As of today she is on a level 2, but when we purchase I will be ordering the Inogen 5 so as she progress it will still be useable . Where do you get the info on the requirements at 30,000 ft ? I tried to print the form from delta but it’s in a pdf form I guess I’m going to have to as my grand children how to do it. When on the island do you rent a portable unit or a stationary unit when I booked this trip it’s for 25 days, if we do make the trip who knows how long we stay. After you submit the doctors form with her requirements do you have to resubmit it went you return.