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Facultad de Ingeniería 
Departamento de Ingeniería Mecánica 
Carrera: Ingeniería Civil Aeroespacial 
 
Curso: Aerodinámica 
Información adicional 
Fuente: 
Introduction to Flight, John D. Anderson, Jr. 
McGraw-Hill, ISBN 0-07-109282-X 
 
 
 
 
 
Historical Note: The first Wind Tunnels 1 
 
 
HISTORICAL NOTE: THE FIRST WIND TUNNELS 
 
Aerospace engineering in general, and aerodynamics in particular, is an empirically 
based discipline. Discovery and development by experimental means have been its 
lifeblood, extending all the way back to George Cayley. In turn, the workhorse for such 
experiments has been predominantly the wind tunnel, so much so that today most 
aerospace industrial, government, and university laboratories have a complete spectrum 
of wind tunnels ranging from low subsonic to hypersonic speeds. 
 
It is interesting to reach back briefly into history and look at the evolution of wind tunnels. 
Amazingly enough, this history goes back more than 400 years, because the cardinal 
principle of wind tunnel testing was stated by Leonardo da Vinci near the beginning of the 
16th century as follows: 
 
For since the action of the medium upon the body is the same whether the body 
moves in a quiescent medium, or whether the particles of the medium impinge with 
the same velocity upon the quiescent body let us consider the body as if it were 
quiescent and see with what force it would be impelled by the moving medium. 
 
This is almost self-evident today, that the lift and drag of an aerodynamic body are the 
same whether it moves through the stagnant air at 100 mi/h or whether the air moves over 
the stationary body at 100 mi/h. This concept is the very foundation of wind tunnel testing. 
 
The first actual wind tunnel in history was designed and built more than 100 years ago by 
Francis Wenham in Greenwich, England, in 1871. Wenham's tunnel was nothing more than 
a 10-ft-long wooden box with a square cross section, 18 in on a side. A steam-driven fan 
at the front end blew air through the duct. There was no contour, hence no aerodynamic 
control or enhancement of flow. Plane aerodynamic surfaces were placed in the airstream 
at the end of the box, where Wenham, measured the lift and drag on weighing beams 
linked to the model. 
Información adicional – Aerodinámica 
 
 
 
 
Historical Note: The first Wind Tunnels 2 
 
 
Thirteen years later, Horatio F. Phillips, also an Englishman, built the second known wind 
tunnel in history. Again, the flow duct was a box, but Phillips used steam ejectors 
(high-speed steam nozzles) downstream of the test section to suck air through the tunnel. 
Phillips went on to conduct some pioneering airfoil testing in his tunnel. 
 
Other wind tunnels were built before the turning point in aviation in 1903. For example, the 
first wind tunnel in Russia was due to Nikolai Joukowski at the University of Moscow in 1891 
(it had a 2-in diameter). A larger, 7 in x 10 in tunnel was built in Austria in 1893 by Ludwig 
Mach, son of the famed scientist and philosopher Ernst Mach, after whom the Mach 
number is named. The first tunnel in the United States was built at the Massachusetts Institute 
of Technology in 1896 by Alfred J. Wells, who used the machine to measure the drag on a 
flat plate as a check on the whirlingarm measurements of Langley. Another tunnel in the 
United States was built by Dr. A. Heb Zahm at the Catholic University of America in 1901. In 
light of these activities, it is obvious that at the turn of the 20th century aerodynamic testing 
in wind tunnels was poised and ready to burst forth with the same energy that 
accompanied the development of the airplane itself'. 
 
