Revealing mistake: Towards the end of the movie when Burnett is by the plane's ejection seat, you see a puddle of water by him with snow flakes floating on top of the water. Snow flakes dissolve in water as soon as they hit. They use a corn starch type mixture to make fake snow, and that is what you are seeing in this scene.
Revealing mistake: When Owen Wilson is trying to restart the beacon in his ejection seat, his right hand is ungloved. Yet in the scene before, he took off his left glove. It is my belief the negative is reversed, as you can catch a quick view of a Duracell battery with the letters mirrored.