No single achievement by Royal Air Force Bomber Command is collectively remembered as vividly as the raids on the Möhne, Edersee and Sorpe Dams on the night of 16th May 1943. The unit responsible – 617 Squadron – became known as “The Dambusters” and in May 2013 commemorated 70 years since the raid. Ben Montgomery reports from the Derwent Reservoir.

Public imagination continues to be captured by “The Dambusters” in a way few other historic military events from World War Two do. Peter Jackson is currently remaking the 1955 classic “The Dam Busters” and media coverage in the run up to the anniversary events was extremely thorough.

Operation Chastise – “Busting the Dams”

Plans for destroying Germany’s Ruhr valley industrial facilities had been in place since before the start of the Second World War and it was estimated that to prevent the use of the heavy industrial facilities in the area would take 3000 Bomber Command sorties. It was conceded in July 1938 that whilst no weapons large enough were currently available, the possibility of a low level attack warranted further investigation.

Reconnaissance showed the Möhne and Edersee dams were protected by two booms, from which hung heavy anti torpedo nets. These would prevent any attack on the dams using torpedos meaning that a method of dropping a bomb with precision in front of the dam wall would be required, whilst also needing to ensure the bomb sank sufficiently before detonation to breach the dam wall.

Enter Dr (later Sir) Barnes Neville Wallis, an engineer working for Vickers-Armstrong (for whom he had helped design the Wellesley and Wellington aircraft). Dr Wallis, after researching methods of increasing cannonball impact force used by Vice Admiral Horatio Lord Nelson, believed that a bomb could be bounced over the torpedo nets at a low angle of incidence before sinking down the dam wall in much the same manner as skipping a stone.
The end result of Dr. Wallis’ efforts was the weapon known as “Upkeep”, a 9,250lb Torpex filled cylinder capable of travelling 400-450 yards over the surface of the water after having been spun up on a release mechanism attached to the bottom of a modified Avro Lancaster (the type being known as the Type 464 (Provisioning) Lancaster).

The mission to deploy the weapon was understandably secret, and even the Commanding Officer of the squadron Wing Commander Guy Gibson VC DSO(bar) DFC(bar), was unaware of the target for the first week of training. The initial training instructions were merely that the squadron had to practise low level flying at 100ft and 240mph, and it would be beneficial to do this over water.

Once the targets were revealed to be dams, navigators and bomb aimers were able to come up with their own sighting mechanisms that would allow the Upkeep weapon to be deployed at the correct height and distance from the dam. The height measurement device was two spotlights mounted at angles on the fuselage, which when flown at the correct altitude would form a figure of eight on the water surface. In practise, the weapon needed to be deployed from 60ft – slightly over half of the Lancasters 102ft wingspan!

The preparations for the raid on the dams came to a head on May 16th, the date on which the mission was to be flown. Crew members of each trade were taken for individual briefings throughout the day prior to all 617 Squadron crew being called to a major briefing in the afternoon during which the three targets were revealed.

19 Lancasters were to participate in the raid, flying in three individual waves. All flying was to be made at low level with increases in height allowed to 500ft only if absolutely essential to navigation. The first wave departed Scampton at 21:28, and the attacks began at half past midnight. Wg Cdr Gibson led the attack on the Möhne, which was eventually breached by the Upkeep from Flt Lt Maltby’s Lancaster – the fifth weapon to be dropped on the dam. The attack was confirmed as successful just before 1AM and the remaining aircraft detailed to attack the Möhne headed to the Eder dam. Despite being extremely misty, and having a more difficult approach path than the Möhne, the Eder was breached on the third attempt by Pilot Officer Knight’s crew in Lancaster “N for Nancy” ED912/AG-N.

The aircraft detailed to attack the Sorpe dam had less luck than the others on the operation. Flt Lt Munro and Pilot Officer Rice were both forced to return to Scampton with flak damage to Munro’s aircraft, and the loss of the Upkeep after hitting the sea for Rice. Pilot Officer Byers and crew were shot down over Holland, and Flight Lieutenant Barlow’s aircraft hit power lines and crashed with the loss of all onboard. Only Flight Lieutenant McCarthy was left to attack the Sorpe but whilst his Upkeep was successfully released, the dam was not visibly damaged. Of the five airborne reserve aircraft, only Flight Lieutenant Brown’s aircraft reached the Sorpe and he successfully dropped Upkeep on his sixth run, although again the dam was not damaged.
The last aircraft returned to Scampton at 06:15 on Monday 17th May 1943. Out of the 19 aircraft, 8 did not return to Scampton through a combination of enemy anti-aircraft fire and collision with low level obstacles.

Upkeep was never deployed again although 120 of the weapons were produced. Battle damage assessment of the raids was carried out by 542 Squadron, and it was later estimated over 1,600 were killed as a result of the Möhne dam breach alone.

As a tactical operation, Chastise never had the full effect intended. In the year prior to the attack, an emergency pumping system had been installed and by June 27th, full electricity production was restored. The Möhne dam was fully repaired by September 1943, and the Eder one month later but neither reservoir was permitted to hold its full capacity of water until some time after the war.

The attack was a very resource effective effort and the 19 Lancasters in the raid produced more cumulative damage than 586 aircraft had on a raid over Dortmund 11 days earlier. The success of the raid was amplified at home, with details being released to the media shortly after the event. 617 Squadron, despite being one of the newest in the Air Force, had cemented a solid reputation, and would go on to conduct more special missions including attacking and sinking the Tirpitz with Tallboy bombs alongside IX(B) Squadron.

