Kerbal Space Program

Currently, Kerbals on EVA will not have helmets on Kerbin (not sure if same applies to Laythe or other bodies with suitable atmosphere).

If you put a Kerbal on a command chair attached to a spacecraft and make them go to orbit, you'll end up with a helmetless but very alive kerbal on EVA in space. Unless, of course, kerbals don't exactly need spacesuits for life support purposes... maybe they're like batman.

Solution would be to implement a life support system that makes the kerbal go unconscious or even die if they exceed certain altitude (or speed) with no helmet on, and make a toggle menu for helmet on/off in atmosphere.

Alternatively, just make Kerbals use helmets when they mount a Command Seat. It would probably be easier fix, even if the helmet appears from "thin air" when the kerbal sits down into the chair.