Is there a problem with a kohen flying in an airplane that may fly over a Jewish cemetery? If so, how can a kohen be sure that a flight does not go over a Jewish cemetery?
There are a number of issues:
- A flying object/tent is not considered a tent to separate.
- Something that is Mekabel Tum'ah cannot separate.
- A Kohen may not put himself in a circumstance of Tum'ah upon which a Nazir would have to shave and start over Nezirus.
The fact that the airplane MAY fly over Jewish Graves would probably be because it's like flying over a Beis Haperas (which most Achronim permit nowadays [see Taz 4 & Shach 2 on Yore Dai'ah Siman 369]).
There is also a Sofek Sfeka:
- Most Aronos have a Chlal Tefach
- Even if there is no Tefach in a specific Kever, maybe that body turned into Rekev
- Today we don't have Kohanim Meyuchasim (see Teshuvas Yaavetz 155).