The National Advisory Committee for
Aeronautics was a U.S. 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 transferred to the
newly created National Aeronautics and
Space Administration. NACA was
pronounced as individual letters, rather
than as an acronym.
Among other advancements, NACA research
and development produced the NACA duct,
a type of air intake used in modern
automotive applications, the NACA
cowling, and several series of NACA
airfoils 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 cutting edge wing
profiles for the North American P-51
Mustang. NACA was also key in developing
the area rule that is used on all modern
supersonic aircraft, and was responsible
for the key compressibility research
that allowed the Bell X-1 to break the
sound barrier.
Origins
NACA began as an emergency measure
during World War I to promote
industrygovernment coordination on
war-related projects. It was modeled on
similar national agencies found in
Europe. Such agencies were the French
L’Etablissement Central de l’Aérostation
Militaire in Meudon, the German
Aerodynamic Laboratory of the University
of Göttingen, and the Russian
Aerodynamic Institute of Koutchino with
a Soviet successor agency, the "Central
Aerohydrodynamic Institute", still known
in post-Soviet Russia as TsAGI today, in
1918. However, the most influential
agency upon which the NACA was based was
the British Advisory Committee for
Aeronautics.
In December 1912, President William
Howard Taft had appointed a National
Aerodynamical Laboratory Commission
chaired by Robert S. Woodward, president
of the Carnegie Institution of
Washington. 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 – secretary of the
Smithsonian Institution from 1907 to
1927 – took up the effort, and in
January 1915, Senator Benjamin R.
Tillman, 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 Franklin D.
Roosevelt wrote that he "heartily
[endorsed] the principle" on which the
legislation was based. Walcott then
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 3 March
1915." The committee of 12 people, all
unpaid, were allocated a budget of
$5,000 per year.
President Woodrow Wilson 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 at NACA
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
Ames Aeronautical Laboratory
Aircraft Engine Research Laboratory
Muroc Flight Test Unit
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", "NACA engine cowl", the "NACA
airfoil" series, and the "area rule" for
supersonic aircraft. 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 encountered
in high speed dives made by the Lockheed
P-38 Lightning.
The full-size 30-by-60-foot Langley wind
tunnel operated at no more than 100
miles per hour and the then-recent
7-by-10-foot tunnels at Moffett could
only reach 250 miles per hour. These
were speeds Lockheed engineers
considered useless for their purposes.
General Henry H. Arnold 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 16-foot
wind tunnel late in 1942.
Influence on technology immediately
before and during World War II
In the years immediately preceding World
War II, NACA was involved in several
designs that went on to serve key roles
in the war effort. When engineers at a
major engine manufacturer were having
issues producing superchargers that
would allow the Boeing B-17 Flying
Fortress to maintain power at high
altitude, it was a team of engineers
from NACA who solved the problems and
who created the standards and testing
methods used to produce effective
superchargers in the future. This
allowed the B-17 to become a key
aircraft in the war effort. The designs
and information gained from NACA
research on the B-17 were utilized in
nearly every major U.S. military
powerplant of the Second World War.
Nearly every aircraft used some form of
forced induction 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 for a new fighter.
Their existing P-40 fighter was
considered too outdated to be a feasible
front line fighter, and so the
development of a new aircraft was begun.
A NACA developed airfoil was chosen by
the British government for the fighter,
which allowed it to perform dramatically
better than previous models. The
aircraft became the P-51 Mustang.
NACA involvement in supersonic research
Although the Bell X-1 was commissioned
by the Air Force and flown by Air Force
test pilot Chuck Yeager, 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 compressibility division. 
Compressibility is a major issue as
aircraft approach Mach 1, and research
into solving the problem drew heavily on
information collected from Lockheed
engineers solving the P-38's dive
difficulties.
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 that explained
transonic flow over an aircraft. The
first use of this theory was on the U.S.
Air Force Convair F-102 project. 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. 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.
The area rule was immediately adapted by
Grumman to modify its F9F Cougar, an
already successful naval fighter. The
result was the F11F Tiger. The area rule
was used to design the Vought F-8
Crusader.
The most important design resulting from
the area rule was the B-58 Hustler. 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 research, the
postwar government laboratories, and
NACA's successor, the National
Aeronautics and Space Administration.
NACA also participated in development of
the first aircraft to fly to the "edge
of space", North American's X-15. NACA
airfoils are still used on modern
aircraft.
Special Committee on Space Technology
On 21 November 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, 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 would have a Jupiter C
rocket ready to launch a satellite in
1956, only to have it delayed, and the
Soviets would launch Sputnik 1 in
October 1957.
Transformation into NASA
On January 14, 1958, Dryden published "A
National Research Program for Space
Technology," which stated:
On March 5, 1958, James Killian, who
chaired the President's Science Advisory
Committee, wrote a memorandum to the
President Dwight D. Eisenhower. 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."
NASA Advisory Council
With the creation of NASA in 1958, the
NACA was abolished, and its research
centers – Ames Research Center, Lewis
Research Center, and Langley
Aeronautical Laboratory – were
incorporated within the new space and
aeronautics agency along with some
elements of the U.S. Army and U.S. Navy.
In 1967, Congress directed NASA to form
an Aerospace Safety Advisory Panel to
advise the NASA Administrator on safety
issues and hazards in NASA's aerospace
programs. In addition, there were the
Space Program Advisory Council and the
Research and Technology Advisory
Council.
In 1977, these were all combined to form
the NASA Advisory Council which is the
successor to the National Advisory
Committee for Aeronautics.
NACA wind tunnels
NACA's first wind tunnel 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 and to improve future wind
tunnel design.
Atmospheric 5-ft wind tunnel
Variable Density Tunnel
Propeller research tunnel
High-speed 11-in wind tunnel
Vertical 5-ft wind tunnel
Atmospheric 7- by 10-ft wind tunnel
Full-scale 30- by 60-ft tunnel
NACA chairmen
George P. Scriven
William F. Durand
John R. Freeman
Charles Doolittle Walcott
Joseph Sweetman Ames
Vannevar Bush
Jerome C. Hunsaker
James H. Doolittle
Members of Special Committee on Space
Technology
As of their meeting on 26 May 1958,
committee members, starting clockwise
from the left of the above picture:
Footnotes and 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
U.S. Centennial of Flight Commission:
The National Advisory Committee for
Aeronautics
The NASA Technical Reports Server
provides access to a collection of
14,469 NACA documents dating from 1917.
Aerospaceweb.org: Information on NACA
airfoil series
Nasa.gov: "From Engineering Science to
Big Science" — The NACA and NASA Collier
Trophy Research Project Winners, edited
by Pamela E. Mack.
