Why It Took so Many Huge Bombs to Sink This Nazi Battleship

November 5, 2019 Topic: History Region: Europe Blog Brand: The Buzz Tags: HitlerWorld War IIMilitaryTechnologyBattleship

Why It Took so Many Huge Bombs to Sink This Nazi Battleship

Meet Operation Catechism.

A particularly embarrassing episode for the Allies occurred in regard to Allied Convoy PQ-17, which departed Iceland bound for Archangel on June 27, 1942. Based on deciphered messages that the Tirpitz and other surface vessels were going to intercept the convoy, the British Admiralty ordered its escorting vessels and the convoy itself to disperse. Ironically, the Tirpitz had never sailed because the German High Command changed its mind and cancelled the raid. In the ensuing action, German aircraft and U-boats sunk 21 of the 34 merchant vessels. Shortly afterward, the Tirpitz received a general overhaul at Trondheim in which the Faetten Fjord defenses were doubled and a caisson was constructed around the stern to allow workers to replace the ship’s rudders.

The British attempted to sink her in October 1942 with two British Mk 1 Chariot torpedoes deployed by frogmen. Launched from a fishing boat in Norwegian waters, the Chariots broke free from their tow-hooks in a gale and the operation was cancelled. After the Tirpitz rudder overhaul was completed in early January 1943, she underwent sea trials to ensure the ship’s steering was in working order.

Hitler replaced Raeder with Grand Admiral Karl Dönitz on January 30, 1943. The catalyst for the move was Hitler’s lack of confidence in the Kriegsmarine’s handling of its surface ships following the Battle of the Barents Sea on December 31, 1942. The battle occurred during a raid by German cruisers and destroyers against Allied Convoy JW 51B bound for Murmansk.

During the unsuccessful raid, the British light cruiser Sheffield sank the German destroyer Friedrich Eckoldt. Hitler demoted Raeder to admiral inspector and decreed that from that point forward the Kriegsmarine would have to rely almost entirely on U-boats for convoy raiding.

However, on September 7, 1943, Hitler allowed the Kriegsmarine to send a task force composed of the Tirpitz, Scharnhorst, and nine destroyers to bombard the Free Norwegian naval base at Spitsbergen for the purpose of destroying Allied weather installations on the island. The mission was the only time the Tirpitz fired her main guns in action. She fired 52 main battery shells and 82 rounds from her secondary guns. The following day the Kriegsmarine landed a battalion of German soldiers who captured the installations and took 74 prisoners. The operation was a resounding success. Hitler could rejoice that his expensive heavies had at long last achieved a noteworthy success.

Before the month was over, the British Admiralty opted for an attack with its newly designed X-Craft midget submarines in which they would drop deadly mines underneath the Tirpitzto take advantage of its thin hull armor.

The British sent 10 of the midget submarines into the area during a five-day period beginning September 20, 1943. Eight reached the target area after two days. Three succeeded in breaching the Tirpitz’s outer water defenses. Of these, one was sunk by German gunfire and depth charges and two succeeded in depositing their mines.

One of the mines exploded abreast of gun turret Caesar, and a second blew up off her port bow, rupturing an oil tank, tearing up some armor plating, making an indentation in the hull, and buckling double-bottom bulkheads.

The crew contained the interior flooding and repaired mechanical damage; however, the Dora gun turret was torn from her rotating bearings and could not be restored right away due to a lack of heavy cranes. The battleship also lost two of her seaplanes. The German repair ship Neumark restored her to combat readiness by April 2, 1944.

The next day, 40 Barracuda dive bombers escorted by 40 fighter aircraft, attacked the Tirpitz in two waves while she was on sea maneuvers. They scored 15 direct hits at the cost of one aircraft.

The armor-piercing bombs did not penetrate the Tirpitz’s armor, but her superstructure was damaged. Casualties amounted to approximately 500 killed and wounded. The damage to the battleship consisted of the loss of a pair of 5.9-inch turrets and two more Arado Ar-196 floatplanes. The two near misses also caused flooding via holes in one side produced by shell splinters.

By June 1944 the Kriegsmarine could no longer send the Tirpitz to perform surface missions due to a lack of fighter aircraft cover; nevertheless, the Tirpitz was again deemed to be seaworthy by her own engines and enhancements were made to her antiaircraft capabilities.

The British conducted five successive Fleet Air Arm attacks on the Tirpitz during the summer of 1944 that either failed or had to be scrapped. Because of the Royal Navy’s inability to destroy the Tirpitz from the air, the mission was reassigned to the Royal Air Force Bomber Command.

By September 1944, RAF Bomber Command had opted to use the Tallboy earthquake bomb. The 12,000-pound medium-capacity bomb had a proven ability to penetrate reinforced concrete and had the potential to inflict underwater damage on a large ship at anchor. Bomber Command also planned to drop JW mines designed to rupture the vulnerable undersides of the hull, which were only protected by armor plating three-quarters of an inch thick.

Operating from a forward base at Yagodnik in the Archangel region of the Soviet Union, the first Tallboy and JW mine attack was carried out by 23 Lancasters, 17 of which carried one Tallboy each and six of which carried two JW mines each. One of the Lancasters scored a direct hit with its Tallboy on the ship’s bow. The bomb penetrated the ship, going clear through it from deck to keel before exploding at the bottom of the fjord.

Hundreds of tons of water flooded the bow, rendering the battleship unseaworthy and limiting its speed to a maximum of 10 knots. In addition, the concussive shock damaged the fire-control equipment. The Kriegsmarine High Command opted to patch up the hole as quickly as possible so that the Tirpitz could be moved from Alten Fjord south to Tromso to be farther away from the Russians, who were threatening the northeastern tip of Norway. On October 15 the Tirpitz made her final voyage, sailing 200 nautical miles to her new location.

On September 29, the British struck again with a flight of 32 Lancasters. An underwater detonation in close proximity to the battleship damaged her port rudder and shaft, which resulted in major flooding.

The Kriegsmarine then established the Tirpitz’s final defensive posture and braced for another aerial bombardment. They built a large sandbank around the ship to prevent capsizing, installed more antitorpedo netting, and reduced the crew to 1,900 officers and men.

On November 12, 1944, RAF Bomber Command executed Operation Catechism. Thirty Lancaster heavy bombers rumbled into the fjord at Tromso. The Tirpitz’s main guns roared to life, but they failed to disperse the bombers. Each of the bombers carried one 5.4-ton Tallboy bomb. The British heavy bombers scored three direct hits.

The first bomb, which landed between the gun turrets Anton and Bruno, failed to explode. A second bomb struck the vessel between its aircraft catapult and the funnel amidships. It produced enormous damage to the hull. A large hole opened up where the belted armor had been completely destroyed. The third bomb struck on the port side of gun turret Caesar.

The hit amidships led to an order to abandon ship. An internal explosion occurred 18 minutes later in the Caesar turret that blew off its roof. Debris from the explosion rained down on many of the sailors swimming to shore, producing significant casualties.

The Tirpitz capsized with her superstructure lodging itself into the sand bed. The crew launched a rescue mission to save those inside. Men used blowtorches to cut through the hull. Because of their efforts, 82 men were saved.

The Luftwaffe was roundly blamed for the sinking of the ship on the grounds that it failed to furnish sufficient air cover with fighter aircraft. Of the 1,900 crew, 1,200 were killed, wounded, or missing. The crew members who were ashore during the attack were truly fortunate.

This article originally appeared on the Warfare History Network. Originally Published February 7, 2019.
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