how many ships were sunk by u boats

Range could be estimated by an experienced operator from the signal strength. On September 21, convoy HX 72 of 42merchantmen was attacked by a pack of four U-boats, which sank eleven ships and damaged two over the course of two nights. The Germans received help from their allies. In 1939, the Kriegsmarine lacked the strength to challenge the combined British Royal Navy and French Navy (Marine Nationale) for command of the sea. The new battleship Bismarck and the cruiser Prinz Eugen put to sea to attack convoys. The defeat of the U-boat was a necessary precursor for accumulation of Allied troops and supplies to ensure Germany's defeat. Only a handful of French ships joined the, The U-boats gained direct access to the Atlantic. The Royal Navy formed anti-submarine hunting groups based on aircraft carriers to patrol the shipping lanes in the Western Approaches and hunt for German U-boats. This eventually led to the "Destroyers for Bases Agreement" (effectively a sale but portrayed as a loan for political reasons), which operated in exchange for 99-year leases on certain British bases in Newfoundland, Bermuda and the West Indies, a financially advantageous bargain for the United States but militarily beneficial for Britain, since it effectively freed up British military assets to return to Europe. But by 1942, U After negotiations with Brazilian Foreign Minister Osvaldo Aranha (on behalf of dictator Getlio Vargas), these were introduced in second half of 1941. Max Hastings states that "In 1941 alone, Ultra [breaking the German code] saved between 1.5 and two million tons of Allied ships from destruction." More U-boats were sunk, but the number operational had more than tripled. By 1945 the USN was able to wipe out a wolf-pack suspected of carrying V-weapons in the mid-Atlantic, with little difficulty. At its core was the Allied naval blockade of Germany, announced the day after the declaration of war, and Germany's subsequent counter-blockade. This had been a very successful tactic used by British submarines in the Baltic Sea and Bosporus during World WarI, but it would not work if port approaches were well-patrolled. It had been costly to the Allies. The British and French formed a series of hunting groups including threebattlecruisers, threeaircraft carriers, and 15cruisers to seek the raider and her sister Deutschland, which was operating in the North Atlantic. The development of the improved radar by the Allies began in 1940, before the United States entered the war, when Henry Tizard and A. V. Hill won permission to share British secret research with the Americans, including bringing them a cavity magnetron, which generates the needed high-frequency radio waves. The young U-boat commander had sunk nine Allied ships on his first sortie into U.S. waters. It was a foggy morning as Captain William Turner navigated the RMS Lusitania through the final and most precarious leg of its voyage from New York City to Liverpool, England. Turner, however, seemed more worried about the forebodingweather conditions overhead than any covert underwater offensive. With the exception of the Japanese invasion of the Alaskan Aleutian Islands, the Battle of the Atlantic was the only battle of the Second World War to touch North American shores. She is too fast for any submarine. In an attempt to justify the devastating attack, Germany later cited the 173 tons of war munitions the ship had also been carrying. U-100 was detected by the primitive radar on the destroyer HMSVanoc, rammed and sunk. [30] He advocated a system known as the Rudeltaktik (the so-called "wolf pack"), in which U-boats would spread out in a long line across the projected course of a convoy. [5] The vast majority of Allied warships lost in the Atlantic and close coasts were small warships averaging around 1,000 tons such as frigates, destroyer escorts, sloops, submarine chasers, or corvettes, but losses also included one battleship (Royal Oak), one battlecruiser (Hood), two aircraft carriers (Glorious and Courageous), three escort carriers (Dasher, Audacity, and Nabob), and seven cruisers (Curlew, Curacoa, Dunedin, Edinburgh, Charybdis, Trinidad, and Effingham). Norwegian Nazi puppet leader Vidkun Quisling ordered all Norwegian ships to sail to German, Italian or neutral ports. Nor were they able to focus their effort by targeting the most valuable cargoes, the eastbound traffic carrying war materiel. There was no single reason for this; what had changed was a sudden convergence of technologies, combined with an increase in Allied resources. Metox provided the U-boat commander with an advantage that had not been anticipated by the British. The machine's three rotors were chosen from a set of eight (rather than the other services' five). WebIn less than seven months, U-boat attacks would destroy 22 percent of the tanker fleet and sink 233 ships in the Atlantic Ocean and the Gulf of Mexico. A three-barrelled mortar, it projected 100lb (45kg) charges ahead or abeam; the charges' firing pistols were automatically set just prior to launch. ", O'Connor, Jerome M, "FDR's Undeclared War", WWW.Historyarticles.com, This page was last edited on 13 February 2023, at 21:47. To counter Allied air power, UbW increased the anti-aircraft armament of U-boats, and introduced specially-equipped "flak boats", which were to stay surfaced and engage in combat with attacking planes, rather than diving and evading. [85], Although the Brazilian Navy was small, it had modern minelayers suitable for coastal convoy escort and aircraft which needed only small modifications to become suitable for maritime patrol. The Lusitania attack put increased public pressure on the Wilson administration to reconsider United States involvement in World War I, leading up to an official declaration of war in 1917. When the radar operator came within 9 miles (14km) of the U-boat, he changed the range of his radar. More than 3,700 Norwegian merchant seamen died. The first confirmed kill using this technology was U-502 on July 5, 1942. Pignerolle became his headquarters.