Avrocar (aircraft)
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The VZ-9- AV Avrocar was a secret U.S. military project carried out in the early years of the Cold War by the Avro Aircraft Ltd. of Malton, Ontario.
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[edit] Description
The Avrocar utilized (or at least was intended to exploit) the Coandă effect to create a vertical take-off and landing (VTOL) aircraft. It had a disc shape, and used three jet turbine engines to create thrust to lift the craft high off the ground. In the air, it would have resembled a flying saucer. Thrust from the engines was also diverted out the rim of the saucer to provide stability and helicopter-like performance.
[edit] History
The project designer was John Carver Meadows "Jack" Frost who had joined Avro Canada in June 1947 after working for several British firms. He had been with de Havilland since 1942 and had worked on the de Havilland Vampire jet fighter and more recently, the D.H.108 Swallow supersonic aircraft. At Avro Canada, he had worked on the Avro CF-100 before starting on a flying disc design in a research team known as the "Special Projects Group."
[edit] Special Projects Group
Shortly after its formation, the Special Projects Group started researching vertical take-off and landing capability (VTOL) with emphasis on a paper study Frost had labelled the "pancake" engine, a jet turbine that had its main componets arranged in a circular design. From the outset, the Special Projects Group had a cloak-and-dagger feel to it. Housed in a Second World War-era structure, across from the company headquarters, the group had all the accoutrements of a top-secret operation, including security guards, locked doors and special pass cards. Within the confines of this technical fortress, Frost surrounded himself with a collection of like-minded dreamers and maverick engineers. There he encouraged close cooperation and, while ostensibly the boss, he was collegial and very much one of the boys.
[edit] Project Y
In 1952, the Avro Special Projects team began research and development work on a series of VTOL designs, known initially as "Project Y." The first of these proposed aircraft was a "spade-shaped" fighter intended to be powered by Frost’s revolutionary pancake engine. Named Project Y, this craft was designed to sit on its tail, and promised, in theory, at least, VTOL capabilities, climb rates to the tune of 100,000 feet per minute and speeds up to 1,500 mph. Project Y, funded by the company and the Canadian government, proceeded to the mock-up stage. By 1953, with the company having little more than a wooden mockup, paper drawings and promises to show for a $4-million (Cdn) outlay, a more critical eye was cast on the project. Not surprisingly, the plug got pulled when government funding from the Defence Research Board dried up.
[edit] U.S. Involvement
Frost wouldn't accept defeat; in addition to being a gifted designer, he was also a talented promoter and salesman. In late 1953, a group of U.S. defence experts visited Avro Canada to view the new CF-100 fighter jet. Somewhere along the way, Frost co-opted the tour and rerouted it to the Special Projects area where he proceeded to show off his mockup, models and drawings (some never before seen by senior company officials) for a completely circular disk-shaped aircraft known as "Project Y-2."
The USAF agreeing to take over funding for Frost's Special Projects Group and with American dollars rolling in, Project Y-2 received a new moniker -"Project 1794"- and a new lease on life. Frost and his team began pursuing a real flying saucer, one that would have advanced weapon systems and produce speeds in excess of Mach 2.
[edit] Birth of the Avrocar
A test model, powered by six Armstrong Siddeley Viper jet engines driving a central rotor, was built and housed inside a small, brick testing rig. Unfortunately, testing was anything but smooth. In fact, it was downright scary. The supersonic test model, PV-704 (PV stood for Private Venture), suffered from hazardous oil leaks, resulting in three fires. It eventually got to the point that staff were afraid of the machine, even when safely ensconced in a booth constructed of bullet-proof glass and quarter-inch-thick steel. A final, disastrous and nearly lethal engine test in 1956 which involved a Viper jet engine "running wild" convinced Frost that a less dangerous test vehicle was necessary.
Redesigning the supersonic platform to a simpler flying model led to the only design that materialized from the Avro Special Project Group, the VZ-9-AV Avrocar. The Avrocar was proposed as a proof-of-concept test vehicle for a later supersonic flying saucer design, the Weapon System 606A for the USAF, and, subsequently, was offered to the U.S. Army as a type of "Flying Jeep." Utilizing the Cook-Craigie system, two Avrocars were built on a production line, the first used in tethering testing before departing for wind-tunnel testing at NASA Ames and the other reserved for flight testing at the Malton plant.
Just as the first working test models were being manufactured, disaster struck. The Canadian government cancelled the Avro CF-105 Arrow program on "Black Friday," 20 February 1959. The ensuing result was the lay-off of almost all Avro Canada employees, including those with the Special Projects Group. However, three days following the announcement of the Arrow cancellation, many of the Special Projects employees were rehired and back in business. But it wasn't quite business as usual. The team now included people from the CF-100 and CF-105 teams and the Special Projects Group was moved into the main building, which was now nearly empty. As well, company brass became more involved in the group’s operations.
