What locking device is usually used to keep the inside section from falling... a clamp or pin of some kind? I've never had a crank up here.
Ouch! I've heard stories but none with anyone near to me. Lost limbs, in some cases. Get one of those big jobs cranked way up, it's like a train on rails coming down. He probably doesn't feel like it Joe, but he's extremely lucky to have gotten away with his toes, fingers, hands, etc.
Tom, the 55' Triasto I had used only the tooth lock on the hand winch. Still have my old 45' EZ-Way 2-section up behind my folks' place, it actually has a spring-loaded hinge plate near the top of the lower section that snaps into place as each horizontal member of the zig-zag goes by. To lower the tower, you have to pull down on a rope attached to it to hold it out of the way. Kinda tricky holding that with one arm and trying to crank the winch with the other. Hooking the rope in place would make it easier.
I learned early from my old BC engineer buddy KC1BT to trust nothing and no one when it comes to safety. He always kept a large steel pipe or hardwood chunk of 2x4 handy to slide through the tower. Depending where you slide it through, it will hold the tower in place or let it slip as much at a foot or so if the cable snaps. If the tower is up, you have to climb with the pipe and slide it through when you get to the bottom of the upper section.
Having had a steel cable snap on me while lowering a regular tower, I know it happens all too easily. in this case, a fellow helping out over-tightened the clamp on the end wrap of the cable, causing it to cut through enough strands that it let go was we reached the point of no return. Brand new cable, too.