To remove the main rotor

1. Spawn a chopper
2. Take flight
3. Fly near another object so that the main rotor hits the object
4. Notice the rotors disappear completely

Try and achieve the same effect using scripts

1. Spawn chopper
2. Look at the chopper and open debug menu
3. Run cursorTarget setHit ["main_rotor_hit", 1]; locally
4. Notice that the rotor gets damaged but doesn't dissappear
5. Run cursorTarget animate ["main_rotor_hit", 1]; cursorTarget animate ["HitHRotor", 1];
6. Notice that nothing happens

Once the mainrotor is removed via collision (only works while the rotor is spooled up) you can repair the main rotor with setHit ["main_rotor_hit", 0] and it will return the mainrotor to the chopper.