Submarines became key players during World War II in both the Pacific and Atlantic. The World War II submarine was a submarine in name over. Even the best of them like the German Type-IX and the American Gato-class shi[s were more acurately described as torpedo boats that were capable of submerging for short periods. World War II submarines spent most of their time on the surface. This was because the electric engines used underwater ran on bateries with limited capacities. And they could only be recharged on the surrface. In addition, the World War II submarines ran much slower under water than they could on the surface. Several navies, including the Germans and Japanese had major submarine forces. The Allies dominated the Altlantic surgace forces, but the submarines were adiffent matter. The only successful submarine campaign, however, was fought by the U.S. Navy in the Pacific. With the outbreal of World War II in Europe, the Germany Kreigsmarine again unable to match the Royal Navy, again launched a commerce war. The Royal Navy had underestimated the submarine which they concluded had been made obsolete by ASDAC (SONAR). This proved not to be the case, at least until modern more effective SONAR was developed. Admiral Dönitz, head of the German U-boat fleet, developed innovative Wolf Pack tactics that threatened to accomplish what the U-boats had failed to do in World War I. Prime Miniter Churchill wrote after the War that it was the U-boats that caused him the greatest anxiety during the war. And Dönitz's primary weapon was the Type-IX. Fortunately for the British, OKM restricted the number of U-boats built in general as well as the number of Type IX's built until the War was well underway. Britain was not the only industrialized island nation that was vulnerable to a sunmarine-based commerce war. Japan was even more dependant on imported food and raw materials than Britain. This was a vulnerability the Japanese for reasons only they can explain did not attach much importance to when they launched the Pacific War. It would be the United States that would conduct the only successful submarine campaign of the war. The primary American submarine was the Gato-class ship, twice as large as the faned German Type-IX. This reflected both the greater American industrial capacity and the needs of a campaign waged in the vast Pacific. The Pacific Fleet's submarine chief, Adm. Charles Abner Lockwood, studied Dönitz's tactics in the Atlantic. He decided on smaller wolfpacks, in part because the Japanese Marus sailed without convoys or in small convoys.
It was not until years after the War that historians learned how important the American codebreaking effort was to the American success. Had the Japanese not surrendered (August 1945), they faced mass starvation in the winter (1945-46). Unlike the Americans, the Japanese did not use their sizeable sumarine force in a commerce war. The American submarine force of about 270 ships was an almost negligibe part of the vast naval force America woulkd deploy in World War II, at about 2 percent. They account, howver, for about 50 percent of Japanese shiping losses.
Submarines became key players during World War II in both the Atlantic and Pacific. Hitler had not placed much importance on the Kriegsmarine and go the xtent he did he focused on surace ships, especially big gun battleships. The riegsmarine primry focus was a instrument to boh cut Britain's lifelines and second to make it impossible for the United States to projet power. Erly in the War, however, it became obvious that the Kriegsmarine could not accomplish this with surface ships. And Admiral Dönitz's small U-boat fleet was reporting enormous success. Prime Miniter Churchill wrote after the War that it was the U-boats that caused him the greatest anxiety during the war. Hitler thus approved a major U-boat building program. This was at the time that he was also prepring Barbarossa. The steel and other resources devoted to U-boats affected the production of otherars including tanks and artillery. The resulting battle of the Atlantic proved to be one of the citical campigns of the War. Unlike the Germans,the Japanese began the War with a substantial submarine force. It would, howver, be the U.S. Navy's Submarine Srvice that would play a key role in the Pacific War. Britain was not the only industrialized island nation that was vulnerable to a sunmarine-based commerce war. Japan was even more dependant on imported food and raw materials than Britain. This was a vulnerability the Japanese for reasons only they can explain did not attach much importance to when they launched the Pacific War. The Japanese had a growing indusrial economy, but only limited natural resources needed to supply it. They went to war to seize the Southern Resource Zone (SRZ) of SoutheastAsia. They succeeded in this effort, but the Japnese marus plying he long sea lanes between the SRZ and ine industry of the Home Islands was vulberable. It would be the United States that would conduct the only successful submarine campaign of the war.
The World War II submarine was a submarine in name over. Even the best of them like the German Type-IX and the American Gato-class shi[s were more acurately described as torpedo boats that were capable of submerging for short periods. World War II submarines spent most of their time on the surface. This was because the electric engines used underwater ran on bateries with limited capacities. And they could only be recharged on the surrface. In addition, the World War II submarines ran much slower under water than they could on the surface. Several navies, including the Germans and Japanese had major submarine forces. The Allies dominated the Altlantic surgace forces, but the submarines were adiffent matter. The only successful submarine campaign, however, was fought by the U.S. Navy in the Pacific. With the outbreal of World War II in Europe, the Germany Kreigsmarine again was unable to match the Royal Navy, again launched a commerce war.
