I want this boat lift

skennelly

https://www.youtube.com/watch?v=l1TNqBmmacE

skennelly

https://www.youtube.com/watch?v=uqe8Od_olFI&feature=youtu.be

Handymans342

I want a sling type

randy56

That's fast

Ian

Look at these emergency units they put on ships as shown at  http://www.canalmuseum.com/canalphotos/equipment-011.html. These fly off a lot quicker at a higher angle and in freefall.