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Better Helicopter Startup Sound

I always couldn't stand the startup sound for the helicopter in the Parish finale as there was no real engine sound, or that sound of the different parts of the rotor system starting and it just started too quickly. This version is the one I have been using for about two or three years. The startup sound actually takes 39 seconds now with a looped section of 30 seconds as well. It sounds much better running to the rescue now. I hope you enjoy!

As with the jets addon

Extract to the required folder (steam/steamapps/common/left4dead2/left4dead2/sound/animation) and rebuild the audiocache as these sounds are longer than the unrealistic originals.

EDIT Use Gcfscape to extract the sound files to the sound/animation folder in your left4dead2 folder use ~ to open the console and type snd_rebuildaudiocache this will stop the sounds from cutting off as they are LONGER

First open with GCfscape, I also open the Left 4 Dead 2 sound folder and look for animations, extract the sound from the folder and make sure to overwrite the file. Check to make sure the file is not cutting off, by opening it with whatever sound player you use. Go into the game and type snd_rebuildaudiocache it will seem like the game has locked up, but it is registering all of the audio files. When it has finished type exit to close the game then you can unsubscribe from the addon if you want and re-enter the game.