The Men Who Breached the Dams

Posted on Thursday 9th May 2013

By Alan W Cooper, extracted from The Men Who Breached the Dams and reproduced by permission of Pen and Sword Books Limited.

The concept of an attack on the German dams in the event of a Second World War was first discussed by the Air Ministry's Bombing Committee in 1938. This committee had been formed in the 1930s to study and assess how Great Britain could hit, damage or destroy vital German targets, targets whose loss would have a severe effect on Germany's ability to wage war.

Many targets were suggested, listed, discussed and agreed upon. Many of them could be attacked by conventional bombing; others, of a more difficult nature, would need specialized treatment. One of the latter, discussed in committee on 26 July 1938, was the dams situated in South Westphalia. The objectives were clear:

(a) Cut off essential supplies of water for industrial and domestic purposes.

(b) Cause flooding and damage to industrial plants, railways, waterways, etc, in the river valley.

Only eleven days earlier, on 15 July, the economic and strategic importance of these dams was discussed by the Plans (Op) Operations at Air Ministry. The dams were:

(1) The Mohne – situated in the Mohne Valley south-east of Dortmund, whose role was to collect rainfall to prevent winter flooding and to provide power for electrical generators. Of utmost importance was the part it played in sustaining the underground water supply vital for industrial and household supplies.

(2) The Eder – situated south of Kassel and south-east of the Mohne. It was built to act as a reservoir for the important Mittelland Canal that runs from the Ruhr to Berlin. It also prevented flooding of farmland in winter and finally served hydro-electrical power stations.

(3) The Sorpe, Ennepe and Lister dams – situated south of Dortmund and south-west of the Mohne. The roles of these dams were similar to that of the Mohne.

Copy of an original drawing showing the principle of the bouncing bomb.

In total there were seven dams in South Westphalia, but the Mohne, Eder, Sorpe and Ennepe were considered of prime importance. The destruction of the one outstandingly important Mohne Dam alone with the massive loss of hydro-electric power, would have serious repercussions on the production output from the Ruhr, Germany's major industrial area.

The most favourable time for an attack upon these dams would be after a period of heavy rain when the reservoirs were full. Nevertheless, although flooding would not be so severe if the dams were breached during a dry period, a serious and immediate shortage of water would result. However, it had to be borne in mind that the destruction of the dams would be more difficult at low water. Yet, if the Mohne Dam, holding some 130 million cubic metres of water, was breached, the force of water flowing down in the Ruhr Valley in a few short hours would be so powerful that villages and towns as well as waterways in the Ruhr Valley, as far as the Ruhr itself, would be swept away and destroyed. The entire area's population of between four to five million would be without water, and the mines and coke plants paralysed owing to a lack of industrial water supply.

However, although the dams presented a valuable target, a method of destroying them was far from straightforward. Normal bombing would hardly chip the huge structures and if a torpedo like weapon were developed, surely the Germans would protect the dam walls by using anti-torpedo netting. So, the dams, recognized as important targets, remained on the Air Ministry's list.

the night of the attack - 16/17 may 1943

At 5 Group Headquarters Operation's Room at Grantham, Sir Arthur Harris and Ralph Cochrane had been joined by Barnes Wallis, who had come straight from Scampton. Wallis immediately asked if there was any news. 'Apart from a flak warning from Gibson, nothing at all,' answered Cochrane.

One wall was dominated by a blackboard listing the aircraft taking part in the attack. On a dais alongside the opposite wall sat the operations officer who was in telephone contact with the radar room. Then from Gibson came a signal to Group, using the pre-arranged code; 'Goner – 68A time 00.37.'

The number '6' signified Special Weapon released and exploded five yards from the dam. The '8' meant no apparent breach seen. The time was the timing of the signal. This signal was received by Wally Dunn, who said to Harris, 'Sir, there is a signal coming in. It's from Gibson's aircraft; it says, Goner – bomb released and exploded five yards from the dam, no apparent breach. That's all.'

Nothing was said. Everyone keeping his thoughts to himself.

