It was called Spymaker and starred Jason Connery – I remember it! I also recall Bamburgh Castle in Northumberland was used for the assault sequence but I don’t remember the aircraft sequence !

TT

Yes that’s the one, and I wondered which castle it was. Bamburgh being one of the few in the area which we haven’t visited.

The glimpse of the aircraft come near the end, when he comes back from the commando raid, and jumps out of the DC-3.
I didn’t see anything on the credits.