How do you unlock a jet in decepticons ds?

How do you unlock a jet in decepticons ds?
you cant, after you beat the game you have to play as starscream. I think you might be able to find something that is a jet at hoover dam but other wise i have no clue. you cant, after you beat the game you have to play as starscream, other wise i think you find it at hoover dam inside the sector 7 base. if you find how post your idea.