Water skiing is a sport where an individual is typically pulled behind a boat or a cable ski installation on a body of water, skimming the surface.

Ken Warby (born 9 May 1939) is an Australian motorboat racer, who currently holds the Water speed record of 317.60 miles per hour (511.13 kilometres per hour). This was set in Blowering Dam, part of the Snowy Mountains hydro-electric scheme, near Tumut, New South Wales, roughly 250 miles (400 km) south-south west of Sydney, on 8 October 1978.

As a child, Warby's hero was Donald Campbell, who died attempting to break the record in 1967.

Warby designed the hull of his record-breaking boat, Spirit of Australia, himself and built it in his backyard. He started the project as a Makita salesman who happened to team up with two Leading Aircraft Men at RAAF Base Richmond in the early 1970s. Crandall and Cox were instrumental in installing and engineering the Westinghouse engine that was not in working order when first obtained. The Spirit was covered with a canvas tarpaulin when it rained and was made of wood and fibreglass. Warby was able to obtain the jet engine himself as military surplus; obtained from an auction for only $69.