05/05/2024
German underwater WWII tanks
Underwater Panzer tanks on Eastern Front
"An interesting new secret weapon was employed here for the first time—underwater tanks AKA as diving tanks. They were to cross the river under water, just like submarines. Then, on the far bank, they were to go into action as ordinary tanks, smashing enemy positions along the river and intercepting any counter-attacks. In fact, the plan was over a year old and had been intended for Operation Sea Lion, the invasion of England. The idea was that they would be unloaded well off the south coast of England, in about 25 feet of water, to advance over the sea-floor to the flat beaches. There they were to have emerged from the waves, like Neptune, to have fought down the British coastal defences on both sides of Hastings, to have formed bridgeheads for the first German landing craft, and eventually to have advanced inland, causing havoc and panic in the coastal hinterland.
The idea was immediately put into effect. In July 1940 four diving-tank sections were formed from eight experienced Panzer regiments, and posted to Putlos on the German Baltic coast for special training. It was a strange course for the tank crews. In their Mark III and IV tanks they virtually turned into U-boat men. The operational task required manoeuvrability in water of twenty-five to thirty feet. That meant that the tanks had to withstand a water pressure of about two atmospheres and had to be appropriately sealed. This was achieved by a special adhesive. Sealing the joint between turret and tank body was done very simply by means of an extended bicycle inner tube which could be inflated by the gun-loader inside the tank. The gun itself was fitted with a rubber muzzle cap which could be blasted off from the turret within a second.
A special problem, however, was the supply of fresh air to the engine and the crew. Here the principle of the later U-boat snorkel was anticipated. A special hose about fifty feet long was fitted by a special suction device to a floating buoy, which, at the same time, carried an aerial. The tanks were steered with the aid of a gyro-compass. Towards the end of July 1940 the four detachments practised in strictest secrecy at Hörnum on the Island of Sylt. An ancient ferry of the Rügen service would take them well out to sea; there they would slither down a hinged ramp to the sea-floor, and make their own way back to the coast. The unevenness of the seabed did not seem to worry the monsters. The experiments were highly successful. But then, in mid-October 1940, Operation Sea Lion was called off for good. The dream of the U-boat tanks had ended. Of the special detachments three were united into a plain tank regiment, 18th Panzer Regiment, while the remaining detachment was assigned to 6th Panzer Regiment, 3rd Panzer Division.
In the spring of 1941, when the High Command of the Army was discussing the crossing of the Bug north of Brest, in connection with the planning of Operation Barbarossa, somebody on the General Staff remembered the diving tanks. "Surely we had those things . . ." Inquiries were made. Questions were asked at 18th Panzer Regiment. "Oh, yes, we still have those old diving tanks." An order came for diving basins to be built near Prague. 18th Panzer Regiment tested the diving capacity of the old tanks. Since they were no longer required to move under the sea, but merely to cross a river, the fifty-foot-long rubber snorkel was replaced by a ten-foot steel pipe. The exhaust pipes were fitted with one-way valves. Within a short time the U-boat tanks were again in perfect condition. On 22nd June 1941 they passed their ordeal by fire.
In the sector of 18th Panzer Division fifty batteries of all calibres opened fire at 0315 in order to clear the way to the other bank for the diving tanks. General Nehring, the divisional commander, has since described this as "a magnificent spectacle, but rather pointless since the Russians had been clever enough to withdraw their troops from the border area, leaving behind only weak frontier detachments, which subsequently fought very bravely."
At 0445 hours Sergeant Wierschin advanced into the Bug with diving tank No. 1. The infantrymen watched him in amazement. The water closed over the tank. "Playing at U-boats!" Only the slim steel tube which supplied fresh air to the crews and engine showed above the surface, indicating Wierschin's progress under water. There were also the exhaust bubbles, but these were quickly obliterated by the current.
Tank after tank—the whole of 1st Battalion, 18th Panzer Regiment, under the battalion commander, Manfred Graf Strachwitz—dived into the river. And now the first ones were crawling up the far bank like mysterious amphibians. A soft plop and the rubber caps were blown off the gun muzzles. The gun-loaders let the air out of the bicycle inner tubes round the turrets. Turret hatches were flung open and the skippers wriggled out. An arm thrust into the air three times: the signal "Tanks forward."
Eighty tanks had crossed the frontier river under water. Eighty tanks were moving into action.
Their presence was more than welcome in the bridgehead. Enemy armoured scout-cars were approaching. At once came the firing orders for the leading tanks: "Turret—one o'clock —armour-piercing—800 yards—group of armoured scout-cars —fire at will."
The monsters fired. Several armoured scout-cars were burning. The rest retreated hurriedly. The armoured spearheads of Army Group Centre moved on in the direction of Minsk and Smolensk."
-- from Moves East by Paul Carell
