Forget the ramp and trailer.

Back the boat trailer down to a beach. Get 3 or 4 people to lift the boat off the trailer and carry it to the beach. 4 people..... 1 each corner. 3 people...... one at rear beam and one each hull near the front beam.

If you have beach wheels it is made alot easier. One person can get the boat off. Place the beach wheels behind the trailer (G-cat is 5 mtrs long) place wheels about 3 mtrs behind. Slide boat off back of trailer by pulling and holding up at center of rear beam. Keep sliding and step over beach wheels and lower the transom onto the beach wheel cradels. Walk aroung an lift one bow and wheel the boat to the beach or grass rigging area.

Rig the boat with sails up... Get dressed then slide or wheel the boat down to the water and go sailing.