[Nick Beale]

I'm sure there is a previous thread about this somewhere. My understanding is ...

Feindflug = a flight against the enemy, either crossing the line (or the coast?) or to intercept hostile air forces over your own territory.

Heimatflug = a flight within your own lines that is not against hostile aircraft. This could be a test of transfer flight or even one against a ground target (I have seen a logbook where anti-partisan missions in Russia are not classed as a Feindflug).

"Frontflug" also occurs sometimes. I ahve seen it with reconnaissance aircraft and it seems to be flight to the front lines but not across them.

Other people will no doubt add to this.