How Hitler terrorized the seas with U-boats during World War II

German-Hitler-Nazi-U-boats-parade-review

Photo: German Federal Archives

“The only thing that ever really frightened me during the war was the U-boat peril,” British Prime Minister Winston Churchill reportedly said while reflecting on the second world war.

By the end of the war, Hitler’s Kriegsmarine, the navy of Nazi Germany, had built 1,162 U-boats, which is short for the German word “Unterseeboot,” or undersea boat.

In the fall 2015 issue of Weapons of WWII magazine, Marc DeSantis explains how the U-boats were used during World War II.

At the beginning of the war, the commander of the German U-boat fleet, Karl Dönitz, said that if he had 300 U-boats, “he could strangle Britain and win the war.”

Karl-dnitz-german-u-boat-admiral

Photo: Wikimedia Commons

The Kriegsmarine began the war with just 56 U-boats, but over the course of the war they would build 691 type VII U-boats alone. Here’s a photo of a U-35 boat during training exercises in 1936.

Kriegsmarine-German-Navy-u-boat-training

Photo: German Federal Archives

The U-boat was not a true submarine in today’s sense of the word. It was more of a submersible craft. The diesel engines required air, so while underwater, the craft was powered by 100 tons of lead-acid batteries, meaning it had to surface every few hours when air and battery power were exhausted.

The battery power made the U-boats exceptionally slow underwater, clocking in at 8 knots (9.2 mph), compared to 17.2 knots (19.8 mph) above water on the VII-B models.

German-submarine-U-14

Photo: Library of Congress

The boats were manned by up to 44 men …

german-sub-grew-world-war-II

Photo: German Federal Archives

… who shared extremely crammed quarters.

submarine-engines

Photo: Youtube

The U-boat featured a fearsome 88-millimeter cannon on the deck, as well as a 20-millimeter antiaircraft gun. Here’s the cannon in action:

U-boats were also equipped with torpedoes for underwater attacks. Here’s a photo of a German G7 torpedo, the standard torpedo for all German U-boats and surface torpedo-bearing vessels of the war.

Photo: German Federal Archives

Photo: German Federal Archives

However, many early torpedoes fired by U-boats did not function properly, either exploding prematurely or not at all.

Photo: Wikimedia Commons/German Federal Archives

Photo: Wikimedia Commons/German Federal Archives

By 1943, Allied forces began fiercely hunting U-boats at sea. Here’s an Allied pilot bombing a U-boat.

Toward the end of the war, the U-boats were death traps. Of 40,900 men who manned U-boats, some 28,000, or 70%, were killed. Here’s a photo of US troops boarding a captured German U-boat.

american-sailors-board-german-u-boat-submarine

Photo: Wikimedia Commons

German U-boats sank more than 2,600 Allied ships carrying supplies during World War II.

Photo: Wikimedia Commons

Photo: Wikimedia Commons

More from Business Insider:

This article originally appeared at Business Insider Defense. Copyright 2015. Follow BI Defense on Twitter.

TOP ARTICLES
These are the military traditions for deployed troops celebrating Thanksgiving

While you're deployed, weekends aren't really a thing — neither are most holidays. Thanksgiving, however, is a moment when the military slows down.

Forget multitasking, this Navy squadron has only one mission — rescue people

The Navy has an entire squadron for search and rescue, and it is the only squadron in the Navy that has an advance life-support helicopter platform.

How the Coast Guard intercepts half a million pounds of cocaine

For the last couple decades, the Coast Guard has pushed out further, taking more aggressive stabs at the flow of drugs that make their way into the U.S.

More remains of Special Forces soldier found in Niger

The Department of Defense announced that military investigators found additional remains that they have positively ID'd as Sgt. La David T. Johnson.

'Butcher of of Bosnia' sentenced to life in prison for genocide

"The Butcher of Bosnia" was handed a life sentence on November 22nd, 2017, for war crimes and the slaughter of 8,000 men and young children.

New engravings on the USMC War Memorial honor Iraq and Afghanistan Marines

On Nov. 22, the U.S. Marine Corps War Memorial was updated to include Afghanistan and Iraq in the list of campaigns that runs along the memorial's base.

ISIS may focus on a virtual caliphate after losing real-world war

As the Islamic State loses the in real life war they've waged against the world, they've moved their game online- waging war in the virtual world.

Everything you need to know about Zimbabwe's ousted dictator

The dictator of Zimbabwe announced his resignation on Nov. 21, 2017 after the county's army took of the capital and family, forcing the resignation.

Watch this Marine get pinned by his 3-year-old son

Watch this adorable little boy steal into the hearts of all the Marines and civilians present as he promotes his dad and pins on his promoted rank.

Watch a North Korean defector dodging bullets to cross the DMZ

A North Korean attempting to defect to the South, who was found to be full of parasites, was shot by his fellow soldiers. We Are the Mighty has the video.