What type and make of airplanes?
What unusual planes in this movie?
shareThe test plane was an Airspeed AS.6 Envoy. See:
https://en.wikipedia.org/wiki/Airspeed_Envoy
I noted that odd biplane airliner that delivered Richardson to the factory was marked G-AENN. I looked it up and that was a De Havilland DH89A Dragon Rapide. A totally new airplane to me. That is I'm sure I'd seen then in other films but had no idea what the aircraft was called.
https://en.wikipedia.org/wiki/De_Havilland_Dragon_Rapide
The small biplanes are of course the more common Tiger Moth.