High altitude decompression from bullet hole

Hypothetical:

The United States, in a reversal of previous approaches to airline security, decides to require that all adult commercial airline passengers who are registered firearms owners be armed with .22 caliber pistols issued by the airline.

On one of the flights, a giant sentient squid arises from its seat and announces, “This is a hijacking! Please stay calm!” Four passengers instantly fire at the Giant Squid. Three of the shots wound him. But one misses wildly above his head and pierces the fuselage.

Does the plane explode?

No.

Not only does it not explode, but you probably wouldn’t even notice, except for the whistling sound of air pressure bleeding out of the hole, and then only at high altitude. Although airliners are pressurized for the comfort and safety of passengers at high altitudes, the pressure adds nothing to the structural rigidity of the airframe. Nor is anyone going to get sucked out of a .224 inch hole. Popping out a window would be more disconcerting, but the pressure difference isn’t enough to suck someone out a la Goldfinger. (“Where’s Goldfinger?” “Playing his golden harp.”)

It wouldn’t it make the plane uncontrollable, either, although losing a substantial amount of the fuselage skin might make the ride more turbulent; at that point, however, I don’t think the passengers would notice much, being more concerned with exposure to thin, cold air and high wind speeds. As an aside, I was watching Goldfinger the other day, and not only do they perpetuate the notion that a punctured fuselage will cause the plane to fly out of control, but they also have a car blow up as soon as it flies off a cliff, long before it actually hits anything. Ah, movie physics…it’s better than a Warner Brothers cartoon.

The biggest dangers from someone firing a gun at a squid on an airplane is (a) shooting another passenger in the tight confines of the cabin, (b) shooting a control wire, hydraulic line, or puncturing a fuel tank, or (c) shooting the squid only to discover that it is actually the Great Cthulhu, and as and Elder God he doesn’t appreciate being shot at by puny humans.

Stranger

Source: http://mythbustersresults.com/ (Episode 10)

In fact, a modern airliner can loose a great deal of its fuselage and still be airworthy.

(That’s Aloha Airlines flight 243, BTW, shortly after its emergency landing. There was only one fatality.)

One incident of note is Aloha Airlines Flight 243, which suffered an explosive decompression due to metal fatigue. The entire top of the cabin from just behind the cockpit to the wings was torn off. One flight attendant was sucked out. Despite this, the pilot was able to maintain control and make an emergency landing with no other fatalities.

And *that *is why I obey the Captain when he tells me to put on my seat belt!

I watched Snakes on a Plane, and they pulled this stutn - trying to decompressurize the cabin. I was jumping up and down, shouting “No way! I saw it on Mythbusters! They can’t do thaT!”

That was the part that had you jumping up and down?

And a good-sized dry cleaning bill, I would wager…

Frangible bullets in the OP’s scenario would prevent even a non-explosive decompression.

Meh; even a frangible bullet would likely penetrate the thin aluminum skin of an aircraft if fired directly at it. The benefit of frangibles is that they tend to break up on impact, so overpenetration or ricochet is less likely.

Stranger

.22 cal? Sub sonic 9mm or rubber bullets would probably be more effective and less dangerous on a plane. That being said it IS your hypothetical so who am I to criticize?

Right, you would want something along the lines of a dum-dum.

It depends on just how big the hole is and just where it is. On the right plane, a big enough hole in just the wrong place and you get a plane crash.

Does this sentient squid’s name rhyme with Zulu? Because if that’s the case, then I think an exploding plane is the least of humanity’s worries.

Does this sentient squid’s name rhyme with Zulu? Because if that’s the case, then I think an exploding plane are the least of humanity’s worries.

I saw a show on this incident. One of the theories as to why the damage was so great revolves around the missing flight attendent.

Aircraft skins are reinforced with antirip mesh, about 10"x10" squares. This means that a puncture in the outer skin should not rip too far. The Aloha Airlines plane ripped open far more than that. The theory was that a hole blew out and opened up a 10"x10" hole - explosive decompression. All the air in the plane starts moving towards the hole, building up momentum. The flight attendent was sucked into the hole, and jammed/plugged it. This created an air-hammer pressure wave in the plane focussed around the weak point of the skin (with corrosion and metal fatigue issues), and a huge hole blows out. 600mph air pressure and ripping does the rest.

Si

I had to sit next to a giant squid on an eight hour flight once; tentacles everywhere - all across the armrest. Cephalopods above a certain size should be made to purchase two seats.

I thought that they used low charge cartridges.

Once I inadvertently got sight of the weopons collection on an aircraft at Heathrow, the UK police were inspecting them with enthusiastic interest. They did not look like Saturday night specials I’m no expert on these things but they looked like short barreled .33 revolvers.