1. go to the editor
2. place a random player unit (f.e. Autorifleman)
3. place a random empty vehicle (f.e. a Hummingbird)
4. place a respawn module (Modules->Multiplayer->Vehicle Respawn) and
choose following settings: Delay: 10 (10 second respawn delay)
Position: Starting Position(respawn position)
Wreck: Delete
5. connect the respawn module with the empty vehicle via sychronisation
(drag and drop)
6. preview the mission and shoot on the rotor blades (unload a full magazine).
Get in the chopper and its not moveable anymore but don't gets respawned.