Reward: Highest Airport
Difficulty: Easy
Estimated Time: Varies
To earn this reward, you have to land at San Rafael (SPRF), located in Peru. Keep in mind when landing here that the airport elevation is 14,400 ft. Make sure that the aircraft you choose to fly is able to operate above 15,000 ft, because you will need to climb over a few hills to get to the airport. If you can't get any power out of your engine, don't forget to lean the gas mixture (pull the engine mixture control towards you until your EGT gauge peaks, then push it in just a touch) or enable the engine auto-mixture (in the aircraft realism settings panel).
Or you can takeoff with a helicopter, hover 100 feet above the runway, then set it back down.