The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets and personnel were transferred to the newly created
National Aeronautics and Space Administration
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding th ...
(NASA). NACA is an initialism, i.e., pronounced as individual letters, rather than as a whole word (as was NASA during the early years after being established).
Among other advancements, NACA
research and development
Research and development (R&D or R+D), known in Europe as research and technological development (RTD), is the set of innovative activities undertaken by corporations or governments in developing new services or products, and improving existi ...
produced the
NACA duct
A NACA duct, also sometimes called a NACA scoop or NACA inlet, is a common form of low- drag air inlet design, originally developed by the U.S. National Advisory Committee for Aeronautics (NACA), the precursor to NASA, in 1945.
Design
Prior su ...
, a type of air intake used in modern automotive applications, the
NACA cowling
The NACA cowling is a type of aerodynamic fairing used to streamline radial engines installed on airplanes. It was developed by Fred Weick of the National Advisory Committee for Aeronautics (NACA) in 1927. It was a major advance in aerodynamic ...
, and several series of
NACA airfoil
The NACA airfoils are airfoil shapes for aircraft wings developed by the National Advisory Committee for Aeronautics (NACA). The shape of the NACA airfoils is described using a series of digits following the word "NACA". The parameters in the ...
s, which are still used in aircraft manufacturing.
During World War II, NACA was described as "The Force Behind Our Air Supremacy" due to its key role in producing working superchargers for high altitude bombers, and for producing the laminar wing profiles for the
North American P-51 Mustang
The North American Aviation P-51 Mustang is an American long-range, single-seat fighter aircraft, fighter and fighter-bomber used during World War II and the Korean War, among other conflicts. The Mustang was designed in April 1940 by a team ...
.
NACA also helped in developing the
area rule
The Whitcomb area rule, named after NACA engineer Richard Whitcomb and also called the transonic area rule, is a design procedure used to reduce an aircraft's drag at transonic speeds which occur between about Mach 0.75 and 1.2. For supersonic ...
that is used on all modern
supersonic aircraft
A supersonic aircraft is an aircraft capable of supersonic flight, that is, flying faster than the speed of sound (Mach number 1). Supersonic speed, Supersonic aircraft were developed in the second half of the twentieth century. Supersonic airc ...
, and conducted the key compressibility research that enabled the
Bell X-1
The Bell X-1 (Bell Model 44) is a rocket engine–powered aircraft, designated originally as the XS-1, and was a joint National Advisory Committee for Aeronautics– U.S. Army Air Forces–U.S. Air Force supersonic research project built by Be ...
to break the sound barrier.
Origins
![NACA credo](https://upload.wikimedia.org/wikipedia/commons/3/30/NACA_credo.jpg)
NACA was established on March 13, 1915, by the federal government through enabling legislation as an emergency measure during
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
to promote industry, academic, and government coordination on war-related projects. It was modeled on similar national agencies found in Europe: the French ''L'Etablissement Central de l'Aérostation Militaire'' in
Meudon
Meudon () is a municipality in the southwestern suburbs of Paris, France. It is in the département of Hauts-de-Seine. It is located from the center of Paris. The city is known for many historic monuments and some extraordinary trees. One of t ...
(now ''
Office National d'Etudes et de Recherches Aerospatiales
The Office National d'Etudes et de Recherches Aérospatiales (ONERA) is the French national aerospace research centre. It is a public establishment with industrial and commercial operations, and carries out application-oriented research to supp ...
''), the German Aerodynamic Laboratory of the
University of Göttingen
The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...
, and the Russian Aerodynamic Institute of Koutchino (replaced in 1918 with the
Central Aerohydrodynamic Institute (TsAGI), which is still in existence). The most influential agency upon which the NACA was based was the British
Advisory Committee for Aeronautics
The Advisory Committee for Aeronautics (ACA) was a UK agency founded on 30 April 1909, to undertake, promote, and institutionalize aeronautical research. In 1919 it was renamed the Aeronautical Research Committee, later becoming the Aeronautical ...
.
In December 1912, President
William Howard Taft
William Howard Taft (September 15, 1857March 8, 1930) was the 27th president of the United States (1909–1913) and the tenth chief justice of the United States (1921–1930), the only person to have held both offices. Taft was elected pr ...
had appointed a National Aerodynamical Laboratory Commission chaired by
Robert S. Woodward, president of the
Carnegie Institution of Washington
The Carnegie Institution of Washington (the organization's legal name), known also for public purposes as the Carnegie Institution for Science (CIS), is an organization in the United States established to fund and perform scientific research. Th ...
. Legislation was introduced in both houses of Congress early in January 1913 to approve the commission, but when it came to a vote, the legislation was defeated.
