The number 617 Squadron is a Royal Air Force (RAF) aircraft squadron, originally based at RAF Scampton in Lincolnshire and currently based at RAF Marham in Norfolk. It is commonly known as the ''Dambusters'', for its actions during 'Operation Chastise' against German dams during the second World War. The attack was carried out on 16-17 May 1943 using a purpose-built 'bouncing bomb' developed by Barnes Wallis, who was an English scientist,engineer and inventor. Sir Barnes Neville Wallis born 26th September 1887, was a pioneer of geodetic airfame construction and a leading figure in British aeronautical and aerial warfare design. The Air Force accepted Wallis's bouncing bomb after some initial scepticism.

The 'bouncing bomb' was used in the 'Operation Chastise' to attack all three dams of Ruhr Valley. The Ruhr is a river in the Western Germany, a right tributary of the Rhine. The Ruhr area was Germany's primary industrial area during the early to mid-20th century. The occupation of the Ruhr, from 1923-24 was by French forces. The special 'bouncing bombs' were developed to take out the dams and flood the valley. The Mohne and Eder dams were breached,causing catatropic flooding of the Ruhr Valley and of villages in the Eder Valley; Sorpe dam sustained only minor damage.

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