Dambusters departing B&W version

Lincolnshire, shortly after sunset on 16 May 1943: Wing Commander Guy Gibson, flying AJ-G ("G - George"), ED932/G, leads the first wave of specially adapted Lancaster bombers of 617 Squadron on their way to attack the Ruhr dams with Barnes Wallis's "bouncing bomb".

Flying with Gibson were John Hopgood in AJ-M, ED925/G and Harold Martin in AJ-P, ED909/G. Hopgood and most of his crew were killed that night attacking the Mohne dam.

The secret weapon - actually a type of depth charge - was designed to ricochet across water over the defensive torpedo nets and sink next to the dam walls before exploding.