75 years ago Derbyshire became a practice site for World War Two’s most daring flying raid. Viv Micklefield travels to the Upper Derwent Valley, for many the spiritual home of the legendary Dambusters
These days, a walk or cycle beside the Derwent Reservoir provides a chance to unwind, to let the mesmerizing Dark Peak views lift the spirit. Yet the glassy expanse of water so dramatically reflecting the scudding clouds and densely wooded slopes, holds a story that’s gone down in the annals of wartime flying folklore. Because it’s here, just 60 feet above Derwent’s soaring gritstone dam wall flanked by its iconic Gothic towers, that the men popularly known as ‘The Dambusters’ perfected their hair-raising skills.
Rewind to March 1943, and shrouded in secrecy, the RAF’s Bomber Command assembled the elite 617 Squadron charged with carrying out an audacious night-time mission to disable Germany’s industrial heartland. Code named Operation Chastise, the plan was to attack and breach three great Ruhr Valley dams: the Möhne, the Eder and the Sorpe. Led by flying ace Wing Commander Guy Gibson, the crews who’d been chosen for their prowess and ‘press-on spirit’ had just two months to prepare for delivering Barnes Wallis’s famous ‘bouncing bomb’. The Ripley-born inventor had designed his revolutionary device – in reality a spinning mine, to skim the water and explode at the bottom of the dam wall, but only if it could be dropped at the right height, at the right speed and at the right distance from its target.
‘They weren’t told until the last minute that the raid was on dams but they did know that the target involved water,’ says Dave Ashton, manager of Fairholmes Visitor Centre and a veteran of military flying. Dave continues: ‘Derwent Valley Water Board gave permission to use the reservoir as a practice bomb site, although the training wasn’t exclusively here; they used whatever stretches of water they could find including canal locks and the sea, and they flew and flew until they got the knack of flying lower and lower.
‘We still get Hercules transport planes and fast jets coming over today, but these are much easier to fly at low level than the Lancaster they used,’ he observes.
Dr Robert Owen, 617 Squadron’s official historian, points out that Gibson’s own memoirs suggest one of his first exploratory forays was over the Upper Derwent Valley. Following a short flight from their airbase in Scampton, Lincolnshire the former Bamford church tower acted as a navigation marker before he would swing round for the approach run. Converging beams from spotlights on the plane’s nose and tail were used to gauge the height above the water; whilst the Derwent Dam’s twin towers, if lined-up with two vertical pointers on a simple sighting device, told the pilot when to take aim and release the mine.
‘Gibson’s first run was in daylight and he did another one at dusk with the industrial haze floating across from Sheffield. The squadron was formed on the 21st March and the raid was in mid-May, meaning there was only one period of full moonlight. So in order to simulate this, they took a system already in existence that involved the cockpits having a blue Perspex filter attached and when the pilot wore amber goggles those two colours combined to create the effect of moonlight.
‘Whether all the pilots had an opportunity to practise over Derwent is not known for sure, but I suspect they did,’ says Dr Owen. He adds: ‘Most likely they went over as single craft, possibly in twos but not in formation. The final attacking speed was 220mph so if you look at the length of the Howden and Derwent Reservoirs, there’s not long to cover them.’
Nevertheless, even for this sparsely populated rural area – 12 farms were sacrificed in the building of the Derwent Valley’s oldest reservoirs 25 years earlier – with many of the residents either having joined-up to serve or migrated to inner city munitions factories, for those remaining the ear-shattering interruption to their peace and tranquillity was a reminder of the dark days of war.
Whilst engine vibrations reportedly loosened roof tiles, accounts followed of falling milk and egg production, and a Mrs Cotterill, who lived on the water’s edge, expressed her worry that ‘the poor boys’ were flying around in ‘old’ planes.
‘The aircraft used for the raid had specially modified bomb-bays,’ explains Dr Owen. ‘When the squadron was first formed those aircraft were still being built, so they started training with standard Lancasters. Modified craft started arriving from April 1943 and I suspect they would have been able to use these ahead of the operation.’
For two of 617 Squadron, their training must have held a special significance. Flight Lieutenant Bill Astell DFC described by Gibson, his commanding officer, as ‘a grand Englishman from Derbyshire’ came from the village of Combs. Meanwhile, down the road in Chapel-en-le-Frith, lived Sergeant Jack Marriott DFM, the flight engineer in Squadron Leader Henry Maudslay’s crew.
It is, observes Dr Owen, a coincidence of war. ‘I’m not sure they knew each other prior to the squadron being formed. Marriott was from a farming background and went to the local school, whereas Bill Astell’s father was a director of a Manchester cotton company and he went to public school.’
For all of the 133 airmen, their training culminated on the night of 16th/17th May when 19 Lancasters left Scampton bound for the Ruhr. Both the Möhne and Eder Dams were successfully breached and hits made on the Sorpe and Ennepe Dams. However, a heavy price was paid. Only 11 aircraft made it back, with 53 airmen killed including Astell and Marriott, with a further three becoming POWs.
History records that whilst Operation Chastise may not have achieved a knock-out blow to the German war effort, it was a real morale booster to those back home. And, Dr Owen believes, as a result, people woke up to the fact that dams here were potential targets.
‘Following the raid there was quite a lot of activity to protect British dams. Initially, they put in temporary anti-aircraft guns and later these were replaced by smokescreens. During that period, 617 Squadron provided data and information on where best to locate them. It was certainly a legacy.’
Although the Derwent Dam’s only permanent memorial to its association with 617’s heroics lies beneath the west tower, as Dave Ashton says, the sight of a vintage Lancaster, its four Rolls-Royce Merlin engines echoing down the valley is a real crowd-puller: ‘At least 20 per cent of our visitors come for The Dambusters story, they are so intrigued by it. And if they know the Lancaster is coming over, you can guarantee caravans will be parked up in the days before.’
Fact-file
The Derwent Reservoir’s towers follow early 20th century architectural fashion but also reinforce the structure of the dam wall.
The Dam Busters film was released in 1953, ten years after the raid, but the bouncing bomb’s shape was disguised as it was still on the Official Secrets List.
Wallis was a life-long pioneer, also designing airships, fixed-wing aircraft, munitions, and post-war contributed to the development of super and hyper-sonic flight.
617 Squadron’s motto is ‘After me, the flood’. Since Operation Chastise they’ve also flown Vulcan, Tornado, and stealth aircraft. Their 2018 base is RAF Marham in Norfolk.
