If you mean mark target you need press "Q" and you will be able to spot an enemy, if you want shoot another helicopter from your drivers position you are able to change missiles from machine gun by pressing "F"
When you say set-target do you mean spot? If you're playing on the PC you use the Q key to spot whild flying to mark a target.
HE MEANS ON PC
The last post in this thread was from 2 years ago, there's not reason to necro a thread to give a salty response. I'm closing this thread.
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