The flak gunners on the dam were not the only ones to realise that the dam was the target, another being the foreman of the power station below the dam, Herr Clemen Kohler. He heard from a lookout at 00.20 of the arrival of possible hostile aircraft. He suddenly realized that this was a night of a full moon, a night when the Royal Air Force did not usually venture over the Reich, and he also realized that the water level in the lake was higher than it had ever been before. He telephoned the United Electricity Company of Westphalia's Office at Neheim, a little town just down the valley. He told them he thought the RAF were attacking the dams, but he wasn't believed, so he put down the phone, opened the door to the outside and looked out. As he did so, Gibson's Lancaster flew overhead with all guns firing, then came the explosion and water began spilling over the dam wall high above him. Kohler began to run and didn't stop until he reached the side of the valley several hundred yards away. He then dropped down beneath a tree halfway up the slope where he looked back down to see if the dam was still intact. With some relief he saw that it was.

Gibson waited for the water disturbance to subside before calling up the next aircraft – Hopgood's damaged M-Mother. An additional value of Gibson's first run was that he was able to gauge the barometer pressure over the water at the prescribed height. Also judging the strength of the defences which seemed to amount to some fifteen guns, situated not only in the towers but on the banks on either side of the dam. Gibson said to Hopgood: 'Take over M-Mother. Good Luck.'

Tony Burcher in the rear turret of Mother had watched Gibson's attack as they circled around waiting either a result or a turn at attack. All he could think of was, let's get it over and get back! Hopgood called back to him, 'Stand by, rear gunner, they are putting up a barrage ahead.' Gibson continued to circle, drawing off some of the fire from Hopgood. He saw Hoppy's spotlights go on over the water and immediately attract all the fire power the Germans could muster; they were not going to be outdone this time.

Karl Schutte, a member of the SS Flak Unit based at the dam, was on duty in the north tower and remembers: 'Target change, new inflight. It roared towards us like a beast as if it would ram the tower and us. One did not think of the danger, at last we could fire. I stood behind the gunner adjusting the gun height and making corrections, at the same time adjusting the side directions. We fired – whatever the gun would give. The shells whipped into the face of the attacker.'

Burcher heard the shout from navigator Ken Earnshaw to 'Go lower, still lower!' as he watched the two spotlights join up. He then heard, 'Bomb gone!' from Fraser. Just at that moment there was a terrific crash and Burcher saw flames streaming past his turret on the port side.

Sergeant Brennan, the engineer, shouted: 'We're on fire, port inner engine.'

'Press the extinguisher and feather Number Two engine,' commanded Hopgood.

This worked for a second or two but then the fire relit itself. With the port outer already dead and now the port inner blazing, Hopgood had very few options open to him at this low height. Instantly he gave the order to prepare to abandon the aircraft.

While this was going on the bomb was bouncing towards the dam, but it had been released just a fraction of a second too late. In his rear turret, Burcher tried to swing his turret around, using the dead-man's handle to slowly hand crank it to the fore and aft position. He recalls doing this in record time as his parachute was inside the fuselage behind him and he could not reach it until the turret was in the correct position. Managing this, he pressed the door release, scrambled out and grabbed his 'chute, clipping it to his chest. He then plugged into the intercom.

'How are you doing up front?'

Hopgood yelled back, 'Get out you bloody fool. If only I had another 300 feet – I can't get any more height.' All this took place in about 25 seconds after passing over the dam wall.

The flak gunners on the dam gave a shout, 'It's on fire', as they saw their guns hit home and the aircraft catch fire. An eye witness saw the bomber fly over the dam followed by a giant mushroom of foam in front of the wall. Seconds later the detonation reached them, and the pressure was so great the watchers were flung from their open door. Suddenly a flame came from the bomber and looking like a giant torch it flew over the town of Haar, disappeared, and was then heard to crash. The bomb, meantime, had bounced over the wall of the dam and exploded, completely destroying the power station. The explosion knocked the flak gunners off their feet, and seconds later nothing was left of it.

'The firing was good,' continues Karl Schutte. 'The plane burned and I shouted to my gunner and then came a crack – dust took our breath away. Strong pressure threw me to the ground and stones flew about our ears. The power station stood no longer. A quick glance at the burning plane; a strong explosion confirmed our success, but we had no time to look around for the hot, glowing gun barrel needed changing and a quick oiling. Apart from the directional gunner and munitions loader, everybody was replenishing the magazines since practically all the shells had been fired. Everyone did his best. Suddenly a report came from Tower Two - "Out of Action" - the impact had flung it into the plinth.'

