Apparently we didn't need them 'cos "Lads, the pressure will hold the top door closed". As long as the pressure stays in there, that is. What happened to mechanical back-ups? Then the bell btm door stuck, then it leaked, then it stuck so we took cover of & levered the fkr to break the fantastic new-fangled fkn double lip fkn seal, which stuck again on next run. Then leaked. ok, I'll sit here reading me book, the Techs can deal with it. That fkn bell spent more time on surface than I did on that trip.