b737ng pressurisation
hello alexban,
in your scenario, you really have a bad day.
but,firstly, the b737ng has no ecam( electronic crew alerting messages).
and this is some kind of a problem for companies using the new boeing standard operating procedures,(sops), because these new procedures are now in line with other more advanced boeing models like the b777, which have the full ecam capability. by this i mean, the checklists are reduced to an absolute minimum(only safety critical items remain) & are common to more than one type of aircraft, which in itself is ok. but for the b777 these checklists have the back up of a full ecam system, whereas the b737ng has no such back up.
now, back to your original scenario. it's more or less the same situation as proposed by gotabefun: left bleed trip off with no reset possible, the checklist ask you to switch left pack off in order to have the right pack go into high flow, in flight, with the flaps up. if now that right pack trips off, also with no reset, then there is again no need to have the left pack off. so here once more some quick thinking & system knowledge are required : engine n°2 feed the left pack through the isolation valve.
for the smoke scenario, always first go in full protection mode(mask/goggles or full face mask) on oxygen & establish communication. then determine smoke origin(airco or electrical) & follow qrh accordingly, eventually followed by a smoke evacuation procedure & get the bird on the ground asap.
hope this explanation helps.