If the old-fashioned designation aviatrix were still current, it would undoubtedly be the terminology with which to describe Diana Barnato Walker. A dashing, petite woman, she had begun flying in the era of the pioneers Amy Johnson and Amelia Earhart. She served during the Second World War as a ferry pilot in the Air Transport Auxiliary, in which women played a vital role in delivering new aircraft from factories to RAF and Fleet Air Arm squadrons, coming to the aid of the available reserve of hard-pressed men pilots. She continued flying well into the jet age, and in 1963 became the first woman member of the “Ten-Ton Club” when she piloted an English Electric Lightning jet trainer at a speed considerably exceeding 1,000mph.

Glamour and Diana Barnato Walker were indivisible. Her family background was wealthy and colourful, verging on the buccaneering. Her grandfather, Barney Barnato, had been a comedian in London before turning diamond mine speculator in South Africa, where he built up a dominant position in the Kimberley mine until forced by Cecil Rhodes into a merger with De Beers. Having subsequently suffered heavy losses, he later disappeared overboard from a ship sailing from Cape Town. Diana’s father was the millionaire racing driver and chairman of Bentley, Woolf Barnato. Known as the “babe” among the Bentley Boys, he won three successive Le Mans 24-hour races with the company’s cars between 1928 and 1930.

Diana Barnato was born in London in 1918. Since her parents split up when she was 4, she spent her childhood between her mother’s Hampstead home and her father’s in Lingfield, Surrey. As a child she enjoyed riding and hunting, but her father’s love of speed predominated. Flying became her passion, and she took lessons at Brooklands, going solo after six hours, at the age of 18.

When war came in 1939 she volunteered for the Red Cross and in 1940 was serving as a nurse in France before the evacuation of the British Expeditionary Force from Dunkirk. The establishment of the Air Transport Auxiliary offered new opportunities for the well-heeled young women who had learnt to fly in the 1930s. The ATA was at first staffed only by men — “Ancient Tattered Airmen”, as they were known, since most were civilian pilots too old for operations.

The pressing demand for more bombers and fighters as the war progressed accelerated the flow of aircraft from factories to the squadrons to the extent that at last the authorities bowed to the wisdom of calling on the reserve of women pilots that had been created by the enthusiasm for private flying in the interwar years. By the end of the war more than a tenth of the ATA’s 1,300 pilots were women.

Ferrying work might be routine, but it could be dangerous flying aircraft without radio and navigational aids in all weathers. Even the veteran Amy Johnson fell victim to its hazards, baling out when her aircraft ran out of fuel and losing her life in the freezing waters of the Thames Estuary.

Barnato volunteered as a ferry pilot in 1941, joining the ranks of the “Atagirls”, as the women ATA pilots were known — in a deliberately zippy contrast to their male counterparts. She was posted to No 15 Ferry Pool at Hamble in Hampshire, the first all-women’s ferry pool, commanded by Margot Gore. She soon graduated from singleengined light aircraft to Hurricanes and Spitfires, the latter always being her favourite aircraft. She delivered 260 Spitfires in all, without breaking one.

It was challenging work delivering different types of aircraft in all conditions. ATA pilots had to be versatile as perhaps no other class of pilot was. Having graduated to twin-engined bombers, Barnato ferried a Spitfire, a Grumman Avenger naval attack aircraft, a Wellington bomber and a Mustang to their respective destinations in a single day.

She was not only a fine pilot but also developed a technical know-how which enabled her to make a positive input into aircraft maintenance and development. Pilots had been continually complaining about the sluggish performance of the Avenger until Barnato divined that the installation of the superchargers was faulty, leading to a loss of power when needed. Gore and No 15 Ferry Pool received congratulations on the telephone from the Navy for this valuable discovery. On another occasion a Typhoon she was flying began to break up in the air, but by nursing it with the greatest care she was able to bring it safely in to land. By the end of the war she had flown 80 types of aircraft.

In May 1944 she married a fighter pilot, Wing Commander Derek Walker, after a lightning romance. When the war was over she prepared to settle into the life of an RAF officer’s wife, but it was not to be for long. In November 1945 he was killed when his aircraft crashed in low visibility.

With the ATA disbanded, she took her commercial flying licence and also devoted herself to the Women’s Junior Air Corps, instructing its young members in flying at weekends. While she was test-flying the WJAC’s Fairchild, “Grey Dove”, in July 1948, a few days before it was due to be officially christened by the Princess Marina, the aircraft burst into flames at 400ft above White Waltham. Rather than bale out and sacrifice the WJAC’s precious asset, she cut the fuel supply and brought the aircraft down again on a glide. With the fire contained, the burn damage was rectified in time for the ceremony to take place as planned. It amused her that the fire crew at White Waltham should have asked her why she was beginning to give them problems, when in the far more dangerous circumstances of wartime she had maintained a clean slate.

With the jet age establishing a new set of frontiers for aviators, one challenge that was bound to appeal to Barnato Walker was the sound barrier. By the time she obtained official permission to attempt it in 1963, she did so with some emphasis. The previous year she had been awarded women’s aviation’s highest honour, the Jean Bird Trophy. Now, at 45, she had first to take all the same decompression tests as any Fighter Command pilot.

Finally, on August 26, 1963, with Squadron Leader Ken Goodwin as her check pilot, she took a Lightning T4 trainer up to 30,000 feet, lit the afterburners and had the gratification of seeing the Mach meter climb through the sound barrier to 1.65 — 1,262 mph. At one stroke she had broken the sound barrier, established a world air speed record for women and become a member of the Ten-Ton (1,000mph) Club. It was the satisfying culmination to an aviation career in which she had flown 125 different types of aircraft.

Yet there were still fresh challenges to be surmounted. Shortly after her record-breaking flight, cancer was diagnosed and she had to undergo three operations. After being pronounced free of cancer she devoted an increased amount of time to the Girls Venture Corps Air Cadets (as the WJAC had become known), becoming its vice-chairman. She was also Commodore of the Air Transport Auxiliary Association, helping to keep together its members from 29 nations.

She published her memoir Spreading My Wings in 1994. She had been appointed MBE for her services to aviation in 1965.

Diana Barnato Walker did not marry again, but in 1947 had a son, Barney, from her long-term relationship with the married Whitney Straight, American aviator and racing driver who became a naturalised Briton and flew Spitfires in the RAF during the war.

Diana Barnato Walker, MBE, wartime Air Transport Auxiliary pilot, was born on January 15, 1918. She died on April 28, 2008, aged 90