Charles D. Walcott
Charles Doolittle Walcott (March 31, 1850February 9, 1927) was an American paleontologist, administrator of the Smithsonian Institution from 1907 to 1927, and director of the United States Geological Survey.Wonderful Life (book) by Stephen Jay Go ...
, secretary of the
Smithsonian Institution
The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Founded ...
from 1907 to 1927, took up the effort, and in January 1915, Senator
Benjamin R. Tillman
Benjamin Ryan Tillman (August 11, 1847 – July 3, 1918) was an American politician of the Democratic Party who served as governor of South Carolina from 1890 to 1894, and as a United States Senator from 1895 until his death in 1918. A whi ...
, and Representative
Ernest W. Roberts introduced identical resolutions recommending the creation of an advisory committee as outlined by Walcott. The purpose of the committee was "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".
Assistant Secretary of the Navy
Assistant Secretary of the Navy (ASN) is the title given to certain civilian senior officials in the United States Department of the Navy.
From 1861 to 1954, the Assistant Secretary of the Navy was the second-highest civilian office in the Depar ...
Franklin D. Roosevelt
Franklin Delano Roosevelt (; ; January 30, 1882April 12, 1945), often referred to by his initials FDR, was an American politician and attorney who served as the 32nd president of the United States from 1933 until his death in 1945. As the ...
wrote that he "heartily
ndorsedthe principle" on which the legislation was based. Walcott suggested the tactic of adding the resolution to the Naval Appropriations Bill.
According to one source, "The enabling legislation for the NACA slipped through almost unnoticed as a rider attached to the Naval Appropriation Bill, on March 3, 1915." The committee of 12 people, all unpaid, were allocated a budget of $5,000 per year.
President
Woodrow Wilson
Thomas Woodrow Wilson (December 28, 1856February 3, 1924) was an American politician and academic who served as the 28th president of the United States from 1913 to 1921. A member of the Democratic Party, Wilson served as the president of ...
signed it into law the same day, thus formally creating the Advisory Committee for Aeronautics, as it was called in the legislation, on the last day of the
63rd Congress.
The act of Congress creating NACA, approved March 3, 1915, reads, "...It shall be the duty of the advisory committee for aeronautics to supervise and direct the scientific study of the problems of flight with a view to their practical solution. ... "
Research
![The NACA Test Force - GPN-2000-000083](https://upload.wikimedia.org/wikipedia/commons/c/ca/The_NACA_Test_Force_-_GPN-2000-000083.jpg)
On January 29, 1920, President Wilson appointed pioneering flier and aviation engineer
Orville Wright to NACA's board. By the early 1920s, it had adopted a new and more ambitious mission: to promote military and civilian aviation through applied research that looked beyond current needs. NACA researchers pursued this mission through the agency's impressive collection of in-house wind tunnels, engine test stands, and flight test facilities. Commercial and military clients were also permitted to use NACA facilities on a contract basis.
;Facilities
*
Langley Memorial Aeronautical Laboratory (
Hampton, Virginia
Hampton () is an independent city (United States), independent city in the Commonwealth (U.S. state), Commonwealth of Virginia in the United States. As of the 2020 United States Census, 2020 census, the population was 137,148. It is the List ...
)
*
Ames Aeronautical Laboratory
The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laborat ...
(
Moffett Field
Moffett Federal Airfield , also known as Moffett Field, is a joint civil-military airport located in an Local government in California#Counties, unincorporated part of Santa Clara County, California, Santa Clara County, California, United States, ...
)
*Aircraft Engine Research Laboratory (
Lewis Research Center
NASA John H. Glenn Research Center at Lewis Field is a NASA center within the cities of Brook Park and Cleveland between Cleveland Hopkins International Airport and the Rocky River Reservation of Cleveland Metroparks, with a subsidiary facilit ...
)
*
Muroc Flight Test Unit
Muroc (also, Rogers, Rod, Yucca, and Rodriguez) is a former settlement in Kern County, California in the Mojave Desert.
It was located on Rogers Dry Lake east of Edwards, at an elevation of 2283 feet (696 m).
Muroc still appeared on maps as o ...
(
Edwards Air Force Base
Edwards Air Force Base (AFB) is a United States Air Force installation in California. Most of the base sits in Kern County, but its eastern end is in San Bernardino County and a southern arm is in Los Angeles County. The hub of the base is E ...
