Most of the test flying at that time was still done by Captain de Havilland himself, but presently the company engaged a second pilot.
Having tested some of the early jet aircraft, he retired from test flying in 1948, becoming a sales executive for Hawker.
After spending almost ten years working for the Saunders-Roe company, he was killed in 1958 while test flying the SR.53, an experimental interceptor.
After 700 hours of test flying it was decided to introduce the following changes to the production planes:
Raynham did much of the test and development flying on the Avro 504.
While the prototype was test flying to gain certification the programme was abandoned.
He retired from test flying in 1987, having flown over 6,000 hours.
Stephens did most of the experimental test flying in the two-year test program.
It was damaged during ground-running due to incorrect control phasing arising from a high order of pitch-flap coupling, and did not start test flying until 1945.
The ensuing investigations and rectification of the flaws delayed test flying by several months, resuming in December 1993.