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jgoggi

Pressurization-oxygen

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Hi,I have ver. 1.1 and a couple of questions:1. I am cruising say at 39000 ft: I open the doors and I don't get a cabin altitude warning, and the cabin rate of climb remains zero! How is that possible??2. I don't see any oxygen quantity indication on the EICAS. Where are they??Thank you,James


James Goggi

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Sorry, I forgot to say that it's the 747-400.


James Goggi

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"1. I am cruising say at 39000 ft: I open the doors and I don't get a cabin altitude warning, and the cabin rate of climb remains zero! How is that possible??"James.... Maybe you should ask... "How is it possible to get my doors open at 39,000'? :)Cheers.Q.

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Yes, Mr. Q (IR for fiends? :-)), but this makes me think that the pressurization system is not well modelled. If on another Boeing two-engines addon (like VH-OGE, for example... ;-)) I open the doors during cruise, it becomes a Christmas tree with lights and warnings everywhere, the cabin altitude suddenly shoots up and the oxygen masks drop...Cheers!


James Goggi

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The point is that you can't open doors at 39,000ft while the plane is pressurised. So even if you wanted to, it is impossible to open the door inflight - so why model a decompression that doesn't happen in real life? I'd imagine this is reasoning behind not modelling decompression for this situation, although I could be wrong.CheersRudy


Rudy Fidao

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Guest Ray51

at that altitude the differantal pressure is somewhere near 8 lbs per square inch. A 10 by 10 inch "door" would require 800 lbs. of force to open inward like aircraft doors do. I think only the "Russians" have cabin attendants strong enough to open those doors! LOLRay

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what about a "normal" decompression? meaning, decompression through other means besides the door. is it modelled on the 747?tomo


Tom James

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I thought it was possible to open the door in flight to aid with smoke removal from the cabin. Saying that though, I am not aware of the altitudes involved or the cabin pressure.


Alaister Kay

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"I thought it was possible to open the door in flight to aid with smoke removal from the cabin."Only if the aircraft descends to 10,000' and depressurizes the cabin manually. Pack airflow and (maybe) venturi effect is sufficient to extract smoke from the cabin.On a full sized cabin door at 8 psi differential pressure, you'd have something like 20,000 lbs pressure keeping the door closed.Having said that, one RW pilot on the PMDG team thinks he could crack the door at full differential pressure.Personally, I think you would break the aluminium handle or door opening mechanism before that happened. Neither of us is willing to attempt this, however :(Cheers.Q.

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Guest D17S

Aw come on, somebody try. The old DC8s I work with have a main entry door lanyard that allows the crew to open the door (airborne) and peak out with a big ol' flashlight/lantern to shine back on the wing. It's a freighter and it's the way they check(ed)for wing ice at FLXYZ. Can you imagine? When we installed this bazar system 10 years ago, we all just smiled. Just when you think you've seen it all . . . Here's the drill. Depresurize at FLXYZ. (No folks. The door will not open pressurized. That's been tried, but that's another story.) Everyone on O2 as the poor ol' PFE bundles up with the portable O2 bottle and cracks the door, ties it off, jambs it open with something,(like the hot cup, maybe?) then leans out of the door with this flashlight to check for ice in the wing leading edge? They couldn't imagine it either, so it seems. Unbelievable?: But a true story. About a year ago we finally took the lanterns out . . . guess there weren't many takers.

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Well the procedure to deal with one is in the manual so it seems likely it's modelled. Going on another logical tack, if opening the door triggers a depressurisation event, then PMDG have obviously modelled that event, and I doubt they programmed such a feature solely for those who open doors at FL390! :-)Next person rostered on a PMDG 744 flight, check the failures menu and see if it's in there!


Mark Adeane - NZWN
Boeing777_Banner_BetaTeam.jpg

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Cheers, I thought there must be some sort of descent and depressurisation :-)


Alaister Kay

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>Only if the aircraft descends to 10,000' and depressurizes the>cabin manually. Pack airflow and (maybe) venturi effect is>sufficient to extract smoke from the cabin.I recall this hijacking/heist accident over US somewhere in Oregon where this guy ended up with a bag full of money that was paid to himn as a ransom (I don't recall details) and he ordered pilots to fly this 727 somehwere over Utah, told them to descend to 10000, to depressurize the cabin, to slow down to their minimum speed, opened the rear airstair and parachuted out of the aircraft. I think there was even a movie made about this whole story. Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg


Michael J.

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