)
In 1922, NACA had 100 employees. By 1938, it had 426. In addition to formal assignments, staff were encouraged to pursue unauthorized "bootleg" research, provided that it was not too exotic. The result was a long string of fundamental breakthroughs, including "
thin airfoil theory
An airfoil (American English) or aerofoil (British English) is the cross-sectional shape of an object whose motion through a gas is capable of generating significant lift, such as a wing, a sail, or the blades of propeller, rotor, or turbine. ...
" (1920s), "
NACA engine cowl" (1930s), the "
NACA airfoil
The NACA airfoils are airfoil shapes for aircraft wings developed by the National Advisory Committee for Aeronautics (NACA). The shape of the NACA airfoils is described using a series of digits following the word "NACA". The parameters in the ...
" series (1940s), and the "
area rule
The Whitcomb area rule, named after NACA engineer Richard Whitcomb and also called the transonic area rule, is a design procedure used to reduce an aircraft's drag at transonic speeds which occur between about Mach 0.75 and 1.2. For supersonic ...
" for supersonic aircraft (1950s). On the other hand, NACA's 1941 refusal to increase airspeed in their wind tunnels set
Lockheed back a year in their quest to solve the problem of
compressibility
In thermodynamics and fluid mechanics, the compressibility (also known as the coefficient of compressibility or, if the temperature is held constant, the isothermal compressibility) is a measure of the instantaneous relative volume change of a fl ...
encountered in high speed dives made by the
Lockheed P-38 Lightning
The Lockheed P-38 Lightning is an American single-seat, twin piston-engined fighter aircraft that was used during World War II. Developed for the United States Army Air Corps by the Lockheed Corporation, the P-38 incorporated a distinctive twi ...
.
![Model in Supersonic Wind Tunnel GPN-2000-001631](https://upload.wikimedia.org/wikipedia/commons/f/f9/Model_in_Supersonic_Wind_Tunnel_GPN-2000-001631.jpg)
The full-size Langley wind tunnel operated at no more than and the then-recent tunnels at Moffett could only reach . These were speeds Lockheed engineers considered useless for their purposes. General
Henry H. Arnold
Henry Harley Arnold (June 25, 1886 – January 15, 1950) was an American general officer holding the ranks of General of the Army and later, General of the Air Force. Arnold was an aviation pioneer, Chief of the Air Corps (1938–1941), ...
took up the matter and overruled NACA objections to higher air speeds. NACA built a handful of new high-speed wind tunnels, and Mach 0.75 () was reached at Moffett's wind tunnel late in 1942.
Wind tunnels
NACA's first
wind tunnel
Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...
was formally dedicated at
Langley Memorial Aeronautical Laboratory on June 11, 1920. It was the first of many now-famous NACA and NASA wind tunnels. Although this specific wind tunnel was not unique or advanced, it enabled NACA engineers and scientists to develop and test new and advanced concepts in
aerodynamics
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...
and to improve future wind tunnel design.
#Atmospheric 5-ft wind tunnel (1920)
#
Variable Density Tunnel
The Variable Density Tunnel (VDT) was the second wind tunnel at the National Advisory Committee for Aeronautics (NACA) Langley Research Center. Proposed by German aerospace engineer, Max Munk in May, 1921, it was the world's first variable density ...
(1922)
#
Propeller Research Tunnel
The Propeller Research Tunnel (PRT) was the first full-scale wind tunnel at the National Advisory Committee for Aeronautics (NACA) Langley Research Center, and the third at the facility. It was in use between 1927 and 1950 and was instrumental i ...
(1927)
#High-speed 11-in wind tunnel (1928)
#Vertical 5-ft wind tunnel (1929)
#Atmospheric 7- by 10-ft wind tunnel (1930)
#Full-scale 30- by 60-ft tunnel (1931)
Influence on World War II technology
In the years immediately preceding World War II, NACA was involved in the development of several designs that served key roles in the war effort. When engineers at a major engine manufacturer were having issues producing
supercharger
In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement.
The current categorisation is that a supercharger is a form of forced induct ...
s that would allow the
Boeing B-17 Flying Fortress
The Boeing B-17 Flying Fortress is a four-engined heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Relatively fast and high-flying for a bomber of its era, the B-17 was used primarily in the European Theater ...
to maintain power at high altitude, a team of engineers from NACA solved the problems and created the standards and testing methods used to produce effective superchargers in the future. This enabled the B-17 to be used as a key aircraft in the war effort. The designs and information gained from NACA research on the B-17 were used in nearly every major U.S. military
powerplant
Propulsion is the generation of force by any combination of pushing or pulling to modify the translational motion of an object, which is typically a rigid body (or an articulated rigid body) but may also concern a fluid. The term is derived from ...
of the Second World War. Nearly every aircraft used some form of
forced induction
In an internal combustion engine, forced induction is where turbocharging or supercharging is used to increase the density of the intake air. Engines without forced induction are classified as naturally aspirated.
