He had, however, fallen in love with Barbara Murray and, with only wives allowed to accompany departing officers, they quickly married and flew to Sumatra.

The Japanese had destroyed much of the local Sumatra shipping, and Gavin and Barbara at first found themselves marooned. But as an engineer and a keen sailor, who had participated in the Fastnet race, he was able to rig up a tug, and together they sailed to Ceylon before embarking by train for northern India.

It was during a riot on the train that Gavin suffered the heart attack that was to break his health, and leave him considerably weaker for the rest of his life. After recuperating in Kashmir, he re turned to Europe to work on sabotage equipment for SOE.

In 1944, on the verge of being parachuted into northern Italy from his post in Cairo, he was transferred to General Eisenhower's allied headquarters at Versailles.

Gavin went on to hold senior posts with the Royal Engineers, and became a general staff officer at the British joint services mission in Washington, between 1948 and 1951. He then commanded 36 Engineer Regiment at Ripon, was a general staff officer at Camberley, and commanded 11 Engineer Group at Osnabruck.

He ended his military career in 1967 as assistant chief of staff (intelligence) at SHAPE, the Supreme Headquarters, Allied Powers, Europe.

He then spent 10 years as technical director of the British Standards Institution, working on the introduction of metrication, before retiring to Milland, near Liphook, Hampshire.

After his wife died in 1994, he spent the remaining years with his daughter in Dorset.  They would have 53 years together, and two daughters and a son.

• Major-General James Merricks Lewis Gavin, mountaineer and soldier, born July 28 1911; died August 21 2000

From the Times Obituary and my conversation with him and his letters from his daughter Fay.

His personal notes and diary are deposited in the Lidddel-Hart Library in London.