I have created simple project for that. Plane has set health (instance variable) to 3, and there is a group, which goes active when it is hit. However when plane health is below/equal 0, each plane is destroyed not just this particular one, i'm shooting at (another thing is that I need to hit it 4 times, instead of 3).
Again, as I'm new user I don't know if I'm doing everything fine :)
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