The Invader 36 design was developed into the Frigate 36 in 1968, by shortening the long keel into a stub long keel, adding a centreboard and increasing the sail area.[1][3]
The Invader 36 is a recreational keelboat, built predominantly of fiberglass, with wood trim. It has a masthead sloop rig, a raked stem, a raised counter transom, a keel-mounted rudder controlled by a wheel and a fixed long keel. It displaces 10,575 lb (4,797 kg) and carries 3,800 lb (1,724 kg) of ballast.[1][3]