Invincible or respawn?

[wld427 1705]

i have a base in my mission and i have some harriers that fly by , orbit, and fly away in order to chase away SLA choppers. I wanted to use this script to protect my harriers. Unfortunately they are still destroyed by the SLA.

Anybody have any ideas how to prevent this?

init="this addeventhandler [""dammaged"",{(_this select 0) setdamage 0}]; this addeventhandler [""hit"",{(_this select 0) setdamage 0}];{_x addEventHandler[""dammaged"",{(_this select 0) setdamage 0}];_x addEventHandler[""hit"",{(_this select 0) setdamage 0}];} forEach (crew this)";