The legendary tale of The Dambusters, immortalised in film, has gone down as one of the most spectacular missions in the Royal Air Force's history and one which helped turn the tide of the Second World War.
The Dambusters conducted a night of raids with Sir Barnes Wallis's revolutionary bouncing bombs, releasing them 60ft above ground, on German dams in May 1943.
Of the 133 airmen who left on the missions, 53 did not return, giving a survival rate of just over 60 percent.
Operation Chastise, as depicted in the 1955 hit film The Dam Busters, saw some 19 Lancaster bombers fly from RAF Scampton in Lincolnshire for the daring mission over the night of May 16 and May 17 1943 to destroy dams in Germany's industrial heartland and cut off vital supply lines in the Ruhr Valley.
Former RAF Officer John Nichol, who was shot down and taken prisoner during the Gulf War, has written a book detailing what The Dambusters, or more specifically 617 Squadron, did next. John spoke to Forces Radio BFBS presenter Hal Stewart about the most iconic mission in the Royal Air Force's history:
"They went on to an illustrious career post the dams operation, but not many people know what they did."
This May on the 75th anniversary of the mission, the classic 1955 film, which has been re-versioned into 4K, will be screened across the UK.
There will also be a special gala screening at the Royal Albert Hall in May, and in 300 cinemas across the UK, where historian Dan Snow will be hosting the event.
Back in February, Forces News reporter Charlotte Banks went to meet Dan Snow when the reconstructed cockpit of a Lancaster Bomber was parked outside the London venue.
A total of 133 Allied aircrews left for the raid aboard 19 Lancaster bombers, led by Wing Commander Guy Gibson, but 53 men were killed and three were captured.
The Lancaster was 69 feet 4 inches long (21.11 metres), 102 ft wide (31.09 m) and 20 ft 6 in tall (6.25 m); it could reach speeds of up to 200 mph (322 km/h) on it's four Rolls-Royce Merlin V12 engines.
The aircraft had an impressive lifting capacity. Weighing 36,900 lbs empty (or 16,738 kg), it was able to haul an additional 33,100 lbs (or 15,014 kg) in fuel and bombs.
Crews then did without modern computerised equipment and had to calculate using maps, compasses, pencils and rulers, flying in a World War 2 sortie was akin to taking "a seven-hour maths exam in the dark while being shot at" according to Channel 4's 'The Dambusters'.
These difficulties were intrinsic to all bombing missions, though, for the pilots of Operation Chastise, the Dambusters raid had the additional challenge of having to be flown a mere 100 feet off the ground to avoid radar.
'The Dambusters' mission was made possible by the ingenious design of the bouncing bomb by Sir Barnes Wallis.
By using bouncing bombs the allies could avoid the torpedo nets protecting the dam by bouncing the bombs on top of the water to reach the target.
However, to get the bounce just right, the Lancaster bombers needed to approach the dams flying just 20m above the water while travelling at 230mph.