Originally Posted by
sonicbum
I believe a bang seat is a seat that emits a "bang" if you pull a specific handle or it could also be a seat that helps you "bang" by telling your war stories to ladies (or gents depending on taste).
The cockpit seats on some Fokker 50s made a sort of bang sound when the adjustment lever was used. Can't 'member a mask attached.
Maybe more of a crunch or creak though, it has been a while ago...