Happens all the time get used to it. I'm Dancing with a 190 at 400 on his six and some little squeaker from Texas comes in my line of fire and gets the kill as I'm forced to hold my fire to avoid a kill shot. After I had spent the time getting position.
I will fly behind others as back up but will not engage thier prey unless they get into trouble.
We all see the simpletons that insist on firing on a falling wreck getting the kill. The only one that should be fired on is those Jap Candles as they flame for 5 minutes.
Some of our biggest enemies are on our own side.