It’s three-quarters of a century since 617 Squadron flew off to break open major German dams in a mission to hit Nazi Germany’s war production.

Commanding officer of 617 squadron, Wing Commander John Butcher with Johnny Johnson, the last survivor of the original Dambusters (Joe Giddens/PA)Commanding officer of 617 squadron, Wing Commander John Butcher with Johnny Johnson, the last survivor of the original Dambusters (Joe Giddens/PA)

The raid in May 1943 called for pinpoint accuracy in dropping bouncing bombs from the speeding Lancaster bombers, so the devices could skip over the dams’ defences in the water and strike the dam walls.

A modern RAF Typhoon in a commemorative flypast over the Derwent dam in Derbyshire (Danny Lawson/PA)A modern RAF Typhoon in a commemorative flypast over the Derwent dam in Derbyshire (Danny Lawson/PA)

Wing Commander Guy Gibson, who led the squadron, was killed on another mission later in the war, in September 1944. He was just 26.

Leader of the Dambusters raid Wing Commander Guy Gibson, with members of his Lancaster crew, (left to right) Pilot Officer PM Spafford, bomb aimer; Flight Lieutenant REG Hutchinson, wireless operator; Pilot Officer GA Deering and Flying Officer HT Taerum, gunner (Imperial War Museum/PA)Leader of the Dambusters raid Wing Commander Guy Gibson, with members of his Lancaster crew, (left to right) Pilot Officer PM Spafford, bomb aimer; Flight Lieutenant REG Hutchinson, wireless operator; Pilot Officer GA Deering and Flying Officer HT Taerum, gunner (Imperial War Museum/PA)

A total of 133 aircrew set out on the raid in 19 Lancaster bombers from RAF Scampton, led by Wing Commander Gibson, but 53 men were killed on the mission and three were captured.

PA GraphicsPA Graphics

The four-engine propeller Lancaster, which carried Barnes Wallis’s revolutionary bouncing bombs, was advanced for its time.

Commanding officer of 617 squadron, Wing Commander John Butcher with Johnny Johnson (Joe Giddens/PA)Commanding officer of 617 squadron, Wing Commander John Butcher with Johnny Johnson (Joe Giddens/PA)

Barnes Wallis was the inventor of the bouncing bombs which breached the Mohne and Eder dams in Hitler’s Germany.

Dr Barnes Wallis (right), in 1967, inventor of the ‘bouncing bomb’ which was used to breach the Mohne and Eder dams in May 1943, with the former Air Chief Marshal Sir Ralph Cochrane (PA)Dr Barnes Wallis (right), in 1967, inventor of the ‘bouncing bomb’ which was used to breach the Mohne and Eder dams in May 1943, with the former Air Chief Marshal Sir Ralph Cochrane (PA)

The name given to the Dambusters mission, in which today’s sole survivor Johnny Johnson was a bomb aimer, was Operation Chastise.

A Second World War RAF Lancaster bomber (PA)A Second World War RAF Lancaster bomber (PA)

The Lancaster bomber has often been seen flying in formation with two other RAF Second World War aircraft – the Hurricane and Spitfire fighter planes.

A Lancaster bomber, a Spitfire and a Hurricane in a Battle of Britain memorial flight (Peter Byrne/PA)A Lancaster bomber, a Spitfire and a Hurricane in a Battle of Britain memorial flight (Peter Byrne/PA)

The anniversary is a time for remembering those who made the ultimate sacrifice in the Second World War.

Flight Lieutenant Nigel Painter holds a wreath as he stands among 53 pairs of flying gloves at the Bomber Command Memorial in London’s Green Park which represent the men who died in the Dambusters raids (Kirsty O’Connor/PA)Flight Lieutenant Nigel Painter holds a wreath among 53 pairs of flying gloves at the Bomber Command Memorial in London’s Green Park. The glove pairs represent the men killed on the raid (Kirsty O’Connor/PA)