth had modified a Piper Cub to make it stall- and spin-proof. Ongoing programs were being conducted by the Aircraft Loads Section to make routine measurements of gust loads on airplanes in commercial operations, and the first pressurized commercial transport, the Lockheed C-35, was used to explore turbulence at high altitudes in thunderstorms.
The impact of the war hit suddenly with Pearl Harbor. Hangars were camouflaged and blacked out. For a month or so after the declaration of war, Langley engineers were assigned to guard duty at night in the research facilities to warn of possible terrorist attacks. When I was on this duty, I tried to do a lot of report writing, but I found that the reports written in the loneliness of night tended to be rather rambling and usually required rewriting by the light of day. Soon, regular security guards were hired and engineers were relieved of this responsibility.
The war inhibited social life for two reasons. First, the work week was increased from 44 hours to 48 hours. With work all day Saturdays, there was not much time even for necessary shopping. Also, gas rationing was in effect, which prevented any trips except in the local area. Everyone at Langley worked very hard during the war. This was a period of rapid expansion in which new engineers were hired from engineering schools all over the country. Many of the NACA engineers were sent on recruiting trips, but I did not receive this kind of assignment. Later, starting in 1943, I taught courses to many of the new employees in the subjects of stability and control and handling qualities. These courses, under sponsorship of the University of Virginia, were given at night at Hampton High School. Preparation of lectures for these courses was a burden on me because I am not a fluent speaker and had to know the course material in detail before I could present satisfactory lectures on it.
One source of concern during the war was induction into the armed services. Some of the Langley employees, of course, felt compelled by patriotism to join the military services. Others had a hard time convincing their local draft boards that aeronautical research work was of sufficient military value to merit deferment. Eventually, the NACA management in Washington, under pressure from the industry to maintain the research and development capabilities at the NACA laboratories, obtained approval from Congress for a plan in which all employees doing essential work at the center would be inducted into the Army then immediately returned to their jobs at the center in civilian status. The details of this arrangement are described more fully in the book Engineer in Charge, a history of Langley by Dr. James Hansen (ref. 1.1). I was affected by this plan by having to go up to Richmond for my induction physical, but then immediately returned to my regular work.
Some Effects of the War on Research Activities
Prior to the war, Langley had close relations with the military services through membership on the main committee of the NACA of high-ranking military officials. The projects done by Gilruth on handling qualities, as well as studies by other sections of the Flight Research Division on loads and performance, were strongly appreciated by the military services. As a result, an arrangement was made to supply the NACA with the third airplane off the production line (later changed to the fifth) of every new military airplane produced. This rule was followed for many years. In view of the large number [63] of new military airplanes produced during the war years, this rule supplied Langley and the other NACA centers with an excellent opportunity to contribute to the war effort by recommending improvements as well as by doing research on new problems.
One effect of the war effort was a marked increase in the number of visits by members of the aeronautical industry to discuss the work in progress and a similar increase in the number of trips made to companies and other organizations to assist in the design and development of new airplanes. These visits and trips, which continued after the war, served to solve immediate problems as well as to stimulate the development of aviation through interchange of ideas.
One of the incentives for visits of the NACA personnel to companies was the availability at Langley of recording instruments for flight research. When the Langley Memorial Aeronautical Laboratory first opened at Langley Field in 1920, the director, or Chief Physicist was Frederick H. Norton, a young doctoral graduate straight from MIT. During his brief tenure at Langley, 1920-1923, starting with a staff of seven professionals, he constructed a wind tunnel, started programs in aeronautical and physical research, and established a flight research division. One of his objectives was to design recording instruments to make accurate measurements on airplanes in flight. Dr. Norton went on to become a Professor of Physics and later of Ceramics at MIT. Shortly before Norton's death at the age of 96, Dr. Hansen had a telephone conversation with him, during which Dr. Norton stated that the contribution that he made at Langley in which he took most pride was the development of recording instruments to make scientific measurements on airplanes in flight.
When I started work at Langley, the instruments used were still the same type as those developed by Norton. They incorporated a sensor to detect the physical quantity being measured. The output of this unit was mechanically linked to a small mirror, about one-quarter-inch square, that reflected a beam of light on to a strip of photographic film. The film was moved between a pair of drums by an electric motor. A second mirror was flicked up and down by a timer and reflected another light beam onto the film to give a time reference. A separate instrument was usually required for each quantity being measured. The Instrument Research Division supplied services for calibrating and installing these instruments.
At the time of WW II, the aircraft companies lacked any such facilities for recording quantities in flight. The usual technique was to construct a photopanel, a light-tight box in which a movie camera photographed an array of standard cockpit dial instruments along with a clock to give a time reference. Working up the data from these instruments, frame by frame, was exceedingly tedious.
