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This has to be a first. There's a nutjob for everything. Apparently, when the door is armed below differential pressure altitude, it's do-able...
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Happened at 250m agl apparently. Worrying.Originally posted by Evan View Post
Asiana Airlines: Passenger arrested for opening plane door during South Korea flight - BBC News
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I wonder why the slide didn't deploy (thank god!).
Or did it?!!Comment
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There are a lot of comments about how the slipstream force at 150kts would make it impossible to open the door. But I assume the cabin air pressure is actually greater than that along the outer fuselage due to the Bernouli principle (Gabriel might reward this assumption with many, many words). But the door must also move forward against the slipstream. The door mechanism has a pneumatic power assist that obviously did the job.
I assume this plane didn't land with the slide wrapped around the empennage. So... what became of it...Comment
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No.Originally posted by Evan View Post
Yes.(Gabriel might reward this assumption with many, many words)
1- Bernoulli only applies to 2 parcels of air on the same streamline (and about a dozen other requirements that are not interesting here).
2- A parcel of air inside the fuselage is not in the same streamline as a parcel of air flowing along the outer fuselage.
3- Before you ask then how can Bernoulli be used to explain lift (air below the airfoil goes slower and has a greater pressure, air above the airfoil goes faster and has a smaller pressure), it is indirect. What you are doing, technically, is compare the speed and pressure (i.e. the energy) of a parcel of air above or below the airfoil with a parcel of air in the same streamline far ahead of the airfoil (undisturbed air), and then compare these 2 parcels far ahead (one corresponding to the streamline that goes above and one with the streamline that goes below the streamline). These 2 parcels have the same energy because they are parcels of undisturbed air next to each other so they have the same speed and pressure. In other words, if we call ET0 and ET1 the energies of 2 parcels of air on the same streamline above the fuselage, with ET0 being far ahead and ET1 being just on top of the airfoil, and we do the same with EL0 and EL1 for the airstream below the airfoil, what we do is:
ET0 = ET1 (by Bernoulli)
EL0 = EL1 (by Bernoulli)
ET0 = EL0 (NOT by Bernoulli)
Therefore, ET1 = EL1 and you can kind of apply Bernoulli between these 2 parcels.
But you cannot use the 3rd equation between a parcel of air inside the fuselage and a parcel of air flowing along the outer fuselage, and therefore you cannot apply this "kind of" Bernoulli between these 2 parcels of air.
4- Google "alternate static pressure source" (it applies to unpressurized planes)
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I am surprised that the system doesn't have safeguards (conditions that need to be met) against intentional or accidental opening in flight even in an unpressurized condition.
I know that the 737NG and MAX overwing exists do.
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Asiana Airlines suspends sale of emergency exit seats (26A and 31A) on A321-200 aircraft
Asiana Airlines to stop selling seats near emergency exit on Airbus A321s | CNNComment
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It did. Add it was ripped off (thank god!)Originally posted by Evan View Post
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