Operating principle Overvi ...
that relied on information developed by NACA. Because of this, U.S.-produced aircraft had a significant power advantage above 15,000 feet, which was never fully countered by Axis forces.
After the war had begun, the British government sent a request to
North American Aviation
North American Aviation (NAA) was a major American aerospace manufacturer that designed and built several notable aircraft and spacecraft. Its products included: the T-6 Texan trainer, the P-51 Mustang fighter, the B-25 Mitchell bomber, the F ...
for a new fighter. The offered
P-40 Tomahawk
The Curtiss P-40 Warhawk is an American single-engined, single-seat, all-metal fighter and ground-attack aircraft that first flew in 1938. The P-40 design was a modification of the previous Curtiss P-36 Hawk which reduced development time and ...
fighters were considered too outdated to be a feasible front line fighter by European standards, and so North American began development of a new aircraft. The British government chose a NACA-developed airfoil for the fighter, which enabled it to perform dramatically better than previous models. This aircraft became known as the
P-51 Mustang
The North American Aviation P-51 Mustang is an American long-range, single-seat fighter and fighter-bomber used during World War II and the Korean War, among other conflicts. The Mustang was designed in April 1940 by a team headed by James ...
.
Supersonic research
![NACA-Ames-1958](https://upload.wikimedia.org/wikipedia/commons/8/87/NACA-Ames-1958.jpg)
Although the
Bell X-1
The Bell X-1 (Bell Model 44) is a rocket engine–powered aircraft, designated originally as the XS-1, and was a joint National Advisory Committee for Aeronautics– U.S. Army Air Forces–U.S. Air Force supersonic research project built by Be ...
was commissioned by the Air Force and flown by Air Force test pilot
Chuck Yeager
Brigadier General Charles Elwood Yeager ( , February 13, 1923December 7, 2020) was a United States Air Force officer, flying ace, and record-setting test pilot who in October 1947 became the first pilot in history confirmed to have exceeded the ...
, when it exceeded
Mach 1 NACA was officially in charge of the testing and development of the aircraft. NACA ran the experiments and data collection, and the bulk of the research used to develop the aircraft came from NACA engineer
John Stack, the head of NACA's compressibility division.
Compressibility is a major issue as aircraft approach Mach 1, and research into solving the problem drew heavily on information collected during previous NACA wind tunnel testing to assist Lockheed with the P-38 Lightning.
The X-1 program was first envisioned in 1944 when a former NACA engineer working for Bell Aircraft approached the Army for funding of a supersonic test aircraft. Neither the Army nor Bell had any experience in this area, so the majority of research came from the NACA Compressibility Research Division, which had been operating for more than a year by the time Bell began conceptual designs. The Compressibility Research Division also had years of additional research and data to pull from, as its head engineer was previously head of the high speed wind tunnel division, which itself had nearly a decade of high speed test data by that time. Due to the importance of NACA involvement, Stack was personally awarded the Collier Trophy along with the owner of Bell Aircraft and test pilot Chuck Yeager.
In 1951, NACA Engineer
Richard Whitcomb determined the
area rule
The Whitcomb area rule, named after NACA engineer Richard Whitcomb and also called the transonic area rule, is a design procedure used to reduce an aircraft's drag at transonic speeds which occur between about Mach 0.75 and 1.2. For supersonic ...
that explained
transonic
Transonic (or transsonic) flow is air flowing around an object at a speed that generates regions of both subsonic and supersonic airflow around that object. The exact range of speeds depends on the object's critical Mach number, but transonic ...
flow over an aircraft. The first uses of this theory were on the
Convair F-102 project and the
F11F Tiger
The Grumman F11F/F-11 Tiger is a supersonic, single-seat carrier-based United States Navy fighter aircraft in operation during the 1950s and 1960s. Originally designated the F11F Tiger in April 1955 under the pre-1962 Navy designation system, i ...
. The F-102 was meant to be a supersonic interceptor, but it was unable to exceed the speed of sound, despite the best effort of Convair engineers. The F-102 had actually already begun production when this was discovered, so NACA engineers were sent to quickly solve the problem at hand. The production line had to be modified to allow the modification of F-102s already in production to allow them to use the area rule. (Aircraft so altered were known as "area ruled" aircraft.) The design changes allowed the aircraft to exceed Mach 1, but only by a small margin, as the rest of the Convair design was not optimized for this. As the F-11F was the first design to incorporate this during initial design, it was able to break the sound barrier without having to use afterburner.
