by Airman 1st Class R. Alex Durbin
633rd Air Base Wing Public Affairs
10/23/2012 - JOINT BASE LANGLEY-EUSTIS, Va. (AFNS) -- The
grainy film showed a round ship floating out of a hangar. Its silver,
aluminum exterior glinted in the sun as it hovered a few feet off the
ground. As it glided over a pool of water, it kicked debris into the air
and the glass canopies of the two cockpits were showered with grass and
gravel as the saucer flew forward.
It may seem like a scene out of a classic Hollywood blockbuster, but the
footage is documentation of testing held by the U.S. government on an
experimental aircraft. This prototype, and fascinating piece of American
history, sits on display at the National U.S. Air Force Museum at
Wright-Patterson Air Force Base, Ohio, and another resides at U.S. Army
Transportation Museum at Fort Eustis, Va., where plans are underway for
its restoration.
With its round design standing at nearly five feet tall and 18 feet
wide, the Avro Canada VZ-9AV Avrocar looks like something out of a 1950s
science-fiction film. While it may look like something a martian would
fly, the Avrocar is anything but science fiction.
Newly declassified documents concerning the Avrocar project were
released Oct. 8, when they were published by the U.S. National Archives.
Information about the aircraft has been available for years, but the
documents now include diagrams that clearly demonstrate the scope of the
project.
"The Avrocar was a good start, and the first step on a long road to
discovering technology we use today," said Jeff Underwood, National
Museum of the U.S. Air Force historian. "Although the project was never
implemented, it serves a successful teaching tool."
The Avrocar was the result of a Canadian effort to develop a supersonic
fighter-bomber, capable of vertical takeoff and landing, in the early
1950s. The Idea of what was to become the Avrocar was originally
envisioned by British Aircraft designer, Jack Carver Meadows Frost.
A.V. Roe, a Canadian aircraft manufacturing company, along with Frost,
based its design concept for the Avrocar on using the exhaust from
turbojet engines to drive a circular rotor to produce thrust. By
directing this thrust downward, it was believed the turbo-rotor could
create a cushion of air under the aircraft, allowing it to float a few
feet off the ground, as well as accelerate to high speeds at higher
altitudes.
The Canadian government provided initial funding for the prototype, but
dropped the project when it became too expensive. Avro offered the
project to the U.S. government, and the U.S. Army and U.S. Air Force
took over testing in 1955. Although the project primarily remained in
Canada, it was owned and controlled by the U.S. government.
While testing was a combined effort, both services were interested in
the project for different reasons. The Army was interested in a durable
and adaptable, all-terrain transport and reconnaissance aircraft. The
Army Intended the Avrocar to replace their light observation craft and
helicopters.
The Air Force was interested in the Avrocar's vertical take-off and
landing capabilities, which could potentially hover below enemy radar
and accelerate to supersonic speed.
Research data originally indicated that a circular design may have
satisfied both service's requirements. A.V. Roe built two, small test
models to prove the concept.
"Engineers predicted the Avrocar would be able to reach heights of
nearly 10,000 feet," said Marc Sammis, U.S. Army Transportation Museum
curator. "Unfortunately, it was soon discovered that the aircraft
wouldn't be able to perform as well as predicted."
Tests with scale models at Wright-Patterson AFB indicated the cushion of
air under the Avrocar would become unstable when the aircraft passed
roughly three feet off the ground. It was determined the aircraft was
not incapable of reaching supersonic speeds, nor would the circular
shape of the craft allow the Avrocar to have stealth capabilities.
Although the aircraft did not meet the expectations of the Air Force,
testing was continued to examine if a suitable model could be developed
to fit the Army's needs.
The first prototype was sent to the National Aeronautics and Space
Administration's Ames Research Center at Moffett Field, Calif.
Wind-tunnel tests proved the aircraft had insufficient control for high
speed flight and was aerodynamically unstable. Although engineers
attempted to perfect the design, the project was marred with problems.
"Once engineers would fix a problem, another would arise because of the modification," said Sammis.
The second Avrocar prototype underwent flight tests. Project engineers
discovered once the craft rose beyond three feet above the ground, it
displayed uncontrollable pitch and roll motions. The lack of computer
technology and design flaws required pilots to control each engine
separately, making it very difficult even for two pilots to properly
control.
In December 1961, project leaders discovered the Avrocar could not reach
a maximum speed higher than 35 mph. This, along with the crafts other
shortcomings, led them to cancel testing permanently.
"This project was far ahead of its time," said Underwood. " It was a
perfect concept, but the technology of the time wasn't advanced enough."
Although the testing was deemed a failure by the engineers and pilots
who spearheaded the experimentation, the implications of the Avrocar's
technology had far reaching results.
"Just because the tests weren't successful, doesn't mean it was a
failure," said Underwood. "This experiment started engineers down a path
to more innovative concepts based on what was learned."
Technology used by many aircraft, like the AV-8B Harrier II, V-22 Osprey
and the F-22 Raptor, can trace its history back to the Avrocar.
Concepts gleaned from the Avrocar testing are still being implemented
today with the development of the U.S. Marine's variant of the F-35
Lightning II. The F-35B will offer the capability to land vertically,
making it the first aircraft in history to combine both stealth and
vertical landing capabilities.
"Aircraft with capabilities to take-off and land vertically have their
roots in this experiment," said Sammis. "These capabilities come from a
long line of experimentation which started with the Avrocar."
Tuesday, October 23, 2012
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