Years ago when JG11 had many more pilots every week, as all of our squads did.
We were in FW-190s but part of the attackers. We came across B-17's with escort out of position.
It did not end well for the B-17's that night. That started the conversation about attackers not engaging the enemy attackers.
I am pretty sure, did not go back and read the discussion, that everyone was on board with letting attackers go.
We have been on the receiving end of this in JU-88s as well.
About a year later we were once again in FW-190s and flew right by a big formation of B-24's...... Oh the TEMPTATION was there
But STAMPF kept us on mission.
Last Friday when our attackers crossed paths, we heard the call of Hurris attacking so a few of us went in to chase them off. On the way back we saw the B-25's
We just flew by as a recon for speed and altitude and direction. I did not fire a shot.... from the guns but got a good recon photo
It may not be a rule, but I am pretty sure that most, if not ALL of us know if you are on the attack mission and you see the enemy attack mission, you just keep on flying... after you call out alt speed and direction