All of the major World War II belligerants had submarine fleets. Only the United States and German submarines, however, played a major role in the War. Japan had a very substantial submaroine force which could have like the U.S. Navy played an important role in the Pacific War. The vast reaches of the Pacific created major logistical difficulties, thus creating opportunities for submarine operations againstvulnerable cargo vessels. . The Imperial Navy, however declined to focus on American cargo vessels. The commandrs and vessel captains, however, set their signs on more prestious, but more difficult to attack naval vessels. The Japanese also used their submarines in a vain effort to supply cut off and starving Pacific island garrisons. While the German U-boats have received the greatest historical coverage, it would only be the U.S. Navy submarine force that would comnduct a successful campaign.
World War II naval histories focus very intensely on the German U-boat force and the Allied efforts to defeat it. Ironically German admirals before the War wanted a big-gun surface fleet. Hitler with his penchant for military giganitism actually promised them just such as fleet, but then advanced the time table for war. Thus the Kreigsmarine unlike World war I began the War with only a small surface fleet. As a result of World War I, most German and British admirals did not believe the U-boat was a formidable weapon and this were still big-gun battleship enthusiasts. Admiral Döenitz thus had only a small U-boat force when Hitler launched the War, but they were very well trained. The U-boat proved again to be Germany's primary naval threat. Once this became apparent, Hitler ordered a massive U-boat construction program. Churchill after the War wrote that the u-boat campaign in the Battle of the Atlantic was the one threat that really worried him. The fall of France provided the Germans Atlantic ports that they were denied in World War I and which greatly greatly incrased the effectiveness and striking power of the growing U-boat fleet. The effectiveness of the U-boats can be seen when President Roosevelt ordered took the extrodinary action of ordering the U.S. Navy into an undeclared naval war in the Atlantic months before the United State actually entered the war. Even so, Hitler did every thing he could to avoid incidents with the Americans in the Atlantic. He was intent on keeping America out of the war until he completed the conquest of the Soviet Union. His anger at having to do this was so intense that it is probanly the primary reason that after the Japanese attack on Pearl Harbor that he so readily declared war on the United States. This freed the U-boats to launch a highly successful attack on shipping along the Amerucan Eastern Coast. The Battle of the Atlantic would be the decisive campaign waged by the Western Allies. Ironically while the German U-boat campaign is one of the great legends of World War II, endlssly chronicled in film and literature, it was the Americans in the Pacific who waged the only successful submarine campaign--a stark example of what the Germans might have achieved. All of the other Allied campaigns in Europe were contingent on defeating the U-boats in the North Atlantic.
Italy
The Japanese Navy got its first submarines from the United States, buying them from the Electric Boat Company in the early 20th century. More sophisticated submarines were obtained as part of the World War I peace settlement. The Allies gave the Japanese a number of German U-boats. After the War, the Japanese Navy began to focus on the American Navy as its most likely future opponent. The Japanese began building an advanced submarine, the I-class submarines. This submarine reflected the empire that Japan began to conceive in Southeast Asia and the Pacific. The I-boats were very large submarines, reflecting the vast distances involved in Pacific operations. The I-class were 350 ft long and had ranges of 20,000 miles, more than twice that of 7,000-8,000 mile range of the German U-boats. The Japanese had smaller subs for coastal patrol, but the backbone of the fleet was the I-class boats. Surprisingly the substantial Japanese submarine fleet with the unique capabilities of its boats, had little impact on the Pacific campaign. Unlike the Americans, the Japanese began the War with the effective Type 93 Long-Lance Torpedo. The Japanese Navy never used their submarines to interdict American supply vessels. Rather they were used to target fighting ships with only limited success because of their tactical deployment. The Japanese used theor submarines as scouts and to targer warships. As the American offensive moved toward the Home Islands, the Japanese used their submarines to supply bypassed island garisons, some of which were near starvation. They were also used to supply bypassed islasnd bases where garrisons were close to starvation. They also managed to get some secret German military technology to Japan late in the war (1944). The Japanese developed especially large sunmarines that could carry a few planes. They were planning an attack on the Panama Canal until the subarines were redeployed to defend Okinawa (1945).
