Spy Balloon Freakout

You are a Spy Balloon floating in enemy airspace. A fighter jet has been scrambled to intercept and shoot you down! Worse, surface-to-air missiles are aiming right at you!! Fly! Fly for as long as possible, and see how long you can stay aloft!! "Saddle up, airman! We've got a bogey at Angels 40!" -Someone, Somewhere