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Only if the aircraft in question is being flown by Miss Pussy Galore, and has Bond, James Bond on board ....
Remember that scene in "US Marshals" when that convict puts together a gun in the toilet and tries to off Wesley Snipes?
I imagine explosive decompression would probably be something like that.
Boeing Country: Guns in jets: Don't believe movie imageJetliner cabins are pressurized. The air inside is compressed to the same density as air at 8,000 feet of altitude. Airliner fuselages at 30,000 feet frequently are compared by the press to inflated balloons. The implication is if you puncture it, it will blow.
That's plain wrong. First, the difference in pressure between the inside and outside air at 40,000 feet is 8.6 pounds per square inch, and the cabin wall is tested to withstand 18.2 pounds, more than twice as much. Second, airliner fuselages are not airtight -- they leak air all the time.
Maintenance people told me that in the days when smoking was allowed, you could find leaks in the fuselage simply by noting the starting point of the brown streaks of cigarette tar.
One engineer told me that Boeing pressurizes each new plane to look for and seal leaks. If the plane passes this ``low blow'' test, it's subjected to a ``high blow'' test at even higher pressure to proof the fuselage for pressure changes.
During the tests, assembly workers outside feel for leaks. When they find one, workers inside apply a sealant glue that is sucked into the leak and seals it. But here's the key point, he said: They don't necessarily have to find all leaks; they just have to find enough.
The cabin atmosphere is continuously pressurized using air from the engines' compressor stages, cooled and mixed with cabin air. The pressure is controlled automatically. If it needs to be increased, more is drawn from the engine. If it needs to be decreased, an outlet valve opens to draw out cabin pressure.
And -- talk about holes in the fuselage -- a retired airline captain told me that the outlet pipe may be 15 inches in diameter, though it's rarely opened fully.
In a twin-engine plane, there are two sources for the compressed ``bleed air,'' and with that air at 40 pounds per square inch, the engines are capable of supplying far more air than they ordinarily have to.
So if a small hole -- say bullet-sized -- opened in the fuselage, the air conditioning packs would supply more bleed air, easily keeping up with the air loss. ``All you'd have is a whistling noise in the cabin,'' a structural repair specialist said It would be no worse than when you open the lavatory sink drain or flush the vacuum toilet.
The oxygen masks, which drop from the ceiling automatically when the cabin air pressure drops below about 12,000 feet, wouldn't even deploy.
But wouldn't the air rushing out open the bullet hole further?
Only in the movies, the structural guy indicated. All jetliners incorporate ``tear straps'' in the fuselage wall. If a hairline crack or bullet hole opened in the skin and started to grow, it couldn't progress far before it reached one of these reinforced points and turned, making what he called a ``controlled flap.''
OK. But what if the slipstream catches a projecting piece of the plane's skin torn out by a bullet? Wouldn't that pull more metal away?
Possibly, but again, not as it does in the movies. A Boeing engineer told me that at 400 knots, the air passing over the plane exerts only 4.11 pounds of pressure per square inch. At 450 knots, it's 5.33 pounds. So if a bullet opened a 4-square-inch projection outside, the slipstream would exert about 21 pounds of pull on it.
``I have no problem at all ... If you shot 50 holes in the fuselage, structurally it would be no problem at all,'' the structural expert said.
That is highly unlikely.
Remember the plane in Hawaii a few years ago that lost a large piece of the fusilage and the pilot managed to fly it and land it with the only fatality being someone who was sucked out through the gaping hole.
Bullet holes would cause decompression, but not likely cause catastrophic failure.
A greater danger would be if a bullet punctured a hydraulic line causing loss of control.
"At altitude? Not much. The first round to penetrate the fuselage would probably cause an explosive decompression that would not only suck people out the hole, it could cause enough damage to bring about catastrophic failure of the fuselage."
...and you got your facts from what movie???
Do you really suppose there is such a shortage of stupidity and ignorance in the world that it is really necessary for you to come here and spread yours around?
Urban myth.
Passing on an urban myth as fact is always a bad idea, regardless of who is tellin it or to whom.
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You watch too many movies.
You won't get explosive decompression and no one will get sucked out of any holes.
I've read that the urban myth of explosive decompression has been exposed in recent tests. Bullets that penetrate the fuselage just cause the hissing air to escape like opening the valve on a tire. Two things to keep in mind:
1. Even at FL410, there is atmosphere; little oxygen and cold, but not a vacuum.
2. The cabin is pressurized but not sealed; it is constantly losing pressure as the air compressors compensate.
You probably shouldn't comment on things when you have absolutely no clue what you're talking about.
I suggest, either do some studying or don't post so strenuously about subject which you are not qualified.
So you are against Air Marshalls or other feds carrying?
I'm pretty sure that Air Marshalls have safety slugs. They disintegrate on impact.
Besides, if you've ever been through heavy turbulence, you know those air frames are built tough. IMHO, simple air flowing out of the plane from a bullet hole isn't going to do a thing.
If a bullet were to penetrate a pressurized airplane, the passengers would not be sucked out the windows from "explosive decompression." That is a persistent urban myth originating with the 1964 movie, Goldfinger, starring Sean Connery as James Bond.
Airplanes already have holes. Air is constantly pumped into... and out of... the plane. (Otherwise, the passengers would suffocate.) It is not a closed system. The size of the hole (the "outflow valve") depends on the size of the plane, but it is a big hole. Outflow valves are over a square foot on the 737, up to two square feet on the 757, and so on. You can lose three windows and still keep the cabin pressurized. A 9mm/.357 caliber bullet makes a hole with an area of 1/10th of a square inch. (Area = pi R squared.) The effect of a bullet hole on cabin pressure is not enough to be measurable.
Explosive decompression only occurs with huge holes. In 1986, a bomb blew a 20-square-foot hole in a TWA 727 over Athens, and 4 passengers were killed. In 1988, an 18-foot section of the roof came off an Aloha Airlines 737 mid-flight, and one flight attendant was killed. (Both planes landed safely.)
If the Goldfinger Syndrome were true, the Airline Pilots Association would not have voted to arm pilots, and the FAA would not be talking about armed sky marshals.
It's a myth, OK? It was just a movie.