I have recently been looking into the history of pressurization and was intrigued to learn that the effects of high altitde (quite apart from oxygen flow) can be quite severe.
So these are probably stupid question to those closely involved with flying, but here they are anyway:
- Are military transport planes pressurized (since they can transport paratroopers, litter patients etc.), and can they be depressurized in flight for e.g. high-altitude-low-opening jumps?
- Are (civilian) cargo aircraft and the cargo holds of passenger airplanes pressurized or not?
- Are helicopters pressurized at all?