What will happen to pressurised aircraft flying at 8,000ft with a bullet hole in it?

Answer 1

Basically, nothing will happen. At 8,000 feet, the pressure differential in a pressurized aircraft is minimal, with cabin pressure usually set for something around 6,000 - 8,000 feet (and never below the altitude of the airport of intended landing). A slight increase in cabin altitude (the effective altitude of the cabin under pressurization) is possible if the leak is large enough to overcome the in-flow rate capacity of the aircraft's pressurization system, but cabin altitude will be no higher than the aircraft's actual altitude. The movie/TV scenario of a small hole (such as a bullet hole) causing a huge tear in the aircraft's skin, people and objects being sucked out of the aircraft (usually with tremendous force), and loss of control of the aircraft itself, are an invention of script writers (with no aviation knowledge) looking for excitement or drama. Even at high altitudes, a bullet hole will cause a small leak, and a rapid decompression is unlikely. At worst, if the leak exceeds the capacity of the pressurization system, an emergency descent to 10,000 feet or below would be initiated, and the flight continued.

Answer 2

Depends where the bullet hole is in the airframe. Yes outflow valves are in the airframe but these are strengthened etc. If you rip a hole next to a seam at the bulkhead you may get a zipper effect like what happened to Aloha Flight 243 . That tear that ripped off a big part of the top of the plane started as a fatigue hole about 1/4 inch. And you didn't mention how big the bullet hole is either. If this is a howitzer (105mm) it couldn't cause quite a problem. But generally a small caliber bullet hole will only create an obnoxious whining noise.

I think you may also be a little off in your 8,000 figure. That is the cabin pressure differential (about 7.5 psi at 35,000). It feels to the passengers like they are at 8,000 feet. Not that the plane is flying at the altitude.

Oh and finally the Mythbusters were wrong. Aloha airlines 243 proved that people do get sucked out. By passengers account the flight attended got sucked into the small hole and the fluid-hammer effect exploded the fuselage as she "stopped up" the hole. They never found her body. The other attendants were not sucked out as they were further from the hole (and you know a vacuum isn't directional).

Answer 3

Contrary to the above answers, any plane that has a pressurization system will most likely be pressurized while flying at 8,000 ft, unless there is a problem with the system. Thus the "cabin altitude" will likely be around sea level. If you were to fly a high performance jet or turbo-prop unpressurized aircraft up to 8,000 ft (unless you climbed very slowly), the pain in your ears would unbearable. To answer your bullet question: planes have plenty of "holes" in them where pressurized air normally escapes. The main source of pressurized air leaving the cabin is through "outflow valves" thus controlling cabin altitude. A tiny bullet hole will not have any affect on cabin pressure, as Hollywood would want you to believe. A bullet causing a gaping hole in the side of an aircraft, is another matter. Check out that episode of Mythbusters, it was way cool!

Answer 4

You would need to be twice as high, and the only thing that would happen would be that air in the cabin would slowly leak out, until equilibrium is established.

(Think about a glove with a tiny hole in it.)

Did it on Mythbusters. (Explsoive Decompression)

Answer 5

At 8000 ft pressurization is not needed however the differential at that altitude would be minimal. Nothing except it would have a high leak rate...duh. I am VERY curious as to why you want to know!

Answer 6

Really nothing will happen because airplanes will not usually be pressurized at 8000 feet. The typical cabin altitude for an airplane to be at is about 8000 feet. So there would be no point in pressurizing because cabin altitude would be the same as atmospheric pressure. If the cabin was at a lower altitude, then there would just be a gradual loss of cabin pressure, but nothing to destroy the airplane or its occupants

Answer 7

Nothing. Pressurization is only needed above 12,000 feet. It may be a bit drafty, but no ill affects will come to the bird.

Answer 8

Nothing but noise, unless the bullet hits something important on the way out.

Answer 9

There will be rapid decompression, objects will be sucked out of the hole with force, creating an ever larger hole, the airplane will most likely spin out of control and crash. That's the worst case scenario. However, if the pilot loses height quickly enough, and brings the air crafts pressure equal to the outside atmosphere, he may keep the plane under control and land safely.

Sorry, I saw 8,000 feet, but I was thinking 60,000. Scrap the above scenario.

Answer 10

8,000 feet is nothing. I have been higher than that with the doors open and the cargo ramp down.