"Perhaps the most famous RAF squadron currently flying, 617 Squadron was formed at Scampton on 21 March 1943 specifically to undertake one operation - Operation Chastise - the breaching of dams vital to the German war effort. The Squadron's Commanding Officer, Wing Commander Guy Gibson, was given free reign to comb other Lancaster squadrons for the crews he thought could best undertake the mission. For weeks, not even Gibson was told of the unit's task, only that low-level flying over water was essential, and training was undertaken in around the dams and reservoirs of Derbyshire. Chastise called for the breaching of three enormous dams in the Ruhr - the heart of German industrial production - by dropping a specially designed mine at exactly 60 feet (18.29m) and a speed 220 mph (354 km/h). Nineteen specially modified Lancaster carried out the attack during the night of 16/17 May 1943, successfully breaching the Mohne and Eder dams, butfailing with attacks on two others, the Sorpe and Schwelme. Wing Commander Gibson repeatedly flew over the Mohne and Eder dams to draw fire away from the attacking aircraft and was subsequently awarded the Victoria Cross for his gallantry. Thirty-two other members of the Squadron were also decorated but a total of eight aircraft and their crews were lost during the night.
The unit was retained to carry out highly specialised attacks, many of which employed the 12,000lb (5,448kg) 'Tallboy' and 22,000lb (9,988kg) 'Grand Slam' bombs. The Squadron received Lincolns in September 1946 and Canberras six years later with which the Squadron took part in Operation Firedog in Malaya before disbanding on 15 December 1955. On 1 May 1958, No 617 reformed at Scampton equipped with Vulcans, a type that remained on strength until 31 December 1981 when the unit disbanded. The following year, the Squadron reformed with Tornado GR1s at Marham, initially in the strike role, but latterly in the maritime strike mission based at Lossiemouth.
Number 617 continued to fly the Tornado GR1 until it was replaced by the updated GR4 and it was with these that the squadron carried out the first attacks with the RAF's stand-off weapon - Storm Shadow - during Operation Telic in April 2003.