Hopgood's Lancaster crashed three miles to the north-west, near the village of Ostonnen, which is five miles west of Soest. It burst into flames killing all the crew left on board. As Hopgood struggled to keep it in the air in order for his men to get out, Burcher saw the wireless operator, who had been wounded over the coast on the way in, dragging himself the length of the fuselage towards the rear hatch. John Minchin's face was white with pain, his leg had been nearly severed. He had sat with this terrible injury for the past hour. All Burcher could do to help was to clip on Minchin's parachute and push him out into the darkness. As he did so, Burcher pulled Minchin's D-ring release, but he did not see if the parachute opened, although witnesses did see two parachutes deploy.

Burcher then pulled his own parachute release while still in the aircraft. He knew it was not in the text books, but at this height he felt it was his only chance. Bundling it under his arm he plugged in the intercom for the last time.

'Rear gunner abandoning aircraft,' he yelled.

Hopgood yelled back, 'For Christ's sake get out of here!'

At that moment there was a terrific bang and a great rush of air. The flames had reached the main wing fuel tank. Burcher was blown out and smashed into the tailplane so violently that he broke his back. To this day Tony Burcher still has a hollow in his back and the break can be felt and still seen on X-ray. He landed with a terrific thud, which was only to be expected at such a low height. As he hit, the parachute billowed and took him back up again and this, a German Medical Officer said later, was what saved him. Landing again he lay stunned, hearing the other aircraft overhead and the ground vibrating beneath him. Dan Walker, Shannon's navigator, had watched Hopgood's aircraft go down and was amazed to learn that Tony Burcher had survived. The Lancaster, he said, seemed to speed itself along the ground in flames.

Hopgood's crashed Lancaster still smoulders whilst a German officer inspects the wreckage.

Gibson spoke to Martin, ordering him in for his attempt on the dam. As Martin began his run, Gibson flew his aircraft alongside Martin's to help divide the fire power coming from the guns. Martin was hit several times, having his starboard outer fuel tank and ailerons damage – luckily the tank was empty at this time. The front gunner, Tony Foxlee, was returning fire with his two guns, while Tammy Simpson in the rear, sprayed them as they passed. Martin was later to praise the work of both gunners, as well as the rest of his men in the wonderful show they put up. He was also grateful to Gibson, and the way he helped draw off enemy gunfire. Martin's bomb went down at 00.38 although there was still a good deal of smoke from the demolished power station still in the air. The number of bounces could not be seen but there was another huge water spout, the ripples spreading out with a huge wave spilling over the dam wall.'

Karl Schutte: 'Now there were only two small guns to fight the beasts. The engine noise came nearer again. Banking planes dropped more flares and also showed their directional lights to draw our fire. We restarted firing which was returned by the machines. While they still tried to draw our fire, another plane raced towards the wall. Target change, and again the shells whipped towards the attacker and several hits were scored, but what could our 2 cm guns do against an armoured flying fort, it was just scoring good luck hits. The plane was now also shooting at us. Just like a string of pearls, the luminous spur of the shells came towards the tower like large glow-worms.

'Then a heavy explosion and a great water spout, and again the lake quaked and mighty waves engulfed the wall. We did not know whether the wall was still standing, we must only fire and fire again. Then came the fourth attack and the picture was repeated but we didn't know which machine to fire at first. This attack too was unsuccessful. Could we do it, would we fight them with our barking guns and foil the attack? We hoped no other guns would be put out of action, since the three guns of the 2nd Unit were down in Gunne and could only fire on machines veering away, since the attack was only coming from the lakeside.'

The fourth aircraft Gibson ordered in was Dinghy Young's. He came in low, dropped his bomb at 00.40, while his gunners exchanged fire with the men on the dam. Once again the bomb bounced against the wall correctly and the now familiar water spout erupted and a huge wave of water spilled over the wall. Young yelled to Gibson that he thought the dam had gone, but Gibson looking down, replied, 'I think it will take one more bomb.' Young sent his message back to base at 00.50, code 78A – weapon release and exploded in contact with the dam wall, no breach seen. Mick Martin, who had bombed earlier, did not send his message back until 00.53 – code 58A, spun weapon, released, exploded 50 yards from dam, no apparent breach.

