Air Lock

Air Lock

Airlocks serve as the entrance and exits to spaceships, whether it is docking with another ship or for extravehicular activity (EVA), without compromising the atmosphere of a spaceship. They consist of a hyperbaric chamber with a pair of airtight doors, one allowing access to the ship's interior and the other to the vacuum of space. The chamber can be pressurized and depressurized in a controlled fashion

Throwing someone out a spaceship or space station's airlock without a suit, or as some universes call it, "spacing," or simply "airlocking," is a common method of killing / executing.. Union Fleet uses this as accepted method of execution. By all accounts, getting exposed to the hard vacuum of space is not a pleasant way to die.