- Only one unit is visible (a Breguet 693 bomber in my game)
- If you attack the hex with a fighter, it will target the B.693
- But the French fighter in the same hex will support the B.693. This is how you can tell that there are multiple air units in that hex
- If you kill the bomber, both the bomber and the fighter die
- It's possible there are more than two aircraft in that hex, since the whole stack dies when the bomber dies
I can provide screenshots to illustrate if it would be helpful.
Edit:
My last bullet isn't always true. Another time they spawned and I used AA first to weaken the stack and then used fighters to kill the bomber, and the fighter (a Morane-Saulnier 406) remained. But it was still buggy: when I moused over the enemy fighter using an unspent German fighter, I didn't get any combat predictions. I was still able to force the combat, but it was as if I had the Arrogant general trait for that fight.