Because the area rule was initially classified, it took several years for Whitcomb to be recognized for his accomplishment. In 1955 he was awarded the Collier Trophy for his work on both the Tiger and the F-102.
The most important design resulting from the area rule was the
B-58 Hustler
The Convair B-58 Hustler, designed and produced by American aircraft manufacturer Convair, was the first operational bomber capable of Mach 2 flight.
The B-58 was developed during the 1950s for the United States Air Force (USAF) Strategic Air ...
, which was already in development at the time. It was redesigned to take the area rule into effect, allowing greatly improved performance. This was the first US supersonic bomber, and was capable of Mach 2 at a time when Soviet fighters had only just attained that speed months earlier.
The area rule concept is now used in designing all transonic and supersonic aircraft.
NACA experience provided a powerful model for
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
research, the postwar government laboratories, and NACA's successor, the
National Aeronautics and Space Administration
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding th ...
(NASA).
NACA also participated in development of the first aircraft to fly to the "edge of space", North American's
X-15
The North American X-15 is a hypersonic rocket-powered aircraft. It was operated by the United States Air Force and the National Aeronautics and Space Administration as part of the X-plane series of experimental aircraft. The X-15 set speed ...
. NACA airfoils are still used on modern aircraft.
Chairmen
Transformation into NASA
Special Committee on Space Technology
![NACA's Special Committee on Space Technology](https://upload.wikimedia.org/wikipedia/commons/0/0d/NACA%27s_Special_Committee_on_Space_Technology.jpg)
On November 21, 1957,
Hugh Dryden, NACA's director, established the Special Committee on Space Technology.
The committee, also called the Stever Committee after its chairman,
Guyford Stever
Horton Guyford Stever (October 24, 1916 – April 9, 2010) was an United States of America, American Administrator of the Government, administrator, physicist, educator, and engineer. He was a director of the National Science Foundation (from Febru ...
, was a special steering committee that was formed with the mandate to coordinate various branches of the federal government, private companies as well as universities within the United States with NACA's objectives and also harness their expertise in order to develop a space program.
Wernher von Braun
Wernher Magnus Maximilian Freiherr von Braun ( , ; 23 March 191216 June 1977) was a German and American aerospace engineer and space architect. He was a member of the Nazi Party and Allgemeine SS, as well as the leading figure in the develop ...
, technical director at the
US Army's Ballistic Missile Agency would have a
Jupiter C
The Jupiter-C was an American research and development vehicle developed from the Jupiter-A. Jupiter-C was used for three unmanned sub-orbital spaceflights in 1956 and 1957 to test re-entry nosecones that were later to be deployed on the more ...
rocket ready to launch a satellite in 1956, only to have it delayed,
and the Soviets would launch ''
Sputnik 1
Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for t ...
'' in October 1957.
On January 14, 1958, Dryden published "A National Research Program for Space Technology", which stated:
On March 5, 1958,
James Killian
James Rhyne Killian Jr. (July 24, 1904 – January 29, 1988) was the 10th president of the Massachusetts Institute of Technology, from 1948 until 1959.
Early life
Killian was born on July 24, 1904, in Blacksburg, South Carolina. His father w ...
, who chaired the
President's Science Advisory Committee
The President's Science Advisory Committee (PSAC) was created on November 21, 1957, by President of the United States Dwight D. Eisenhower, as a direct response to the Soviet launching of the Sputnik 1 and Sputnik 2 satellites. PSAC was an upgrade ...
, wrote a memorandum to the President
Dwight D. Eisenhower
Dwight David "Ike" Eisenhower (born David Dwight Eisenhower; ; October 14, 1890 – March 28, 1969) was an American military officer and statesman who served as the 34th president of the United States from 1953 to 1961. During World War II, ...
. Titled, "Organization for Civil Space Programs", it encouraged the President to sanction the creation of NASA. He wrote that a civil space program should be based on a "strengthened and redesignated" NACA, indicating that NACA was a "going Federal research agency" with 7,500 employees and $300 million worth of facilities, which could expand its research program "with a minimum of delay".
Members
As of their meeting on May 26, 1958, committee members, starting clockwise from the left of the above picture:
References
Further reading
John Henry, et al. '' Orders of Magnitude: A History of the NACA and NASA, 1915-1990''Alex Roland. ''Model Research: The National Advisory Committee for Aeronautics, 1915-1958.''James Hansen. ''Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958.''Michael H. Gorn, ''Expanding the envelope – Flight Research at NACA and NASA.''
External links
*The NASA Technical Reports Server provides access to
collectionof 14,469 NACA documents dating from 1917.
Aerospaceweb.org: Information on NACA airfoil series edited by Pamela E. Mack.
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