See subject: Champagne cork forces easyJet plane to make emergency landing
Champagne pressure and velocity discussed here: Can you be killed by a champagne cork?
I’m guessing the blown out ceiling tiles caused a change in cabin air pressure and the masks fell as a result.
I don’t see where it says they ALL dropped. The units are sometimes not held very securely and a mild knock may make one set drop.
Reading further I see it was just the cabin crew masks that dropped. So probably a combination of the ceiling panel clips being a bit worn plus a knock from the cork to drop them.
Two issues:
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Cabin pressure is contained by the outer cylindrical hull of the aircraft, not the cosmetic ceiling tiles lining the interior of the cabin.
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Richard Pearse will know for sure, but my understanding is that the oxygen masks for cabin occupants are deployed by a pilot-operated control (and not in automatic response to a loss of cabin pressure).
Correct, so a pooped cork will have no affect on the cabin pressure.
Incorrect, it is an automatic system with a manual backup on modern types. All the pilots should have to do is confirm the system has worked.
Aside: You know you’ve done a bad landing when you have to call the engineers in to stow the cabin O2 masks.
:smack:
I apologize. I was half asleep…
It’s bad to do that in an OP.
Ignorance fought; thanks.
Where are the pressure sensors located?
If you gave one of those a whack, the resulting signal spike might have consequences.
Presumably there are multiple sensors, and a polling system to come up with a consensus value, but this is an airplane, not a spacecraft. The builders might have gone for cheap and paranoid instead.
Cabin pressure, no. Cabin atmosphere, probably. Unless it were in the lavatory. 
Sorry, the mental visual was so absurd I had to comment.
Yeah, if someone on a plane with me poops a cork, you can be damn sure I’ll be looking around for an oxygen mask.
Need answer fast?
The typical installation has dual identical pressurization controllers. One is live and one is backup. Either manually or automatically we alternate between them from one flight to the next. If either one detects an internal fault it immediately hands off to the other. If we suspect something hinky with the active unit that it didn’t detect we can force a handoff. There is no voting because there are only two. There is also a backup manual system we can switch to if both auto systems go stupid. You’d rather we not use; it *will *be hard on everyone’s ears. 
The pressure transducers and brain boxes are buried in the bowels of the aircraft someplace. Not a place subject to errant corks. Unlike back in the 70s, this modern stuff is uber reliable and uber smooth.
Back to the OP: Those overhead compartments are built lightly. The latch is a very simple beveled lock bolt that fits into a solenoid operated latch. Except for the electric part, it’s about as sophisticated as the latch on a ladies’ purse. The door itself is flimsy but very expensive fire-retardant non-smoking plastic. A good whack on the door may pop the latch loose. At which point the door flops open on its hinges exposing the compartment holding the oxygen generator canister, the masks & hoses, and the tennis-ball sized dust bunny lurking in there.
Which dust bunny(ies) will stink to high heaven if we ever do deploy the oxygen for real & folks fire those chemical generators. They leave that part off the demo for some reason.
400 to 780 hPA in a matter of seconds, does sound painful.
Nice cite/data.
I’ve got my own barometer hooked to an Arduino, but I figure the TSA would have a fit if they ever saw it. I’d like to have sub-second level data on how steady they keep the pressure at cruise altitude.
I’m not seeing those numbers in there, going blind?
Me neither.
Once in level flight the intent is to maintain a constant cabin altitude = pressure. Given that cruise flight also involves an almost fixed power setting, the controller doesn’t have to try very hard to maintain a constant output given almost perfecly constant inputs.
I expect the control system has a deadband to prevent hunting. So given enough precision you’d probably see a slow random wander with some bias towards high or low. And when the deadband is eventually exceeded by the accumulated bias you’d see a distinct control input to drive the results relatively quickly back to the target.
My ears can feel 100 feet per minute which is a pretty gradual change. Our cabin altimeter gauge is small and not tightly marked. But we don’t see it moving detectably during cruise. Which I’d WAG at it maintaining +/-100 feet for hours. I just don’t see or feel pressures or pressure changes other than dead-steady with modern aircraft.
Meaning your ears don’t pop?
You know, I didn’t either, but I figured it was something sciency I was missing and didn’t want to bring it up. I wish I could say there’s a moral there, but there isn’t.