CRACKING THE GERMAN DAMS

Korero (AEWS), Volume 2, Issue 7, 10 April 1944, Page 30

CRACKING THE GERMAN DAMS

By

Wing Commander Guy

in the Atlantic Monthly, December, 1942

The !■ lak over France wasn’t bad. It was coining up all around in spasmodic flashes as some straggler got

off his course and struggled through a defended area. Otherwise the night was lovely. There was a three-quarter moon which shone brightly into my Lancaster, lighting the cockpit up almost as if it were day.

I was feeling pleased because this was going to be my last raid before going on a few days leave ; for now I had done 173 sorties without having had much rest. It was almost too good to be true that after this raid on Stuttgart I should be able to go down to Cornwall with my wife and have the time of my life.

We dropped our load, and my poor Lancaster on its three engines jumped into the air as the bombs fell out of its belly and I banked around and dived for the deck.

During these moments there had been little talk, but once we were clear of the target area all the boys on board started talking.

“ Leave to-morrow.’

“ To-morrow we go on leave.”

“ I’m going fishing.” “ I’m going to sleep.”

“ To-morrow we go on leave.” “ Report to C. in C. immediately.” It was early when I was waked up and given this message.

The Air Marshal was very nice to me, and as I went into his room he said, “Hello, Gibson. Sit down.” Then he told me quietly that I wasn’t going to have any leave. He told me that I was to form a new squadron, a special squadron picked out of the best crews in the Bomber Command, the squadron which would have to undertake a most important mission. He told me that if this mission was successful, we should have succeeded in dealing to Germany in one night the most damaging blow of the war. He spoke to me about the Mohne Dam and about the Eder Dam. He spoke to me for a long time and told me of their importance and of the difficulty which we should have in destroying them. It took me an hour to pick my squadron I wrote the names down on a piece of paper and gave them to a man with a a red moustache who was sitting behind a huge desk. Then I got in touch with my wife and told her that our leave was postponed because I had one or two things to do before I could get away Next morning I got them all together. There were 25 crews, which means 175 men — navigators, wireless operators, bomb-aimers, engineers, and gunners,

and every one of them an old hand at the game.

My speech to them was short. I said : “ You’re here to do a special job. You’re here as a crack squadron. You’re here to carry out a raid on Germany which will have tremendous results. What the target is I cannot tell you, nor can I tell you where it is. All I can tell you is you will have to practice low flying all day and all night until you know how to do it with your eyes shut.” Then I went down to London, and there I met a man of whom I shall say very little. He was as much responsible for the success of this operation as all the pilots and air crews put together. He is one of the real backroom boys of whom little can be told until after the war, and even then I am not sure that you will hear a great deal of their story. ■

We met together in a small, dark office. He pulled out a drawing and gave me a short lecture on the science of damnology —which is, of course, the science of breaking down dams.

He said : “ Now you may think me a stupid old man, but wait until I tell you what I know about the Mohne Dam. It is a military objective which I have been studying ever since the war began. This dam ” —and he pulled out some pictures—- “ is some 850 yards long, 150 feet thick, and it is as high as it is thick. You can imagine that many attempts hdve been made,” he went on, “ to try to evolve some method of breaking down these walls, but it is not so easy as it looks. When you consider that we in London here think ourselves safe from an ordinary explosive bomb when we are behind 3 ft. of concrete, you will begin to realize what I mean when I talk about shifting 150 ft. of the stuff.”

At that time a certain County Council in the Midlands of England had just built a new dam to supply their town with water. We heard about it and wrote to them and asked them if we could knock down their old dam so that the water would run into their newly built one. They replied that this was fine because they wanted to knock it down anyway, and so the scientist and I went to work.

For many days this man worked and I flew. He modified and experimented, and

I watched and watched. Then suddenly one morning in April, on one of the first days of spring, I flew over and dropped one which worked. The man on the ground danced and waved his hands in the air. I could see him from my cockpit as I banked around after my run, and I waved back at him and shouted into the noise of the engines ; and I believe that the man on the ground threw his hat into the air, for that was a wonderful moment. After all that, I took myself back to my squadron. By now the boys had made themselves very proficient in flying at low level around the country-side, and they found that navigation in itself was no longer a problem. We therefore turned ourselves to practising a special form of attack, which we should have to make on the dam walls. Night after night, day after day, we went flying up and down lakes in Scotland, in the Midlands, and. in Wales, practising this very special form of attack. One of our hardest problems, we found, was to fly at 45 ft. above the water ; to fly at exactly 45 ft., not 44 ft. or 46 ft., but 45 ft. It is a very difficult thing for a pilot to judge his height above calm water, and many a flying-boat has crashed as a result. After two months of continuous hard training, involving at least 150 hours of flying for each person, I considered that my squadron was fit to undertake the operation. At the same time we had reconnaissance aircraft flying out over Germany watching these dams as a cat watches a mouse. On 16th May, reconnaissance aircraft reported that the water-level was just right for the attack. It was a great moment when the public address system on the station said : “ All crews of No. 617 Squadron report to the Briefing Room immediately.”

