Strange problem with OnTrigger

Okay so i have no clue whats wrong here. Everything was working fine and im not sure what i could've clicked to break this. Problem is when normally playing, this collision occurs: http://pokit.org/get/?c1dc7e5abb7f98ce5a5e6a2c3f62dc46.jpg

you can see 2 objects overlapping, but their colliders are set the right way, it even works when i switch ANY option in the player plane's rigidbody (enable/disable is kinematic for example) but only for that one frame where that change occured, OnTriggerEnter gets called and the plane is destroyed, but no matter if another plane hits the player it wont call OnTriggerEnter anymore, unless i change an option in the rigidbody again.

What could cause this? Everything is set fine, the colliders are box colliders on both objects with huge Y scale to avoid one flying slightly above the other, and the textured plane has a rigidbody.