In 1958 Avro Aircraft ltd. (Canada) introduced a concept for a vertical takeoff and landing craft that would be undertaken as secret U.S. military project. This project, directed by John Frost, was a Cold War era attempt at creating a flying saucer for military use.

It was originally designed to fly very high speeds and altitudes. The project was repeatedly cut for funding, personnel and materials, and was eventually abandoned by the U.S. Air Force. Later it was taken up by the U.S. Army as a fighter craft.

It's main issues were with stability, direction and thrust; degrading it to a low performance flight disc. It used a theory called the coanda effect which limited it to nearby surfaces.

Frost thought that in order to make such a vehicles, they would have to make smaller "test vehicles", which led to the army making a flying jeep of sorts. The first performance requisites for the Avrocar were a 10 minute hover capability along the ground and 25-mile (40 km) range with a 1,000 lb (450 kg) payload.

U.S. Army Avrocars depicted as "flying jeeps" in company literature.

The new plan appeared to make everybody happy, and a $2 million joint-services contract managed by the Air Force was awarded to Avro to build and test two Avrocars, which the Army referred to as the VZ-9-AV (with AV standing for "Avro," an unusual departure from normal U.S. Army nomenclature[17]), the latest in a series of "VZ" aircraft. Army interest in the Avrocar program was apparently very high. Bernard Lindenbaum of the Air Force Flight Dynamics Laboratory recalls a trip to Washington in the late 1950s to request additional funding for a study on helicopter drag reduction. Although the funding was approved, he overheard an Army General remark that theHuey would be the last helicopter the Army would buy since the helicopter would be replaced by the Avrocar.[15]

Additional Air Force funding of approximately $700,000 (unexpended from the 606A program) was also moved to the Avrocar project. In March 1959, an additional $1.77 million contract was received for a second prototype. At rollout, projected performance was far in excess of the requirement, with a 225 knots (417 km/h) maximum speed, 10,000 feet (3,000 m) ceiling, 130-mile (209 km) range with 1,000 lb (450 kg) payload, and hover out of ground effect with 2,428 lb (1,101 kg) payload. Maximum takeoff weight with transition to forward flight out of ground effect was calculated to be 5,650 lb (2,560 kg), maximum weight with a transition in ground effect (GETOL) was 6,970 lb (3,160 kg).[15]

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. 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 nearly empty. As well, company "brass" became more involved in the group’s operations.[18]

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"[19] work order came down and Frost was forced once more to try to rescue the project. In an elaborate effort, Frost 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.[20]