Crossbow was an early 1970s proa (or asymmetrical catamaran) sailboat.
"She was 56ft long, built of cold moulded plywood, with a 60ft mast but only 22 inches wide." The smaller, outrigger hull was 30 ft removed from the central hull.
In 1972 it claimed the record for the world's fastest yacht at 26.3 knots.
Crossbow is still preserved and is owned by Sir Timothy James Alan Colman.