I found this in an old issue of Watercraft magazine, No15 1999. I seems like a very good idea for those who have poor boat ramps or muddy shores . It was designed for a Eun Mara yawl so it should be capable of launching most small boats.
If the pictures aren't clear enough I'll send anyone who is interested a scan of the original story and photos. I don't think a 13 year old magazine would be readily available .