Didn't Airfix share tooling with Matchbox? If so ,I've got a 1/72 B-17G ( Matchbox packaging) that comes with 4 very rigidly posed crewmen,all identical,sitting with their hands on their outer thighs. I won't be using them,I'm sure.
If you are talking about the ones that came in the kit I seem to remember they were moulded in silver plastic and you got two pilots, a bomb aimer lying prone,and gunners for the ball turret,waist guns and tail.
They all had oxygen masks on and the bomb aimer resembled an egyptian mummy!
If however you are talking about ground crew then you're in luck as Airfix have just re-released the USAAF Personnel set.