CargoOne:
Thanks for the comment on costs, although it's worth noting that at Stansted, it seems fairly common to have the aircraft parked adjacent to a bridge but still use stairs. I had other things on my mind last time (stairs and 1.5 sprained ankles don't mix) but I have vague recollection that the Ryanair 737 has its own stairs, at least at the front. Presumably that's even more of a saving in running costs, just pax on the tarmac and hold the door open at the base of the bridge.