In January 2016, at the age of 95, Lieutenant Commander David Balme died a hero.
Credited with capturing the top-secret Enigma machine that turned the tide of the deadliest war ever fought and thus shortening it by two years, he helped save hundreds of thousands of lives across the world.
As a sub-lieutenant on HMS Bulldog in 1941, Mr Balme led a boarding party on to the captured German submarine U-110, tasked with getting “whatever you can out of her – documents, books, charts, the wireless settings, anything like that."
U110 and HMS Bulldog
It gave the crew of HMS Bulldog a unique opportunity to discover the sub's complete contents, which included a wealth of intelligence material and an intact Enigma machine.
Faced with the unprecedented task of leading an Allied boarding crew on to a German U-Boat, the vulnerable lieutenant feared certain death as he had to holster his pistol while climbing down three sets of ladders to the control room. Should any submariner have chosen to wait in ambush aboard the Nazi sub, Balme was a sitting duck.
It was, he later recalled, “Terrifying. Going down those ladders and thinking there may be Germans ready to shoot you. We couldn't believe that they would have just abandoned this submarine.”
HMS Bulldog boarding team
He concluded: "I still dream about it sometimes, it was the most frightening moment of my life going down that U-boat"
Capturing the Enigma hardware marked a vital turning point in the Battle of the Atlantic. In the aftermath of Balme’s heroics, the cipher salvaged from U-110 played a significant role in cryptanalysis led by Alan Turing at Bletchley Park. The intact machine was used to break codes and intercept U-Boat ‘Wolfpacks’ with measurable success.
From when the machine became operational in June 1941, Allied shipping losses were around 432,000 tons. By August, this had dropped to less than 80,000 tons.
King George VI said the capture of the U-110 cipher material had been "the most important single event in the whole war at sea".
Despite this, Balme did not receive any recognition for his actions until the enforced secrecy surrounding Enigma relaxed in the Seventies. Prior to that, Bletchley Park and everyone attached to it was sworn to silence.
An original Enigma Machine at Britain's wartime code breaking centre, Bletchley Park
Since then Lt Cdr Balme has been recognised and presented with a Bletchley badge, alongside a certificate signed by Prime Minister David Cameron for his actions.
U-110 was the first of only three U-boats ever to be boarded by Allied servicemen during the war, and the episode provided a basis for the Oscar-winning film U-571, which reimagined the daring assault and boarding of U-110 as an American naval victory.
Despite Lt Cdr Balme’s sanguine defence of the film, screenwriter David Ayer admitted in 2006 that he “did not feel good” about altering the historical fact, suggesting the U.S rather than Royal Navy captured the naval enigma cipher.
Speaking to BBC Radio 4’s The Film Programme, Ayer conceded: "It was a distortion...a mercenary decision...to create this parallel history in order to drive the film for an American audience. Both my grandparents were officers in the Second World War, and I would be personally offended if somebody distorted their achievements."
Balme noted the film would not have been financially viable or reach as wide an audience as it did without being Americanised. He was pleased the credits acknowledged the Royal Navy’s role in capturing the Enigma ciphers, and glad the story had been told in tribute to all the men involved.