When the CSLA UH-60 is destroyed in flight, the wreck can stop falling, and be replaced by the custom wreck object, above the actual ground surface. This results in a floating wreck object. This seems to happen primarily in multiplayer with more than one person, but I don't have a 100% reliable repro.
Place a CSLA UH-60 in midair, so it spawns flying. Give it a variable name like v_helo.
Play the mission from somewhere you can see the helo.
From the debug console, execute v_helo setDamage 1; and watch it fall.
Observe that _sometimes_, the custom wreck object appears floating a couple of metres above the ground.
If it doesn't occur in local testing, try it on a dedicated server with multiple players observing.
I suspect this is because of inaccurate bounding boxes for some of the models involved, but can't prove it.