On the night of 16-17 May 1943, Wing Commander Guy Gibson led 617 Squadron of the R.A.F. on an audacious bombing raid to destroy three dams in Germany’s indstrial heartland, the Ruhr valley. From 9.28pm on 16 May, 133 aircrew in 19 Lancasters took off in three waves to bomb the dams. Gibson was flying in the first wave and his aircraft was first to attack the Möhne at 12.28am; alas five aircraft had to drop their bombs before it was breached. The remaining aircraft still to drop their bombs then attacked the Eder, which finally collapsed at 1.52am. Aircraft from the two other waves bombed the Sorpe but it remained intact. Of the 133 aircrew that took part, 53 men were killed and three became prisoners of war. The raid had limited success but gave a significant morale boost to the people of Britain.