70th Anniversary Commemorations

It is important to remember that the commemorations during mid May 2013 were to remember the anniversary of the attacks, and not the formation of the squadron itself. 617 Squadron was formed prior to the raid, on March 21st 1943 at RAF Scampton although due to the nature of their task, the squadron stood up in great secrecy.

617 Squadron did celebrate the squadron’s 70th Anniversary with the unveiling of two specially painted Tornado GR.4s – serials ZA412 and ZA492 – on March 21st. The aircraft tails are painted in a stylised version of the squadron logo showing a breached dam with three lightning bolts (signifying the Möhne, Edersee and Sorpe Dams), as well as profiles of their current Tornado aircraft, and the Lancaster Type 464 (Provisioning) aircraft used on the raids.

The Battle of Britain Memorial Flight, who fly one of only two airworthy Lancasters in the world, also used the anniversary as the basis for their latest repaint of PA474. Whilst authentically representing an aircraft used on Operation Chastise would be difficult due to the specialised modifications required to hold the Upkeep weapon, the BBMF selected to repaint PA474 in the colours and markings of DV385/KC-A (with nose markings of “Thumper Mk.III”), a Lancaster B.1 which re-equipped 617 Squadron after the dams raid. In this way, the aircraft could retain authenticity and still commemorate 617 Squadron.

The core of the 70th Anniversary events took place on Thursday 16th May, 70 years to the day since Operation Chastise. In the week leading to the anniversary, 617 Squadron deployed three of their Tornados (including both anniversary jets) down to RAF Coningsby from their regular home up at RAF Lossiemouth in Moray, Scotland.

Derwent Reservoir, and its accompanying dam, was used a practise location by 617 Squadron in the run up to Chastise due to the similarity of the dam’s construction with that of the dams to be targeted in the raid. It was only fitting therefore, that the 70th anniversary commemorations include flypasts over this significant location.

Timed to occur at 1300L, the event was to include flypasts from the BBMF Lancaster, two Spitfires and two Tornados from 617 Squadron. In the event, one Spitfire was unable to participate due to undercarriage problems on departure from its base at RAF Coningsby. The aircraft were to continue down the reservoir after their flypasts at Derwent to pass over Eyebrook Reservoir (used as a stand-in for the Möhne reservoir), and Chatsworth House, where the public were encouraged to gather to view the flypasts.

The Lancaster conducted one pass down the valley over the dam with the bomb bay open, before turning and flying up the valley in the opposite direction. The final pass was again down the valley, with bomb doors closed.

Spitfire PM631 accompanied the Lancaster in trail for the passes. There has been speculation as to why the Spitfire participated in what was a Bomber Command commemoration although in reality the Spitfire played an important role in Operation Chastise. Unarmed photo-reconnaissance versions, flying with the RAF Photo Reconnaissance Unit at RAF Benson, photographed the dams and proposed route in the run-up to the raid and provided post strike imagery in the aftermath. It was therefore appropriate that the Spitfire participating in the flypast, PM631, was a Photographic Reconnaissance PR.XIX version.

The Lancaster and Spitfire had previously flown over the dam during the 65th Anniversary of the squadron in 2008 so the 70th Anniversary and commemoration required something more special. Fulfilling this requirement were the two anniversary schemed 617 Squadron Tornados, flown from RAF Coningsby for the event. Flown as “Gibson Flight”, as reference to Wg Cdr Guy Gibson, the two Tornados were crewed by Flt Lt Stew Campbell(Pilot)/ Flt Lt Mahmoud Abdallah(WSO) and  Capt Erik Snel RNethAF(Pilot)/Flt Lt Chris Whitehair(WSO) in Gibson 1 and 2 respectively.

The celebrations for the day didn’t end at Derwent, with a full service being conducted at RAF Scampton that evening. As well as serving members of 617 Squadron, the service was attended by two of the last three surviving members of the raids – Sergeant (later Squadron Leader) George “Johnny” Johnson, and Flight Lieutenant (later Squadron Leader) Les Munro.Sergeant Fred Sutherland (Royal Canadian Air Force) unfortunately had to remain in Canada due to his health. 617 Squadrons commander, Wing Commander David Arthurton was determined to show Fred that the Squadron had not forgotten him – and as such intended to visit him during the planned deployment to Alaska for Red Flag. Unfortunately, US Government sequestration put paid to the exercise, and thus 617’s plans. Hopefully Fred was able to view the service from his home in Canada. Broadcast live on the BBC, the event included drill from the Queens Colour Squadron, and music from the Central Band of the Royal Air Force. Both Tornados, the Lancaster and two Spitfires were in attendance overnight at Scampton – returning to RAF Coningsby the following day for a flypast over Lincoln Cathedral.

The commemorations ended on Sunday 19th May, with a further flypast for the dedication of a new memorial for 617 Squadron at Woodhall Spa, remembering all those who served on the Squadron and gave their lives whilst serving with the Royal Air Force. This memorial is in addition to the current memorial which commemorates the 53 airmen who did not return from Operation Chastise.

The entire commemorative event was one of the more impressive of recent years, and brought the Dambusters firmly into the public spotlight again. For all intents and purposes, the men and women of 617 Squadron, and the Battle of Britain Memorial Flight, did justice not only to themselves but also to those who gave their lives in service to the Crown – both on Operation Chastise, and in the Second World War as a whole.

Après moi, le déluge!

If you wish to support the Dambusters, we’d recommend heading over to and purchasing yourself some collectables – some proceeds of which will go twards the Leonard Cheshire Disability Charity, the 617 Squadron 2013 Charity.