TJH wrote:
OK, perhaps this might sound strange, but I'd like to drop a car from a
crane.

I'm thinking about doing a project for a high school senior class to
show the violence of an auto crash (educational for prom week) at
roughly 30-45mph. In order to do this, I'd hoist an auto by a crane up
say 40 - 50 feet, and then drop it to the ground. But, to do this, I
need some type of quick release mechanism, because the crane owner
isn't going to risk damaging his equipment by free-falling the cable.

I've thought about using heavy duty strap webbing with a quick release
buckles, but I'm not sure if they would support the weight. The release
has another problem - how do I do it from the ground? Ideally, I would
have some sort of remote controlled release, but wireless? Wired?
Mechanical? Cheap and easy is the challenge as well.

If any have any suggestions, I'd love to hear them.

A marine snap shackle might work:

http://shop.torresen.com/ships_store/?p=categorydetails1&defaultbrand=Ships+Store&defau ltstore=Ships+Store&sectionid=5111