YYtz you seem oblivious to the fact that this IS the leniency a genial posek came up with. A huge leniency that not everyone accepts, and which incidentally I believe to be valid only for pressurized aircrafts. On top of that you and other posters are trying to paint us as fools via reductio ad absurdum. Tumah is definitely a problem for cohanim at “thousands of feets” or a few hundred meters. It is not a problem at jets’ cruise altitude, on spacecrafts, or with the moon.
True, I take everything you write with many grains of salt. I don’t mind if you eat macrobiotic, this is a personal preference. I have issues about people advising (a very young person) before thinking twice. Some speak very well about that place and some others did not enjoy it (to use an euphemism); it is a controversial place for a girl or woman to be, and one should at least recommend to hear many opinions.