Cryptic Cay

You’re on a small unauthorized expeditionary trip, with only an hour of flight to go, the pilot suffers a heart attack. His strewing about causes him to drastically change the pitch of the propeller and immediately reverse the thrust on your cruising plane. Both propellers snap off. You start to plunge to the blue surface of the earth below. You barely manage to strap on your parachute, blindly jump out the nearest door and yank on the ripcord. You see a patch of green land in the middle of a blue sea. You use the steering lines and aim for the only part of the island that seems to have some sort of developed structure on it. As you come streaming down, you pass over a primitive tribe that greets you with a barrage of arrows. They all fall well short and miss but you now know that you’re an unwelcome visitor to their island. You continue towards the structure only to find out it is a fortified military building with a radio antenna sticking out of it. Your only hope for survival is to get inside and radio for help, but can you do it before the tribes hunting party finds you? You have one hour to find out.