The story of Avro's experimental "flying saucer", the Avrocar. It was the result of Avro's research into vertical takeoff and landing (VTOL) aircraft. Research and development started in the mid 1950s but development was cancelled in 1961 after flight stability problems could not be overcome. Rare footage include: design and construction of the craft, wind tunnel tests, and many of its tethered and free flight tests. Helivector - A one-man amphibious helicopter the DH-4 Helivector, could be flown by a novice and featured two, 15 foot diameter counter rotating blades.