The boys came in hushed, having waited two and a half months to hear what it was that they were going to attack. There were about 175 young men in that room, rather tousled and a little scuffy and perhaps a little old-looking in spite of their youth. But they were experts, beautifully trained, and each one of them knew his job as well as any man had ever known any job which he was to do. I let the scientist tell them all about it.

Soon it was time to take off, and we rumbled out on to the flare path in one great formation, and soon all nineteen of us were en route to Germany at zero altitude. It was a wonderful sight. There was a full moon, and on either side of me stretched the two long arms of Lancasters forming a V, flying in perfect formation, each man knowing the plan, each one knowing his job. ■ We fought our way past Hamm, the well-known Hamm which used to be bombed so many times, and then as we came over the hill we saw the Mbhne Lake. And then we saw the dam itself, and in the early light of the morning it looked squat and heavy and unconquerable. A structure like a battleship was shooting up flak all along its length. It was light flak mostly, green, yellow, and red, and the colours of the tracer reflected upon the face of the water in the lake ; it reflected upon the dead calm of black water, so that it seemed to us that there was twice as much as there really was. I spoke to my squadron : “ 0.K., chaps. Come in to attack when I tell you. I’ll attack first.” The gunners saw us coming. It was not exactly an inferno. I have been through far worse flak fire than that ; but we were very low. There was something sinister and slightly unnerving about the whole operation. We skimmed along the surface of the lake, and as we went my gunner was firing into the defences, and the defences saw us coming and fired back. Their shells whistled past us, but for some reason we were not being hit. Spam said,” Left . . . little more left . . . steady . . . steady . . . steady . . . bombs gone ! ” Then it was all over. Trevor, the rear gunner, said, ” I’ll get those devils.” And he began to spray the dam with bullets until at last we were out of range. As we circled round I saw that we had not broken the dam, and so far as I could see there was not much damage, but the explosion of my mines had caused a great disturbance upon the surface of the lake and the water had become broken and

furious, as though it were being lashed by a gale. I had to wait for this to calm down and it took quite a long time.

“ Hello, M Mother. Hello, M Mother. You may attack now. Good luck.” Hoppy began his attack. Hoppy the Englishman, casual, keen now only on one thing, which was war. I saw him approach. I saw him drop his mines. I saw him shot down. Many minutes later I told No. 3 to attack. He was all right ; he got through. It was then that I saw that the dam wall had moced. It had moved back on its axis and I knew then that if we could only go on pushing, in the end it must collapse. Then one after the other, No. 4, No. 5, and No. 6 went in to attack. Now we had been over the dam for more than an hour, and all the while I was in contact with my aerodrome at home. I was in contact with my Commander in Chief and with the scientist, the man who was witnessing the last great experiment in the science of damnology. lam told that he sat in the Operations Room with his head in his hands, listening to my report as one by one I announced that aircraft had attacked, but that the wall had not broken. But I knew that the structure was shifting and then suddenly, as the last aircraft attacked and as I watched the mines drop in exactly the right place, a great column of whiteness rose up a thousand feet into the air and the dam wall collapsed. I saw it go, but I could not believe that it had happened. I heard some one shout, “ I think she’s gone I I think she’s gone ! ” And other voices picked up the call and quickly I said, Stand by until I make a recco.” Now there was no doubt about it. There was a breach 100 yards across, and the water was gushing out and rolling down into the Ruhr Valley towards the industrial centres of Germany’s Third Reich. I passed the message home to my station, and I am told that when the news came through there was great excitement in the Operations Room. lam told that the scientist leaped up and danced around the room and shouted the news. Then 1 looked again at the dam and at the water. It was a sight such as no man will ever see again. Down in the valley we saw cars speeding along the roads in front of this great wave of water which was chasing them and going faster than they could ever hope to go.