One of the most unforgettable pictures in the history of small boat passage-making is Gipsy Moth IV rounding Cape Horn. An almost wingless ‘moth’, the ketch runs the last of her easting down under spitfire jib alone. To port and starboard are horrifying white craters: the death of two giant waves, one and a half times the length of the 53ft hull.

‘Wild horses could not drag me down to Cape Horn and that sinister Southern Ocean again in a small boat,’ said Chichester. There is something nightmarish about deep breaking seas and screaming winds; I had a feeling of helplessness before the power of the waves came rolling down on top of me.’

When he set out from Plymouth on 23 August, 1966, Chichester’s project was ‘simple enough’ — to race against the average time of the Australian wool clippers — 123 days. Chichester hoped to beat the best time of 100 days, but after a knockdown 2,900 miles from Sydney, which damaged his windvane, he jury-rigged his self-steering and limped through Sydney Heads after 14,000 miles and 107 days — still a remarkable passage.

When he rounded Cape Horn on the leg home, teams from the BBC and The Sunday Times flew over in a small plane to capture the famous picture. Chichester, 65, arrived in Plymouth on 28 May, 1967, having covered 29,630 miles in a sailing time of 226 days, averaging 130 miles a day on the 15,517-mile leg home from Sydney.