Avro, Inc. This Canadian company put the pedal to the metal in designing a real, working jet-powered UFO: the AvroCar.
Profile on Display A shot of the Avrocar on display in a museum -- Bill Zuk, Avro historian is shown in the foreground.
John Frost, Engineer The man in charge of developing the AvroCar, during a rare interview with the media about the project!
AvroCar Closeup Check out this large-scale photo of the Avrocar, shot from above to show the fan intake and coanda-effect hull.
AvroCar Cutaway This cutaway schematic shows the interior layout of the AvroCar, incuding the interior layout of the jet turbines.

The AvroCar was a collaborative effort to develop a saucer-shaped vehicle capable of VTOL flight. The craft was built by the Canadian Avro Corporation under funding from the US Army and US Air Force.

Avro-Action

The breakthrough British TV documentary "Secrets of the Saucermen" describes the AvroCar as a first-generation hovercraft developed to showcase technologies being developed for a larger UFO shaped craft. However, in 1953 the Canadian Minister of Defense Productions claimed that the AvroCar could fly at nearly Mach 2 and climb to any height.

Avro UFO Prototype 2

After limited success with the first-generation AvroCar, the Avro Corporation began construction on a larger, six-engine vehicle, shown in the above photographs. This larger prototype also had the unmistakable UFO shape, and was based on Coanda-effect lift. The six engine vehicle reportedly encountered a critical engine failure during testing, which set back development. During this delay, Avro went bankrupt due to unrelated business issues, and development was halted.

Editor's Notes

In all of the photos above, the Avrocar is shown hovering only a few feet above the ground, yet it's been presumed that a final production-model AvroCar would be capable of flight comparable that from UFO reports of the day. Perhaps the saucer shape puts the comparison immediately into people's mind -- or the idea that the government would fund a "flying saucer" only to instead build some new type of hovercraft.

The AvroCar certainly had the power for full-fledged flight -- the test-prototype had two turbine-engines working in tandem to spin a large central fan, and the never-completed larger-scale prototype had a total of six full-size jet engines. Wasting this kind of power for only some type of hovercraft would seem to be a waste of potential.

John Frost's media comment was rather vague, though -- his interview response indicated "jumping over hedges, fences, and small obstacles like trees". Was he being evasive, or was he simply indicating that the Avrocar technology was either not powerful enough or stable enough to fly other than as a ground-effects vehicle.

Videotape of tethered tests and later accounts from the engineering team seem to show that the AvroCar was very unstable in a steady, motionless-hovering position. This makes sense, as it is the same challenge of "air-pileup" to be solved in the 1990s - not the 50s -- by Jack Jones Geobat design.

Ordinary hovercraft lack the upward propulsive force to actually become unstable -- they only stay off the ground by filling a rubber plenum, which by its very nature leaks air out the bottom in a stable manner. Hence, a traditional hovercraft doesn't have enough horsepower to get it in trouble, and the weight of the plenum assists with keeping it stable and upright.

The AvroCar has no plenum, though -- but does have large engines and power-output comparable to a jet-fighter. When the Coanda-Effect lifts the craft off the ground, a curtain of air is formed under the saucer, which creates a high-pressure area that the AvroCar will tend to slide off to maintain stable pressure underneath. Hence, in a standing-mode operation, the AvroCar literally "slides around" on top of its air-cushion, leading to an unstable hover.

The best comparison for this aerodynamic effect is the frisbee, which will also tend to skew to one side or another during flight. However, this problem is not unsolvable -- even in the frisbee world. The introduction of the ring-shaped frisbee allows pressure from the airfoil's center to flow up through the middle, while still maintain lift around the ring. In a similar manner, Jack Jones Geobat design allows a saucer-shaped craft to become more stable during flight (although his didn't spin).

Over the last several decades, the US Military has experimented with a number of saucer-shaped designs, and abandoned all of them because of inherent aerodynamic instability. However, the vast majority of UFO reports (especially those from earlier eras) show a circular disk shape -- so how can those designs overcome aerodynamic instability?