Did A 13 Year Old Girl Help Design The Spitfire’s Weapons System?

It would also have been much of a dream job for boys within her age but did a 13 year old girl helped design the weapons system of the iconic Supermarine Spitfire?

By: Ringo Bones

Now, 80 years after the start of the Battle of Britain on July 10, 1940, the RAF has finally recognized the role of an unseemly inventor and mathematical genius. In 1934, Hazel Hill, a teenage girl from north London, carried out the calculations that proved the new generation of fighter planes – i.e. Spitfires and Hurricanes – should carry eight fifty caliber machine guns, instead of just four. In a documentary researched by her granddaughter, Felicity Baker, a journalist, Hazel Hill’s contribution that allowed the Spitfire to dominate the Battle of Britain and denied the Nazi’s their British conquest finally got the recognition it deserve. Yet – until now – the compelling story of the schoolgirl who helped to win a war has been sadly untold. Hazel Hill’s only recognition was in a memoir written by her father’s superior officer in the UK Air Ministry.

Fortunately for Hazel Hill and her dad, the historic mathematical collaboration happened way before Number 10 declared that the Supermarine Spitfire’s design details were part of the UK’s Official Secrets Act or she could certainly have been denied access to it. In the summer of 1934, Hazel Hill, a 13 year old girl from north London, was approached by her father, Captain Fred Hill, a scientific officer in the UK Air Ministry who was trying to make the case for the new generation of fighter planes. Despite her youth, Captain Hill drew upon his daughter’s mathematical intellect and discussed plans with her as to how it could be possible to arm Spitfires with eight 50 caliber machine guns, as opposed to the four which had been originally suggested. Along with her father, she worked through the night on complex calculations that would shape the future of fighter planes like the Spitfire and the Hurricane. The work was done by lamplight over a kitchen table in north London. Night after night throughout the early months of 1934, Captain Fred Hill and his 13 year old daughter burned the midnight oil plotting graphs and laboring over complex algorithms.

When they got access to the new “calculating machines” of the time – which to our eyes today, resemble very rudimentary vacuum tube based computers – father and daughter worked long into the night analyzing the data that was previously obtained at their kitchen table. Their complicated calculations showed conclusively that each Spitfire needed to be capable of firing 1,000 rounds a minute – per gun. They also calculated the exact distance the Spitfire – whose top speed was about 360 mph – had to be from the enemy to hit them, just 755 feet.  The biggest thing was the huge increase in speed of the new fighters, which was way beyond anything people had experienced before – says mathematician Niall MacKay, the current head of the Department of Mathematics at the University of New York.

  It was tiring, unrewarding work but they both sensed how vital it would prove to be. And their instincts would before long be ratified by history because their intricate calculations would go on to help the RAF secure victory in the Battle of Britain – a triumph that many historians now believe changed the course of World War II. Bent together over their graphs, father and daughter concluded that the new generation of aircraft being built by the UK government to prepare for future war should be armed not with four powerful machine guns but eight – an idea was seen as deeply radical, even improbable at the time. Yet only then, the Hills had come to believe, would a new generation of Spitfires and Hurricanes have sufficient firepower to bring down enemy aircraft. A scientific officer in the UK Air Ministry, Captain Hill managed to convince his superior officers of the importance of his and Hazel’s findings – and six years later, in 1940, their calculations were put to the test in the skies above Britain as the RAF fought Adolf Hitler’s much feared Luftwaffe in a four month battle that has been described as the most important military campaign ever fought. The Battle of Britain is often referred to as the first major military battle which was fought entirely by air forces. Who knew that Reginald Joseph Mitchell’s iconic design could still be improved by a 13 year old girl from north London?