One of my first trips was to the Republic Aircraft Corporation at Farmingdale, Long Island, New York, accompanying Gilruth and an instrument man. The purpose of the trip was to install instruments and make measurements of the rolling effectiveness of the ailerons on a new airplane derived from the P-47 Thunderbolt (figure 7.1). Later, a Navy pilot flew a captured Japanese Zero to Langley for installation of flight research instruments (figure 7.2). He returned with the airplane to Bolling Field, near Washington, D.C., and made a single flight in which many of the important maneuvers to study flying qualities were performed. I evaluated the film data and published a report on these results (ref. 7.1). Since our instrument technicians usually took several weeks to install instruments in an airplane and the program for measuring flying qualities often required about 20 flights, I was impressed by the speed of the Navy pilot's investigation. For some years after that, I tried to popularize the idea of building a self-contained set of instruments for a quick flying qualities investigation, as well as a regimen of maneuvers that could be used to conduct the investigation in one or two flights. These ideas never caught on, however,...
....because of the availability of the standard techniques and the press of urgent work.
Though Langley was well ahead of the industry in the use of flight recording instruments during the early 1940's, it was apparent to me, after having studied instrumentation under Dr. Draper at MIT, that the instruments themselves were already well behind the state of the art. The instruments had inadequate damping and picked up large amounts of engine vibration in flight. Also, gyroscopic instruments to measure attitude were unsuitable for flight recording because they usually had no means to disconnect the erection system, which caused errors in accelerated maneuvers. Later developments of magnetic tape recording and the use of multichannel oscillographs to record many quantities on one film were first introduced in telemetering systems used by the Pilotless Aircraft Research Division, but were not available for flight research. It was not until many years later, when such instruments and sensors became commercially available, that [65] the old NACA instruments were finally abandoned.
Returning to the subject of conferences and trips to industry organizations, an interesting point to mention is the large difference in the use of the NACA techniques and assistance by different companies. On the East Coast, Republic and Vought seemed to have close contact with the work in the Flight Research Division, whereas Grumman and Martin were much less involved. An example of the dependence placed by Republic on the NACA capabilities occurred shortly before I came to work. Gilruth was asked to comment on the design of the airplane that later became the P-47 Thunderbolt. Gilruth advised increasing the size of the horizontal tail because of experience with inadequate longitudinal stability on high-powered airplanes with large propellers and the resulting slipstream effects. This advice was taken by Republic, which resulted in a design with noticeably larger horizontal tail than most of the existing fighters. This feature proved valuable later because the airplane had the turbosupercharger and other equipment installed aft of the cockpit, which resulted in more rearward center-of-gravity location than originally planned. Without the larger tail, the airplane would never have had adequate longitudinal stability.
Of course, I am not familiar with the work done in the wind tunnels. Most of the companies at that time did not have their own wind tunnels, so many of them probably employed Langley wind tunnels in tests of their new designs. The Bell Aircraft Corporation, after the war, was strongly involved in the Research Airplane Program. I made several trips to Bell in connection with their proposed designs.
On the West Coast, many companies were more closely associated with the NACA Ames Research Center at Mountain View, California. Still, Douglas representatives occasionally visited Langley to discuss handling-qualities work. Boeing, throughout its existence, appeared to me to be extremely independent. The manufacturer built its own wind tunnel and rarely consulted with Langley on new developments.
Many visits were also made to military installations such as the Naval Test Pilot School at Patuxent River, Maryland, and the Flight Control Laboratory at Wright-Patterson Field. I gave a series of talks to the test pilots at Patuxent on compressibility effects on fighters capable of transonic speeds.
Several cross-country trips were made to conferences at the NACA Lewis Research Center at Cleveland and to the NACA Ames Research Center at Mountain View. In these trips, a group of about 15 engineers would get into the NACA DC-3, which was piloted by NACA test pilots. The trip to the west coast usually required about two stops, one at Memphis, Tennessee, and one in such places as China Lake, California; El Paso, Texas; or Albuquerque, New Mexico. Without these trips, I would never have seen these cities firsthand with the beautiful mountain scenery and the desert climate. I remember in my first trip to the Ames Lab that we stayed in Rickey's Motel in Sunnyvale and had a chance to see the sights of San Jose, such as the Rosicrucian Museum and the Mystery House. I was tremendously impressed by the beautiful city of San Jose, with its gardens and palm trees, and the mountains rising in the distance both in the East and the West. In those days, much of the area was still filled with orange groves. I thought it would be a wonderful place to live. Evidently many other people felt the same way, as San Jose for many years after that was the fastest growing city in the country.
