Airborne Wireless Network (ABWN)

[Pilot Dave]

Because they need to see, among other things whether or not there is any interference with the avionics,radar, HF,VHF radio frequencies etc. It's not about simply raising a signal a few hundred feet above the ground just to let the signal fly, it's about getting up into controlled airspace where trillions of electronic signals are all around being generated and bounced. Then the biggest part of testing to get it up to high altitude where signals can get sent way over the horizon. A piper cub as you call them and most light aircraft fly well below 10,000'If I remember right at ground level you can't see past about 7 miles due to the curvature of the earth. These signals are line of sight; they don't curve around the earth and follow the curvature so when you can get up to 41,000' the added distance to the signal can be in the thousands of miles more, and that is the main objective is to get these signals sent farther than can be done on or near the earth's surface. Then imagine how much farther yet two aircraft can send and repeat a signal if they were both at high altitude and a thousand miles away from one another. That signal could travel maybe a quarter way around the earth. Really it's just simple high school physics