PercyWhino's detailed explanation is excellent. I think I've got it now! Many thanks.
Yes I agree about the gangway of the Jetstream being something of an obstacle course. Until I saw the spar running across the floor I couldn't figure-out why that red "CAUTION" light seemed to be permanently illuminated on the ceiling above the obstruction. It makes you look up - just at the point you should be looking down.
Apart from that single door at the rear on the port side, if memory serves there was only one other exit - and over-wing removeable panel on the starboard side of the aircraft. I suppose, in the event of a fire on the port side, everyone could get out through that starboard exit - but it might take a while....
Anyway thanks again PercyWhino and everyone for their most useful advice.
Last edited by korrol; 8th August 2011 at 11:13.