J-Johnny with Dave Maltby was next. This time there was no flak fire from the dam. Karl Schutte continues:

'Some machines were firing at us from the valley end and we replied, but then the gun failed – the lock was stuck. We tried desperately to remove the cause and even tried sheer force, but without success. A premature shell had damaged the housing. It was hopeless. We stood high on the tower, in front of us the lake and behind the valley. Attacked from all sides we could not defend ourselves. We waited literally for the end.

'Then a fifth plane started its attack. Only the gun on the lower wall was still firing. The machine neared the wall at an incredible speed; they now had an easy game – I could almost touch it, yet I think even today I can see the outline of the pilot. With our gun silent we did that which we had drilled so often – defence with rifles!'

Maltby's bomb was again on target and the water flew into the air. When it cleared a hole could be seen in the dam and getting bigger by the second. In fact Maltby had seen a minor breach in the dam on his run-in so it appears that Young's bomb had started the ball rolling. Maltby's wireless operator called base at 00.55 am, code 78A – weapon released, exploded in contact with the wall – no apparent breach.

Suddenly the water was rushing down the valley and the air was full of spray. At this precise moment, Gibson was flying around and could not see the explosion owing to smoke, and spray settling on his windscreen. Time was now getting short. He was about to order Dave Shannon to make his run when he saw a large hole in the dam and water pouring out. 'It has rolled over!' he yelled, then ordered Shannon to break off and not to attack. Taking a closer look, he saw a breach of 150 yards in the dam wall.

The men at Grantham were tense. What was happening? Would it work? They had just had the message from Maltby saying 'no breach', and he was the fifth to attack! Little was said. Undoubtedly Wallis was making and remaking mental calculations, his instincts saying it must work but his ears hearing messages saying it was not.

At 00.56 am Gibson sent a message with the pre-arranged code word 'Nigger'. Wing Commander Dunn began to take down the signal. He got to 'N-I-G ... ' and bellowed out at the top of his voice, 'Nigger!' Harris dashed to Wallis and shook his hand, patting him on the back, and said, 'I knew it would work.' At 00.57 Group replied to Gibson on full transmission, asking him to repeat his signal. Gibson did so with one word.

'Correct.'

On the dam Karl Schutte watched in horror. 'Again the lake quaked and a gigantic wave came over the wall. The wall had been breached and relentlessly the water began to run into the valley. The planes banked away.'

Leutnant Freswinkle had also been on the dam, and had given orders to his gunners to fire sustained automatic fire through all the apertures in the tower and wall, but it had all been to no avail.

Gibson circled for three minutes and then called up the other Lancasters, ordering Maltby and Martin back to base. This they did, landing back at 3.11 and 3.19 am respectively.

Tony Burcher was still lying stunned on the ground. He looked towards the dam to see a great column of water. It went up like a giant soda syphon, followed by a roaring sound. He thought, 'I'm going to be drowned.' He was, of course, over a mile away but in his his shocked state this did not register.

The power station foreman, Clemen Kohler, was still sitting beneath the tree, and watched as the masonry bulged then burst between the two towers. The first rush of water plunged down to the bottom of the valley, striking the ground with a colossal crash. The remains of the power station vanished in a second and the tidal wave settled in one gigantic rush, pouring down the valley at twenty feet per second, taking everything with it. Further down the valley, car headlights changed colour as the water overtook them.

The Mohne Dam had been smashed.

The Mohne Dam after the raid.

'One did not think of the danger, at last we could fire. I stood behind the gunner adjusting the gun height and making corrections, at the same time adjusting the side directions. We fired - whatever the gun would give. The shells whipped into the face of the attacker.'

(Karl Schutte, SS Flak Unit)

Karl Schutte stands at the back of the anti-aircraft gun on the Mohne Dam.

'Hopgood had very few options open to him at this low height. Instantly he gave the order to prepare to abandon the aircraft. While this was going on the bomb was bouncing towards the dam, but it had been released just a fraction of a second too late.'

John Hopgood DFC.

Flying Officer Gregory.

Tony Burcher, the only survivor from Hopgood's crew.

The fourth aircraft Gibson ordered in was Dinghy Young's. He came in low, dropped his bomb at 00.40, while his gunners exchanged fire with the men on the dam.'

Karl Schutte wearing his Iron Cross.

'Again the lake quaked and a gigantic wave came over the wall. The wall had been breached and relentlessly the water began to run into the valley. The planes banked away.'