New Dual-Control Delta In Flight -- Here's the first in-flight picture of Britain's new dual-control, Avro (A.V. Roe) delta-wing 707C Research plane. The first flight was made July 1, from Waddington airfield at Lincoln near the A.V. Roe works. The 707C Powered by a Rolls Royce derwent engine, is designed to assist pilots in flight familiarization with with deltas, hence the dual control. At the controls for the first flight was squadron leader J.B. Wales, OBE, DFC, TD, AVRO test pilot. July 1,