It is fitting that the same two people responsible for getting the airplane off the ground 
should also have been responsible for the first concentrated series of wind tunnel tests. The 
Wright brothers in late 1901 concluded that a large part of the existing aerodynamic data 
were erroneous. This led to their construction of a 6-ft-long 16-in-square wind tunnel 
powered by a two-blade fan connected to a gasoline engine. A replica of the Wrights' 
wind tunnel is shown in Fig. 1. (Their original wind tunnel no longer exists). They designed 
and built their own balance to measure the ratios of lift to drag. Using this apparatus, 
Wilbur and Orville undertook a major program of aeronautical research between 
September 1901 and August 1902. During this time, they tested more than 200 different 
airfoil shapes manufactured out of steel. The results from these tests constitute the first 
major impact of wind tunnel testing on the development of a successful airplane. Orville 
said about their results: "Our tables of air pressure which we made in our wind tunnel would 
enable us to calculate in advance the performance of a machine." What a fantastic 
development! This was a turning point in the history of wind tunnel testing, and it had as 
much impact on that discipline as the December 17, 1903, flight had on the airplane. 
 
The rapid growth in aviation after 1903 was paced by the rapid growth of wind tunnels, 
both in numbers and in technology. For example, tunnels were built at the National 
Physical Laboratory in London in 1903; in Rome in 1903; in Moscow in 1905; in Göttingen, 
Germany (by the famous Dr. Ludwig Prandtl, originator of the boundary layer concept in 
fluid dynamics) in 1908; in Paris in 1909 (including two built by Gustave Eiffel, of tower 
fame); and again at the National Physical Laboratory in 1910 and 1912. 
 
All these tunnels, quite naturally, were low-speed facilities, but they were pioneering for 
their time. Then in 1915, with the creation of NACA, the foundation was laid for some major 
spurts in wind-tunnel design. The first NACA wind tunnel became operational at the Langley 
Información adicional – Aerodinámica 
 
 
 
 
Historical Note: The first Wind Tunnels 3 
 
Memorial Aeronautical Laboratory at Hampton, Virginia, in 1920. It had a 5-ft-diameter test 
section which accommodated models up to 3.5 ft wide. Then in 1923, in order to simulate 
the higher Reynolds numbers associated with flight, NACA built the first variable-density 
wind tunnel, a facility that could be pressurized to 20 atm in the flow and therefore obtain 
a 20-fold increase in density, hence Re, in the test section. During the 1930s and 1940s, 
subsonic wind tunnels grew larger and larger. In 1931, a NACA wind tunnel with a 30 ft x 60 
ft oval test section went into operation at Langley with a 129 mi/h maximum flow velocity. 
This was the first million-dollar tunnel in history. Later, in 1944, a 40 ft x 80 ft tunnel with a 
flow velocity of 265 mi/h was initiated at Ames Aeronautical Laboratory at Moffett Field, 
California. This is still the largest wind tunnel in the world today. Figure 2 shows the 
magnitude of such tunnels: whole airplanes can be mounted in the test section! 
 
The tunnels mentioned above were low-speed, essentially incompressible flow tunnels. 
They were the cornerstone of aeronautical testing until the 1930s and remain an important 
part of the aerodynamic scene today. However, airplane speeds were progressively 
increasing, and new wind tunnels with higher velocity capability were needed. Indeed, the 
first requirement for high-speed subsonic tunnels was established by propellers - in the 
1920s and 1930s the propeller diameters and rotational speeds were both increasing so 
as to encounter compressibility problems at the tips. This problem led NACA to build a 
12-in-diameter high-speed tunnel at Langley in 1927. It could produce a test section flow 
of 765 mi/h. In 1936, to keep up with increasing airplane speeds, Langley built a large 8-ft 
high-speed wind tunnel providing 500 mi/h. This was increased to 760 mi/h in 1945. An 
important facility was built at Ames in 1941, a 16-ft tunnel with an airspeed of 680 mi/h. A 
photograph of the Ames 16-ft tunnel is shown in Fig. 3 just to give a feeling for the massive 
size involved with such a facility.In the early 1940s, the advent of the V-2 rocket as well as the jet engine put supersonic 
flight in the minds of aeronautical engineers. Suddenly, the requirement for supersonic 
tunnels became a major factor. However, supersonic flows in the laboratory and in 
practice date farther back than this. The first supersonic nozzle was developed by Laval 
about 1880 for use with steam turbines. This is why the convergent-divergent nozzles are 
frequently called Laval nozzles. In 1905, Prandtl built a small Mach 1.5 tunnel at Gottingen 
to be used to study steam turbine flows and (of all things) the moving of sawdust around 
sawmills. 
 
