I have both a Z1 and Z2 (from cpap.com). I think it’s the smallest machine out there. I haven't used it in air yet but I did order a battery pack which is supposed to last a full night. A lot of planes have outlets these days but that might be an option for you. I travel every week for work and love the Z1 and Z2 personally. It fits in the backpack and I leave the hose, mask and power supply in my bag. Unlike the bulky machines where everyone knows you are carrying a CPAP this one is discrete.

I have a few flights to Europe coming up. I typically don’t sleep on planes and I am thinking about it (I hope to be in business or first where it’s semi privacy) but I’m a little concerned the noise may be too much. Planes out loud so I doubt it I just wouldn’t want to upset another passenger.