[64]. Any merchant ship that was stopped and discovered to be holding contraband cargo could be captured, boarded and escorted to a designated harbor. In the first week of May, twenty-three boats were sunk in the Baltic while attempting this journey. By May, wolf packs no longer had the advantage and that month became known as Black May in the U-boat Arm (U-Bootwaffe). The intention was to pass over the submarine, rolling depth charges from chutes at the stern at even intervals, while throwers fired further charges some 40yd (37m) to either side. The loss of Bismarck, the destruction of the network of supply ships that supported surface raiders, the repeated damage to the three ships by air raids,[e] the entry of the United States into the war, Arctic convoys, and the perceived invasion threat to Norway had persuaded Hitler and the naval staff to withdraw.[46][47][48]. An escort could then run in the direction of the signal and attack the U-boat, or at least force it to submerge (causing it to lose contact), which might prevent an attack on the convoy. While this was an embarrassment for the British, it was the end of the German surface threat in the Atlantic. This was 25% of German U-boat Arm's total operational strength. U-boats nearly always proved elusive, and the convoys, denuded of cover, were put at even greater risk. Then the depth charges had to sink to the depth at which they were set to explode. A British fleet intercepted the raiders off Iceland. It enabled the U-boat to change position with impunity. "[16], On 5 March 1941, First Lord of the Admiralty A. V. Alexander asked Parliament for "many more ships and great numbers of men" to fight "the Battle of the Atlantic", which he compared to the Battle of France, fought the previous summer. German success in sinking Courageous was surpassed a month later when Gnther Prien in U-47 penetrated the British base at Scapa Flow and sank the old battleship HMSRoyal Oak at anchor,[27] immediately becoming a hero in Germany. Their actions were restricted to lone-wolf attacks in British coastal waters and preparation to resist the expected Operation Neptune, the invasion of France. The Battle of the Atlantic pitted U-boats and other warships of the German Kriegsmarine (Navy) and aircraft of the Luftwaffe (Air Force) against the Royal Navy, Royal Canadian Navy, United States Navy, and Allied merchant shipping. [44] Bismarck nearly reached her destination, but was disabled by an airstrike from the carrier Ark Royal, and then sunk by the Home Fleet the next day. This was thought to be safe as the radio messages were encrypted using the Enigma cipher machine, which the Germans considered unbreakable. Other German surface raiders now began to make their presence felt. The escort vessels, which were too few in number and often lacking in endurance, had no answer to multiple submarines attacking on the surface at night as their ASDIC only worked well against underwater targets. "We had reached a stage when it took one or two days to decrypt the British radio messages. There were so many U-boats on patrol in the North Atlantic, it was difficult for convoys to evade detection, resulting in a succession of vicious battles. A drop in Allied shipping losses from 600,000 to 200,000tons per month was attributed to this device.[69]. Although Allied warships failed to sink U-boats in large numbers, most convoys evaded attack completely. In October, the slow convoy SC 7, with an escort of two sloops and two corvettes, was overwhelmed, losing 59% of its ships. With the battle won by the Allies, supplies poured into Britain and North Africa for the eventual liberation of Europe. The situation in Royal Air Force Coastal Command was even more dire: patrol aircraft lacked the range to cover the North Atlantic and could typically only machine-gun the spot where they saw a submarine dive. Cookie Settings, Dead Wake: The Last Crossing of the Lusitania, contraband cargo could be captured, boarded and escorted, fair notice to its rivals by declaring unrestricted submarine warfare, sunk 39 ships and lost only three U-boats in the process, 5,000 ships and resulting in the loss of 15,000 lives. By the time they withdrew on February 6, they had sunk 156,939tonnes of shipping without loss. These sets were common items of equipment by the spring of 1943. Although the narrow fjords gave U-boats little room for manoeuvre, the concentration of British warships, troopships and supply ships provided countless opportunities for the U-boats to attack. Although 13merchant ships were lost, six U-boats were sunk by the escorts or Allied aircraft. The British codebreakers needed