Jud Herrig took down a 53' Aermotor tower standing on a farmstead in Minnesota. He did this by climbing up with his tool pouch and safety belt, and took it apart piece by piece. He simply dropped the 14' leg sections down and they stuck into the ground like darts. There wasn't a section bent at all. I can't recall if there was a gearbox on the top, or not. If so, he manhandled the gearbox and dropped it to the ground as well. I bought the tower from him at York, NE trade fair.
Dan Benjamin said he took down some tall towers like this by simply cutting the legs, and allowing them to topple over. This was in soft soil so it didn't really crumple.
Lance