The first practical supersonic wind tunnel for aerodynamic testing was developed by Dr. A. 
Busemann at Braunschweig, Germany, in the mid- 1930s. Using the "method of 
characteristics" technique, which he had developed in 1929, Busemann designed the first 
smooth supersonic nozzle contour which produced shock-free isentropic flow. He had a 
diffuser with a second throat downstream to decelerate the flow and to obtain efficient 
operation of the tunnel. A photograph of Busemann's tunnel is shown in Fig. 4. All 
supersonic tunnels today look essentially the same. 
 
Información adicional – Aerodinámica 
 
 
 
 
Historical Note: The first Wind Tunnels 4 
 
Working from Busemann's example, the Germans built two major supersonic tunnels at their 
research complex at Peenemunde during World War II. These were used for research and 
development of the V-2 rocket. After the war, these tunnels were moved almost in total to 
the U.S. Naval Ordnance Laboratory (later, one was moved to the University of Maryland), 
where they are still in use today. However, the first supersonic tunnel built in the United 
States was designed by Theodore von Karman and his colleagues at the California Institute 
of Technology in 1944 and was built and operated at the Army Ballistics Research 
Laboratory at Aberdeen, Maryland, under contract with Cal Tech. Then the 1950s saw a 
virtual harvest of supersonic wind tunnels, one of the largest being the 16 ft x 16 ft 
continuously operated supersonic tunnel of the Air Force at the Arnold Engineering 
Development Center (AEDC) in Tennessee. 
 
About this time, the development of the intercontinental ballistic missile (ICBM) was on the 
horizon, soon to be followed by the space program of the 1960s. Flight vehicles were soon 
to encounter velocities as high as 36,000 ft/s in the atmosphere - hypersonic velocities. In 
turn, hypersonic wind tunnels (M > 5) were suddenly in demand. The first hypersonic wind 
tunnel was operated by NACA at Langley in 1947. It had an 11-in-square test section 
capable of Mach 7. Three years later, another hypersonic tunnel went into operation at 
the Naval Ordnance Laboratory. These tunnels are distinctly different from their supersonic 
relatives in that, to obtain hypersonic speeds, the flow has to be expanded so far that the 
temperature decreases to the point of liquefying the air. To prevent this, all hypersonic 
tunnels, both old and new, have to have the reservoir gas heated to temperatures far 
above room temperature before its expansion through the nozzle. Heat transfer is a 
problem for high-speed flight vehicles, and such heating problems feed right down to the 
ground-testing facilities for such vehicles. 
 
In summary, modern wind tunnel facilities range across the whole spectrum of flight 
velocities, from low subsonic to hypersonic speeds. These facilities are part of the everyday 
life of aerospace engineering; hopefully, this brief historical sketch has provided some 
insight into their tradition and development. 
Información adicional – Aerodinámica 
 
 
 
 
Historical Note: The first Wind Tunnels 5 
 
 
Figure 1: A replica of the Wright brothers' wind tunnel in a workroom behind the Wrights' 
 bicycle shop, now in Greenfield Village, Dearborn, Michigan. 
 
Figure 2: A subsonic wind tunnel large enough to test a full-size airplane. The NASA Langley 
Research Center 30 ft x 60 ft tunnel 
Información adicional – Aerodinámica 
 
 
 
 
Historical Note: The first Wind Tunnels 6 
 
 
Figure 3: The Ames 16-ft high-speed subsonic wind tunnel, illustrating the massive size that 
goes along with such a wind tunnel complex. 
 
 
Figure 4: The first practical supersonic wind tunnel, built by A. Busemann in the mid-1930s.