helipath_loop_crash.map

Here is my helicopter trio.

When adding this to your map, open the helipath_loop_crash.map in radiant and then press I to copy selection

then open your map back up and place it in that way.

If you place this as an actual prefab you will have to enter the prefab to move things around as you will need.

If you do this the old school way and click on everything to copy it, THEN DON'T forget the heli_leave sitting way off to the side.

Here is the link that leads you to the tutorial:

http://dev.xtremeidiots.com/topic/129-adding-a-helicopter/