How to make a spawn visible to only to friendlies?

[mongoose]

I think that I have finally got a working spawn for airbase approach and runway lights, but I only want them to activate for the friendlies, not the enemy. So far I have not worked out how to do that. Now the lights are in fact gun or flak 'vehicles', and in this case German vehicles, and in this case the spawn is 'German'. All is fine with a German 'player'; the lights show up; but with a British player, they also show up, which I don't want.
I want to make it so that if an 'intruder' aircraft shows up at a German Fligerhorst, the lights don't go on, but if a non player German aircraft also shows up, they still don't go on. Also if a German player ac shows up but a British intruder is around, they also wont light up!
Of course, one solution is not to include the spawn in a mission with an enemy aircraft in the vicinity; I am trying to avoid that option if possible. maybe reduce the probability to <10% or something?

[mongoose]

I guess that we are short of spawn experts!

[NachtPiloten]

..... we are getting into really thin air in here so sad to say.

[mongoose]

Well, I guess that all I could do if I make a missions with (player) Intruders, is to either not include the lights spawn and only the red flare, or change the probabilities of that appearing (with the die rolls). I suppose this would also be useful for non player intruders which might be after the Nachtjagd player ac.
The main thing is that I do have a working lights spawn!