William Newton Darby – always known as Tony – who has died aged 91, was one of three children and a direct descendant of the Quaker Abraham Darby, innovative iron-founder and builder of the world's first cast iron bridge.

He was born in Salford, but the family moved to Bradford when his father became involved in wool textiles. Tony went to Bradford's Grange Grammar School where he obtained his Higher School Certificate. With this he could have gone to university, which was his ambition, but his father insisted he get a job instead, and reluctantly he joined the Commercial Union as an insurance clerk. At the outbreak of war, torn between the pacifist Quaker influence of his upbringing and the feeling that he could not stand by while the Nazis threatened England, he joined the Royal Medical Corps.

At a church dance soon afterwards he met Norah Fisher, and while waiting to be told where he would be sent for training, he married her. A month later, in October, 1939, his unit was attached to the Gordon Highlanders in Scotland.

His training completed, he was sent to join the British forces in Tobruk, but on the way, his ship was diverted to Singapore which was being threatened by the Japanese. Ten days after he arrived, the Japanese overwhelmed the British stronghold, and the 23-year old spent the rest of the war doing forced labour as a Japanese PoW. He worked on the infamous Burma railway, among other things, and was always expected to use his medical training to treat Japanese soldiers as well as his fellow prisoners.

For three years Norah did not know if he were alive or dead.

His experiences at the hands of the Japanese affected him so deeply that for many years after the war he was unable to speak of them. One form of therapy he adopted was walking, but Tony Darby did nothing in a casual way and ended up leading walks for the Ramblers' Association, Bradford Senior Wayfarers and the Holiday Fellowship.

He returned to England in late 1945 and resumed the job he hated at the Commercial Union. By now he had decided to become a teacher, and was offered a place to do his Certificate of Education at Leeds University, completing a history degree first.

The only teaching job available after he qualified was at Odsal House deaf school – in the 1970s it was shut down, reopening as Thorn Park School – where he remained until his retirement, as Deputy Head, when he was 65.

When he first went to Odsal House, he was the only young man on the staff, and he soon introduced football and cricket – and more importantly for what subsequently happened – swimming, a sport in which he realised that deaf participants have no disadvantage.

Tony trained the squad of three girls who won medals at the World Deaf Championships in Belgrade in 1969, following which, Bradford Schools were quick to recruit him.

He was to become a familiar figure in his trilby and tweed coat – the trilby so much a part of his identity that it accompanied him on his coffin. He was also one of the coaches who started off former Olympic champion swimmer Adrian Moorhouse's career.

Extraordinarily, he had an intense dislike of being in the water himself.

He became treasurer and a coach at Bradford and District Amateur Swimming Association, and was still coaching at 85. In 1981 he was honoured with the first City of Bradford Service to Sport Award.

Two years ago he moved to live with family in Aberdeenshire, Norah dying in 2006. He is survived by their daughters Angela, Hilary and Sheila, two granddaughters and his sisters Betty and Grace.