When I arrived at the parking lot at the Jordan River Parkway this morning, I saw two guys launching a RC dirigible. The airship was about 20 feet long and probably 3-4 feet in diameter. It was propelled by an electric motor in the tail of the airship. There was no gondola on the bottom of the body. It flew for about 5 minutes and then did a nose dive into the ground behind some trees. I didn't see the impact, but the crash made a lot of noise.
The crash didn't seem to damage the airship, because the two guys retrieved the ship, put more helium into it, and then launched it again. It flew for about 20 minutes. I was curious how they were going to land it. For the landing, the airship did a slow dive towards the ground. Just before the airship hit the ground, the assistant pilot grabbed the nose and stopped the descent of the ship. The other guy took the tail, and they carried the ship to their truck.
A few weeks ago, I saw a guy flying a RC jet F15 or something. The plane had a real jet engine, and it went pretty fast.