看过MythBusters 里Adam专门实验在汽车落水后如何逃生

Episode 72: Underwater Car

If a car falls into the water and becomes submerged, you cannot open the door until the interior is flooded.

CONFIRMED

The pressure differential between outside and inside when the car is submerged is too great for a man to force the door, and the pressure must first be equalized, which means the interior must be flooded first. But it should be noted that Adam was forced to resort to emergency air in his first test. A second test later showed it to be possible to escape the car simply by opening the door, but only by remaining calm and not attempting to open the door until the interior is well and truly flooded, so as to conserve oxygen while holding your breath.