to know the wiring of the special naval Enigma rotors, and the destruction of U-33 by HMSGleaner (J83) in February 1940 provided this information. In May, the Germans mounted the most ambitious raid of all: Operation Rheinbung. This state persisted for ten months. With so many German raiders at large in the Atlantic, the British were forced to provide battleship escorts to as many convoys as possible. The European naval powerbegan operating U-boats in 1914, as an alternative to standard warships, which carried the not-insignificant downside of being visible to enemyvessels. [86] During its three years of war, mainly in Caribbean and South Atlantic, alone and in conjunction with the US, Brazil escorted 3,167 ships in 614 convoys, totalling 16,500,000 tons, with losses of 0.1%. [13] The Germans were joined by submarines of the Italian Regia Marina (Royal Navy) after Germany's Axis ally Italy entered the war on June 10, 1940. With the outbreak of war, the British and French immediately began a blockade of Germany, although this had little immediate effect on German industry. The Flower-class corvette escorts could detect and defend, but they were not fast enough to attack effectively. From the bestselling author and master of narrative nonfiction comes the enthralling story of the sinking of the Lusitania. This new key could not be read by codebreakers; the Allies no longer knew where the U-boat patrol lines were. Unrestricted submarine warfare had been outlawed by the London Naval Treaty; anti-submarine warfare was seen as 'defensive' rather than dashing; many naval officers believed anti-submarine work was drudgery similar to mine sweeping; and ASDIC was believed to have rendered submarines impotent. The British, however, developed an oscilloscope-based indicator which instantly fixed the direction and its reciprocal the moment a radio operator touched his Morse key. The early wartime Royal Navy procedure was to sweep the ASDIC in an arc from one side of the escort's course to the other, stopping the transducer every few degrees to send out a signal. U-boats played a pivotal role in helping Germany react to the economic offensive that Britain had established with its blockade, by responding in kind and cutting off merchant business and trade. The campaign peaked from mid-1940 through to the end of 1943. The 700,000 ton target was achieved in only one month, November 1942, while after May 1943 average sinkings dropped to less than one tenth of that figure. The battle was the first clear Allied convoy victory.[61]. The following day the U-boat was beached in an Icelandic cove. In April 1941 President Roosevelt extended the Pan-American Security Zone east almost as far as Iceland. After this initial burst of activity, the Atlantic campaign quieted down. No fewer than 2,603 merchant ships had been sunk, totalling over 13. Nevertheless, the U-boats continued to take a heavy toll on the Atlantic convoys: 59 ships were sunk in September 1940 and 63 in October, which, combined with the 56 vessels lost in August, meant that in three months 700,000 tons of supplies had disappeared beneath the waves. By spring of the next year, Germany had roughly 35 functioning U-boats, many of which utilized torpedoes and had been highly effective in targeting ships passing through their vicinity. As an island country, the United Kingdom was highly dependent on imported goods. In May, King (by this time both Cominch and CNO) finally scraped together enough ships to institute a convoy system. Before the war, Norway's Merchant Navy was the fourth largest in the world and its ships were the most modern. In 1943 and 1944 the Allies transported some 3 million American and Allied servicemen across the Atlantic without significant loss. I was even more anxious about this battle than I had been about the glorious air fight called the 'Battle of Britain'. By 1941 American public opinion had begun to swing against Germany, but the war was still essentially Great Britain and the Empire against Germany. Hedgehog was a multiple spigot mortar, which fired contact-fused bombs ahead of the firing ship while the target was still within the ASDIC beam. [59] Although the Allies could protect their convoys in late 1941, they were not sinking many U-boats. Squadron Leader J. Thompson sighted the U-boat on the surface, immediately dived at his target, and released four depth charges as the submarine crash dived. With the exception of men like Dnitz, most naval officers on both sides regarded surface warships as the ultimate commerce destroyers. The Royal Navy's main anti-submarine weapon before the war was the inshore patrol craft, which was fitted with hydrophones and armed with a small gun and depth charges. These aircraft first made contact with enemy submarines using air-to-surface-vessel (ASV) radar. By August 1942, U-boats were being fitted with radar detectors to enable them to avoid sudden ambushes by radar-equipped aircraft or ships. In April, the Admiralty took over operational control of Coastal Command aircraft. The hunting group strategy proved a disaster within days. The US did not have enough ships to cover all the gaps; the U-boats continued to operate freely during the Battle of the Caribbean and throughout the Gulf of Mexico (where they effectively closed several US ports) until July, when the British-loaned escorts began