It's a Farrier Trailertri 720. Sort of the fore runner of the F-24. It was built in a shop in Canada in 1985. Unfortunately ,I haven't come up with an affordable dry storage program and the rain is causing enough problems to keep me hustling to stay ahead of more work. I sailed it last year for a couple of weeks, which now makes the work worthwhile. That whole missing side started with the pic below.That hole was about an inch by an inch. I think it was a repair with sub standard marine ply, and the ply delaminated. Goes to show ,if you go looking for trouble you'll find it.
Todd