Muriel Petch: WAAF sergeant and ‘Ops Room’ plotter at RAF Hornchurch who helped win the Battle of Britain

Muriel Petch lived to be 103 and was one of the last handful of “Ops Room” plotters who helped fight the Battle of Britain in 1940. The scene is familiar from any number of war films, in which uniformed and attractive young women extend long poles to push arrows about a huge table while firm-jawed chaps with stripes on their sleeves look on, brows furrowed.

Petch, who ranked as a sergeant in the Women’s Auxiliary Air Force (WAAF), worked under the gimlet gaze of Squadron Leader, later Wing Commander, Ronald “Ronnie” Adams at RAF Hornchurch in Essex throughout that summer of aerial dogfights while tension crackled high that a German invasion was imminent and Britain stood alone.

Petch would display the colour-coded symbols showing Hitler’s Luftwaffe coming across the North Sea to attack, in swarms of 300 aircraft or more, alternately watching the clock on the wall, its face also colour-coded, and listening to the data given over her headphones. It was gathered by Observer Corps members gazing through binoculars from rooftops, and from the cumbersome early radar system called “Chain Home.”

Petch and her team, working in shifts eight hours on and eight hours off, would place each arrow for five minutes, then get a new reference, and place it again. Early in the war the arrows were made of bone; later they were metal, and the sticks had magnets. RAF Hornchurch was on the front line, under southern England’s “bomb alley”, the route the enemy took to reach London. It was bombed at least 20 times during the Battle of Britain, and several staff were killed, including airmen whose Spitfires were destroyed on the ground.

A heavy raid on 3 September put Hornchurch’s ops room out of action altogether, and the map, the arc-lights, and the shift-working team were all rehoused in a small unoccupied grocer’s shop a few miles farther east at Grays, where Adams said, “we were sitting very much on each others’ laps,” so cramped were the emergency quarters.

Three days later, on 6 September, came the strike that blew up the oil tanks on Canvey Island a short distance down the Thames estuary, which Petch remembered vividly: “We could hear the sound of the battle approaching... about 4.00 pm the communication went dead... we all went outside and could barely see due to the smoke from the burning oil. We could see parachutes coming down and many aircraft in the sky.”

Britain was running out of replacement planes, and it was doubtless at touch-and-go moments such as this that the strain drove a colleague to write anonymous caricatures in verse that Petch kept for the rest of her life. The one about her declares: “There once was a certain ops B / Whose surname commenced with a P / All others in ops / she considered were flops / Like a trumpet she cried: “Look at me!” It was by no means the most waspish.

Nine days later, on 15 September, however, the Luftwaffe onslaught faltered, and the Battle of Britain was considered won. The Hornchurch team removed back to base from the grocery shop, which during their stay had itself been bombed.

Petch’s strength of character was next tested when, in December 1942, the RAF was planning a low-flying daylight raid on the Dutch Philips electrical company’s Eindhoven factory, which had been taken over by the Nazis and was producing radio valves for the Third Reich. RAF chiefs asked Petch, who had Dutch acquaintance, on which side of the town’s railway line it lay.

She knew the lay-out because friends she had met on a pre-war sailing holiday were employed there. She must have thought of familiar faces, already probably including that of the man she would eventually marry, an engineer at the factory called Cornelis Vlaanderen. But she did not hesitate. The directions she gave were spot-on, and the raid destroyed the huge modern complex for a toll of 148 civilian lives and 12 British aircraft lost. Her friends survived.

It was Petch’s independent and adventurous streak that had first impelled her to volunteer for the WAAF. On leaving the local school at Twywell, Northamptonshire, where her family lived, she went at 18 to act as “companion” to an aunt in London, then took a job with the department store Bourne and Hollingsworth, living in its Gower Street hostel and relishing single life in the capital. She left at the start of the war when refused time off to visit her soldier brother home on leave, and joined the WAAF.

After the war Petch worked for some years as a laboratory assistant at the company that designed the boots Edmund Hillary and Tenzing Norgay wore for the first ascent of Mount Everest in 1953. This was Satra, the British Boot, Shoe and Allied Trades Research Association at Kettering, Northamptonshire. In 1953 she married Vlaanderen in England and the couple went to live in Hilversum in the Netherlands, where Vlaanderen now worked, still with Philips. He was invariably known as “Kees”. His wife became fluent in Dutch.

There were no children, and after his death in 1975 Petch returned to live in Northamptonshire, visiting Dutch friends in the Netherlands frequently, her last trip thither being at the age of 102 in 2012.

Muriel Ellis Petch was born in Gillingham, Kent, the youngest of six children of a Royal Navy gunner based at Chatham who had served in the Far East in 1900 when the Chinese Boxer Rebellion threatened British lives. On his retirement the family moved to Northamptonshire. Her eldest sister Ethel set up hospitals in North Africa and ltaly in 1943 and 1944, and her brother Cecil fought in Egypt with Montgomery. She outlived all her siblings.

ANNE KELENY

Muriel Ellis Petch, WAAF sergeant: born Gillingham, Kent 1 July 1910; married 1953 Cornelis Vlaanderen; died Woodford, Northamptonshire 29 March 2014.