RNSA = Royal Naval Sailing Association. One of the first ‘offshore one-designs’ and the brainchild of Capt. J.H. Illingworth. His own ‘Minx of Malham’, the first of this design, proved herself in her first season by taking the RORC small-class championships of 1949.

Boats of this design were also built in Hong Kong and Australia.

Information courtesy of Sailboatdata.com