arriving. Not a single British warship was sunk by a U-boat in more than 20attacks. The success of pack tactics against these convoys encouraged Admiral Dnitz to adopt the wolf pack as his primary tactic. As a result, the Axis needed to sink 700,000GRT per month; as the massive expansion of the US shipbuilding industry took effect this target increased still further. Among these upgrades were improved anti-aircraft defences, radar detectors, better torpedoes, decoys, and Schnorchel (snorkels), which allowed U-boats to run underwater off their diesel engines. [107] The Empire of Japan also adhered to the idea of a fleet submarine, following the doctrine of Alfred Thayer Mahan, and never used their submarines either for close blockade or convoy interdiction. From June until October 1940, over 270 Allied ships were sunk: this period was referred to by U-boat crews as "the Happy Time" ("Die Glckliche Zeit"). Therefore, a few large convoys with apparently few escorts were safer than many small convoys with a higher ratio of escorts to merchantmen. Of the U-boats, 519 were sunk by British, Canadian, or other UK-based forces, 175 were destroyed by American forces, 15 were destroyed by the Soviets, and 73 were scuttled by their crews before the end of the war for various reasons. Early on, many German officials began to believe U-boats would offer a swift and decisive victory to the war. There are fears more than 100 people, including children, have died after their boat sank off southern Italy. Developed by RAF officer H. Leigh, it was a powerful and controllable searchlight mounted primarily to Wellington bombers and B-24 Liberators. Larger numbers of escorts became available, both as a result of American building programmes and the release of escorts committed to the North African landings during November and December 1942. After fourmonths, BdU again called off the offensive; eightships of 56,000tons and sixwarships had been sunk for the loss of 39U-boats, a catastrophic loss ratio. Between April and July 1940, the Royal Navy lost 24destroyers, the Royal Canadian Navy one. The Type VIIC began reaching the Atlantic in large numbers in 1941; by the end of 1945, 568 had been commissioned. Then on October 30, crewmen from HMSPetard salvaged Enigma material from German submarineU-559 as she foundered off Port Said. Others, including Blair[98] and Alan Levine, disagree; Levine states this is "a misperception", and that "it is doubtful they ever came close" to achieving this. Most were destroyed in Operation Deadlight after the war. In 1940, the French Navy was the fourth largest in the world. These started to be installed on anti-submarine ships from late 1942. A series of battles resulted in fewer victories and more losses for UbW. King has been criticised for this decision, but his defenders argue the United States destroyer fleet was limited (partly because of the sale of 50 old destroyers to Britain earlier in the war), and King claimed it was far more important that destroyers protect Allied troop transports than merchant shipping. When news of the sinking reached the US, few shipping companies felt truly safe anywhere. Henceforth the U.S. would either have to recall its ships from the ocean or enforce its right to the free use of the seas."[50]. The director in charge of torpedo development continued to claim it was the crews' fault. However, the standard approach of anti-submarine warships was immediately to "run-down" the bearing of a detected signal, hoping to spot the U-boat on the surface and make an immediate attack. Subsequently, the common practice of surfacing at night to recharge batteries and refresh air was mostly abandoned as it was safer to perform these tasks during daylight hours when enemy planes could be spotted. Germany returned to the offensive in the North Atlantic in September 1943 with initial success, with an attack on convoys ONS 18 and ON 202. (As mentioned previously, not a single troop transport was lost.) The Britishbegan to take U-boats more seriously after a major stealth attack decimated three of its large cruisers, the HMS Aboukir, Hogue and Cressy in September 1914. When the year ended 9 of them had been lost. (This may be the ultimate example of the Allied practise of evasive routing.) [citation needed], Despite their efforts, the Axis powers were unable to prevent the build-up of Allied invasion forces for the liberation of Europe. [68] U-boat commanders who survived such attacks reported a particular fear of this weapon system since aircraft could not be seen at night, and the noise of an approaching aircraft was inaudible above the din of the sub's engines. Since a submarine's bridge was very close to the water, their range of visual detection was quite limited. [67], Detection by radar-equipped aircraft could suppress U-boat activity over a wide area, but an aircraft attack could only be successful with good visibility. Ten ships were sunk, but another U-boat was lost. [68], The Leigh Light enabled the British to attack enemy subs on the surface at night, forcing German and Italian commanders to remain underwater especially when coming into port at sub bases in the Bay of Biscay. It was to be many months before these ships contributed to the campaign. [75] The next two months saw a complete reversal of fortunes. 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