I just tried but it crash at game start.
The .XML i edited is here ;
C:\Program Files (x86)\Steam\SteamApps\common\take on helicopters\AddOns\air_us_h\hsim\air_us_h\helicopt ers_light
Then to repack I done a right click on the Air_us_h folder, and create pbo. Replace the new by the old etc... But it don't seems to work