It works that way in the movies,

but only makes a bullet sized hole in real life and only then if fired at an ideal angle and only if it makes it as far as the outer skin. And only then would it make a leak and only a number of such holes equal to a square foot or so, could outrun the N2 compressor sections enough to make a detectable difference in the cabin air pressure or engine thrust.

 

Lynn E. Hanover

 

 

 

Is it true that a single stray bullet in an airliner at flight lever could/would lead to a catastrophic decompression.  Granted, you'd get the terrorist, but is it worth sacrificing everyone on board?