As the first of 20 modified Avro Lancasters arrived at RAF Scampton on 8th April 1943, the specially assembled volunteer crews of specialist 'Squadron X' (later allocated the RAF squadron number 617) from within 5 Group Bomber Command must have been intrigued. The new aircraft were B.III (Specials), referred to at Avro's Woodford factory as Lancaster Type 464 Provisioning and each one had been modified with equipment to deliver the Vickers Type 464 'Upkeep' mine.

As more Lancaster's arrived, the commander of this new squadron, Wing Commander Guy Gibson, selected Lancaster ED932/AJ-G as his own aircraft, due to the fact that the bomber's codes were the same as his father's initials, Alexander James Gibson. Gibson and the crew of ED932 were amongst the first to train with their new aircraft and their unusual bombs, releasing their mines at a test site at Reculver on the north Kent coast from May 12 1943, just five days before crews embarked on their historic raid. After a period of intense training and on the day prior to the raid, Gibson was finally briefed on the intended targets - 'Operation Chastise' would be striking at the industrial heart of Germany, the great dams of the Ruhr Valley.

At 21.39 on May 16 1943, Gibson and Lancaster ED932 took off from RAF Scampton at the head of the first attack wave of nine Lancasters heading for the Mohne Dam, flying a route over Suffolk, then the North Sea, crossing the Dutch coast at Zeeland, before heading inland attempting to avoid known areas of Luftwaffe defences. As Gibson and his crew made their attack run on the Mohne Dam, the other Lancasters of the first wave circled the target area, watching the effectiveness of the attack run and waiting for the instruction to commence their own attack. Having released their mine, Gibson and his crew flew alongside the other aircraft during their attacks, attempting to draw enemy fire away from the attacking aircraft, giving them the best chance of effecting a breach. The fifth mine dropped was a perfect run and exploded in exactly the right place to cause the already weakened dam to fail – they had done it.

In the years which followed, this incredible operation was referred to as the 'Dambusters Raid' and 617 Squadron would become one of the RAF's most famous units. 'Operation Chastise' was heralded as a spectacular success for Bomber Command, but at a heavy cost, as eight Lancasters and 53 airmen failed to return.

617 Squadron continues the proud legacy of the Dambusters airmen to this day, as the first operational RAF unit equipped with the Lockheed Martin F-35 Lightning, symbolically officially reforming in April 2018, the month in which the Royal Air Force commemorated its centenary.