The USAF Project Office devoted to the Avro projects, recommended that the WS-606A and all related work (including the Avrocar) be cancelled. A “stop/go” work order came down and Frost was forced once more to try and rescue the project. In an elaborate effort, Frost laid out the design parameters of the vehicle and made a resounding case for continuation of U.S. military funding. Late in May 1959, the USAF authorized Avro to continue the “flying saucer” programs.
[edit] Testing
The Avrocar which ultimately appeared was a disc-shaped craft resembling those flying saucers popular in the movies of the period. Measuring 18 feet across by 7.7 feet high, it was designed for an empty weight of 3,000 pounds, with a crew of two (pilot and observer housed in opposite cockpits in clear, dome-shaped canopies). Power was supplied by three Continental J69-T-9 jet engines. Maximum speed was anticipated to be around 300 mph at an altitude of 10,000 ft with an estimated range of 79 miles. The thrust from the jet engines turned a central rotor, which, in turn, vented air through a series of vanes and ducts under the aircraft, thus propelling it and providing directional control.
The first free-flight test occurred on 12 November 1959. Additional tests were carried out in January 1960, and between July 1960 and June 1961, for a total of 75 hours. The results of the testing revealed a stability problem and insufficient performance due to turbo-rotor mechanical tolerances. The Avrocar was underpowered and could only operate safely in a ground-cushion effect, much like a hovercraft.
[edit] Cancellation
Before modifications could be achieved, funding ran out in March 1961. After Frost's proposals for a modified design were not accepted, the Avrocar and related supersonic VTOL programs were officially cancelled in December 1961 by the U.S. military. Avro company executives encouraged additional VTOL research projects, but no further interest resulted from Canadian or other sources, to cap the end to the Special Projects Group.
Judged by its performance, the Avrocar was an abject failure: it couldn't lift itself safely more than a few feet off the ground, and its bulbous design limiting high-speed performance accompanied by unbearable heat and screaming exhaust noise, made it impractical for the military. Although considered a technical failure, its design would be prophetic: it was a rubber skirt shy of being one of the world's first hovercraft, the Saunders Roe SR.N1 also taking off in 1959. Nevertheless, company designer, John Frost applied for a number of patents in Canada, the UK and the US that established the pivotal role that the Avrocar and related Avro experimental vehicles, made in the VTOL world.
[edit] Latest developments
The Avro VZ-9-AV Avrocar was a "dead end" in VTOL design, according to Rusell Lee, curator at the National Air and Space Museum, yet its technological innovations have intrigued other designers. One of the design elements it embodied, the use of ducted fans led to other experimental programs. Dr. Paul Moller, a Canadian expatriate who had worked at Avro Canada as a young engineer, based an initial series of experimental VTOL vehicles on "saucer" technology utilizing the buried ducted fan à la-Avrocar. The XM-2, the first of the series looked remarkably like a miniature flying saucer. After successful tether tests, the saucer designs also at one time publicised as "discojet" were abandoned and their latest project, the Moller Skycar, has a flying-car appearance.
The Avrocar story did not end with the termination of the program. Only two Avrocars were ever produced and because the U.S. military had paid for the work, they reverted to U.S. ownership at the end of the program. The second example, S/N 59-4975, utilized for "flight" testing, returned to Canada briefly for display in Montreal at the Man and His World Exhibition (1968); after a lengthy period of outdoor display, it is now under restoration at the U.S. Army Transportation Museum in Fort Eustis, Virginia.
The first Avrocar, S/N 58-7055 (marked AV-7055), after tethered testing, became the "wind-tunnel" test model at NASA Ames, where it remained in storage from 1961 until 1966, when it was donated to the National Air and Space Museum, Washington, D.C. Originally scheduled for display at the newly constructed Steven F. Udvar-Hazy Center, located at the Washington Dulles International Airport, a long-term lease arrrangement is being undertaken to bring this example back to Canada. The Toronto Aerospace Museum will restore and display the Avrocar as part of an Avro Canada display collection.
A full-scale replica of the Avrocar was prepared for the 2002 production, Avrocar: Saucer Secrets from the Past. It now resides as an exhibit at the Western Canada Aviation Museum, Winnipeg, Manitoba, Canada.
[edit] Further reading and viewing
- Avrocar: Saucer Secrets from the Past. Winnipeg: MidCanada Entertainment, 2002. <http://www.avrocar.com/>
- Zuk, Bill. Avrocar: Canada's Flying Saucer... Erin, Ontario: Boston Mills Press, 2001. ISBN 1-55046-359-4.
- Zuk, Bill. The Avrocar Story.<http://www.avrocar.com/avrocarstory.html>
