Navy sailors salvage Nazi German U-boat submarine U-505
US Navy sailors work to save German submarine U-505 shortly after it was abandoned by its crew, June 4, 1944.US Navy
  • The Allied armies were about to cross the English Channel.

  • The US Navy was about to land a blow on the Nazis.

  • It was an intelligence coup to capture U-504.

In early June 1944, more than 100,000 Allied soldiers and thousands of ships and aircraft massed on the English coast, ready for the invasion of Normandy.

The six ships of US Navy Task Group 22.3 were on a mundane patrol hundreds of miles to the south.

The task force left for Casablanca after a few weeks at sea. One of the most impressive naval feats of the war was the capture of the German U-boat U-505 completely intact, which included its valuable Enigma machines and the code books needed to use them.

U-505

Navy destroyer USS Chatelain closes on U-boat submarine U-505
USS Chatelain closes in on the damaged U-505, June 4, 1944.US Navy

U-505 was a type IXC U-boat with a crew of 60 and was 250 feet long. The deck gun and two anti-aircraft guns were removed by 1944.

U-504 became known for being unlucky. Many of its patrols were cut short because of mechanical issues. The first commanding officer had an appendix removed and the second had a mental breakdown and killed himself.

The accidental sinking of a Colombian diplomat's schooner, which contributed to that country declaring war on Germany in November 1943, was one of the eight ships that U-504 sank.

Navy carrier USS Guadalcanal tows captured U-boat submarine U-505
USS Guadalcanal tows U-505 on June 4, 1944.US Navy

In the summer of 1944, U-504 was commanded by the Oberleutnant von See Harald Lange and was operating off the West African coast.

The German U-boat fleet had a happy time. The Allies used intercept messages to determine the general area and timing of U-boat operations.

The Allies didn't know where German subs would be because they hadn't gotten their hands on a newer version of the cipher used by the subs.

The capture

Members of the salvage party from USS Guadalcanal use a small handy-billy pump aboard the partially scuttled U-505, June 4, 1944.US Navy

Task Group 22.3 left Norfolk on May 15. It was commanded by Capt. Daniel Gallery, an anti-submarine-warfare pioneer, with the Casablanca-class escort carrier and five destroyers.

Gallery sunk U-515 and U-68 within 12 hours of each other, but he knew that capturing a German sub was more important. Task Group 22.3 was told to train to capture a U-boat instead of sinking it.

After weeks of searching for the sub off of West Africa, the task group ran out of fuel and headed north for Casablanca.

U-504 was running low on fuel and had set a course for France.

US Navy salvage parties work on U-505 with a TBM Avenger overhead and USS Chatelain in the background, June 4, 1944.US Navy

The destroyers Chatelain, Jenks, and Pope moved in after the two F4F Wildcat fighter planes launched from Guadalcanal.

U-504 was only about 60 feet deep and was discovered by the two parties at the same time. The destroyers fired anti-submarine mortars and dropped over 60 depth charges to mark the course of U-505.

The crew of U-504 believed the hull was cracked and that they would soon sink. They were told to abandon the ship less than 800 yards from the town.

He put his plan into action. All five destroyer escort took position around the sub as it surfaced and sprayed it with machine-gun fire, which wounded Lange and killed his chief officer.

A herculean effort

A boarding party from USS Pillsbury secures a tow line to the bow of U-505, June 4, 1944.US Navy

The Germans jumped into the water after the destroyers stopped firing. In their haste to leave the ship, they didn't set the scuttling charges correctly.

A group of men from Pillsbury boarded U-504. The boarding party grabbed as much codebooks, documents, and maps as they could after the F4Fcats fired into the water.

The US sailors went to great lengths to save U-504. The sub sailed in a straight line after its rudder and engine were damaged. When the engine was disabled, they closed the valves and turned it on again.

Pillsbury gave up trying to tow the sub because U-504 kept running into it and tearing a hole in the destroyer's hull. The bow and conning tower were the only things above the surface at one point.

US Navy fleet ocean tug USS Abnaki tows U-505 in the Atlantic, June 4, 1944.US Navy

A member of the Germans agreed to help the Americans. Felix showed them how the pumps work.

Guadalcanal took the submarine under tow after the engine was disconnected. The towing made the propellers spin, which charged the sub's battery and allowed the pumps to work.

A large American flag was flying over the German ensign. It was the first time in 200 years that US Navy personnel boarded and captured an enemy ship.

The chief of US naval operations, Adm. Ernest J. King, was initially angry but soon realized the value of the sub.

U-505 on display at the Chicago Museum of Science and Industry.J.B. Spector/Museum of Science and Industry

To keep the news of U-505's capture from spreading, the sub was towed 1,700 miles to Port Royal Bay in the British Virgin Islands. The US colors were used to paint the sub.

The German crew, all but one of whom survived, was held in isolation at a camp in Louisiana, which was a violation of the convention on treatment of POWs.

Intelligence was given by U-504. Ten sacks full of codebooks, documents, and maps weighing over 900 pounds were recovered.

The war in Europe was over when the sub was captured. War bond sales were encouraged by using it as a prop. After the war, U-505 was to be used for torpedo practice, but it was donated to the Museum of Science and Industry in Chicago.

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