alexban: "I don't think you can achieve bellow 22000' a ROD of 8000',maybe if you lower the gear,but I guess it won't be achievable.I'll try it next time on the sim.You actually do this on sim?"
: Nope. We haven't done this particular profile on the sim. But on our regular depressurization drill we are averaging about 2500 to 3000fpm i think. (I am trying to get a more accurate figure from our sim instructors or maybe at my next sim ride). But I felt the same: 8000fpm does seem rather optimistic.
Flight Detent: "If someone wanted to fine tune this extremly improbable case I would suggest investing in more detailed maps to get you out of FL220 sooner."
: Our performance department has managed to get hold of some pretty accurate topographical maps of the region(crtsy the Military). The problem is that the grid MORA in the region is 25400ft. So the flight path to follow in case of a depressurization is defined, and the path crosses a peak of height 21370ft. We are supposed to be 22000ft there. Infact which brings up the question whether we need to clear mountainous terrain by 2000 ft in case of an emergency descent as well? I'm personally thinking that we need to probably install 22mnts of O2 capacity which would permit a higher intermediate level-off altitude.
alexban: "I think there could be some cases when you won't have structural damage:for ex dual bleed trip off (very remote ,i think) ,malfunction of the pressurization system ,of the outflow valve..."
: In case of a dual bleed trip the actual rate of cabin climb is just about 500-600fpm in a new aircraft(delivery testing at boeing) and maybe 1000fpm in case of older aircraft- not much more (hopefully )
Reasons for rapid depressurization without structural failure : Window failure. Outflow valve failure to open position in flight. Any more thoughts?
Rainboe: Great job done
All: thanks for your thoughts.
Many happy landings.....