70 years ago, RAF Lancaster No.617 bomber squad. hit Germany’s Ruhr Valley dams. WWII Lancaster bombers at RAF Scampton on May 16, 2013 in Lincoln, England. Ladybower and Derwent reservoirs were used by the RAF’s 617 Squadron in 1943 to test Sir Barnes Wallis’ bouncing bomb before their mission to destroy dams in Germany’s Ruhr Valley. It marks the 70th anniversary of the famous Dambuster mission and will be watched by veterans from the original campaign. The 10k. lbs. bouncing bomb was referred to as an “upkeep” weapon.