3 sources · updated 20 Oct 2026
Derek Kelsall was born on 15 May 1933 in north Wales. He began in surveying and the oil industry before turning to multihull design.
His first design, the trimaran Toria launched in 1966, was the world's first foam-sandwich trimaran. She won the first two-handed Round Britain Race and is credited with sparking French interest in multihull sailing. He went on to design Trifle, a 42-ft trimaran, and VSD 2, a 54-ft trimaran built in 1979 for Eugène Riguidel.
Kelsall later lived in New Zealand, where he died in Thames on 11 December 2022, aged 89.