Hak you have to ask a bomber pilot if he wants/needs a gunner. If he says yes then in the radio bar you type .join <handle> where <handle> = the pilots handle.
IE> .join Rocket
NOTE:Once the mission is over and you are in the tower you must type .unjoin <handle> to get out of the plane. otherwise you are stuck till on the ground again. Isn't so bad if he takes another bomber but really sux if he flies a fighter.
Also after your 2 free weeks you will not be billed you must sign up for a paying account by submitting your credit card # or sending HTC a check/money order. H2H is always free
S!
Rocket