Soviet Union
The Soviet Union inherited the Tsarist Navy. After the Russian Civil War and the the development of the Soviet military, the emphasis was given to the Red Army and land warfare and to alesser extenbt the Red Air Force. The Red Navy was a poor step child. There was virtually no attention to submarines until the beginning of the 1930s. The Red Navy began a submarine building program (early-1930s). There were two majpr classes. The M-class was designed for the Pacific meaning seeper and longer missions. The Shchuka Class was designed for more shallow European waters ans shorter missons (the Baltic Sea, Black Sea, and other coastal waters). They Soviet subs were smaller than the German subs, only anout two-third as large. The Soviets had, however far more subs than the Germans at the time the War broke out, about 200, more tha three time the sie of the German submarine force. Muh of this force, however, was based in the Pacific and thus of no use when the Germans sruck (June 1941). The Baltic as Barbarossa unfoldered became a German lake. German ships and aircraft inflicted heavy losses. The Soviets lost almost all their Baltic ports And the Gerans and Finns contructed anti-submarine barriers majing it difficult for the Red Navy subs to opeate in the Baltic. The Soviets almost lost almost all their Black Sea ports. The Soviets introduced mass roduction in their war industries far in advance of the Germans and thi included submarine production. The Germans were working on this with the highly advanced Type 21, but the Allied Strategic Bombing campaign meant that there were no large assembly plants and there were difficulties in getting the compnents to fit together. It was a factor in deplaying the progran abd the Type 21s never entered service. The Soviet mss production effort produced a lot of subs, but their production efforts d astandards were substandard leading to many losses. But with te advance of the Red Army in both the Baltic and Black Sea areas, the Soviet subs began to take a toll on Gema shipping. Soviet sub caused the largest loss of life in mritime history, sinking the the German liner Wilhelm Gustloff caring refugees and wounded men cut off by the advancing Red Army. Some 10,000 people were killed. Another Soviet sub sank the Riga, killing anither 5,000 refugees and wounded men trying to ecape the the Red Army as part of Operation Hannibal.
Not only were the Soviet sunspooly built, but the Soviet designers gave virtually no consideration torew comforts. The bunks were welded directly to the diesel engines. Even the Germans esperate for space didn’t do this. The result was that loss of hearing and even some limbs.
American submariners often do not get the appreciation due. As Admiral Nimitz explained, it was the submarine force that held the line while America rebuilt its fleet. American submarines, however, were hampered by poor strategic and tactical concepts and ineffective torpedoes in 1942. The American submarines by 1943, however, began to significantly affect the delivery of raw materials to Japan. The American submarines targeted the Japanese merchant marine (maru) fleet. While the big fleet carriers got the headlines. The American submarines sunk over 50 percent of all Jpanee vessels destroyed during the War. The Japanese merchant marine was almost completely destroyed, cutting the country's war industries off from supplies and bringing the country close to starvation by 1945. The American submarines did to Japan what the German u-boats tried to do to Britain. Surprisingly the Japanese submarine fleet had little impact on the Pacific campaign. Unlike the Americans, the Japanese began the War with the effective Type 93 Long-Lance Torpedo. The Japanese Navy never used their submarines to interdict American supply vessels. Rather they were used to target fighting ships with only limited success because of their tactical deployment. The Japanese used theor submarines as scouts and to targer warships. As the American offensive moved toward the Home Islands, the Japanese used their submarines to supply bypassed island garisons, some of which were near starvation. They were also used to supply bypassed islasnd bases where garrisons were close to starvation. They also managed to get some secret German military technology to Japan late in the war (1944).
Electronics
The Royal Navy had underestimated the submarine which they concluded had been made obsolete by ASDAC (SONAR). This proved not to be the case, at least until modern more effective SONAR was developed.
Tactics
Admiral Dönitz, head of the German U-boat fleet, developed innovative Wolf Pack tactics that threatened to accomplish what the U-boats had failed to do in World War I. The Pacific Fleet's submarine chief, Adm. Charles Abner Lockwood, studied Dönitz's tactics in the Atlantic. He decided on smaller wolfpacks, in part because the Japanese Marus sailed without convoys or in small convoys. It was not until years after the War that historians learned how important the American codebreaking effort was to the American success.
Code Breaking
Abwehr code breakers cracked the British Naval codes, providing Admral Dönitz a great deal of valuable information. Ultra played a major role in the Battle for the Atlantic. Finding the Allied convoys was the major problem that Admiral Döntiz had to resolve. His answer was to collect sightind radio in primarily by U-boats, collage the data, and issue orders. his was all done through coded Enigma messages and involved a huge volume of radio traffic. This made the U-boats vulnerable. Some ibformation could be obtained by directional analysis, but the motherlad was the Ultra cracking of the Enigma codes. Kreismarine Enigma operations were especially strict. And Dönitz even added an extra rotor. But the Bletchley Park code crackerseventually suceeded. This combined with technological advances, especially radar, made the Atkantgic a very dangerous place for U-boats. Code breakers were even more effective in the Pacific. he Japanese Maru code was a low-level code and compared to the Imperial Navy's JN-25 code easy to crack. And this provided one of the great inteligence bonanazea of the War. The Imperial Navy ordered each Maru to report its position daily. Thus meican code breakers could repot the position of every Maru to the Pacufic fleet submarines in their vacinity.
Battle Records
The German U-boat commanders scored impressive successes early in the War, sinking Royal Navy ships, including a battleship in of ll places Scappa Flow and an aircraft carrier. It was, however, the losses of merchant vessels that imperiled the Allied war effort. Once Dönitz got his hands n a subtantial numbe of boats as well as the ability to opeae fon French Atlantic ports (June 1940), the U'boats began to affect delivers of vital food and mterials fro the Dominions and the United States and the Bfitish were losing farmore ships than they were capable of builing. In the end, however turned the U-boats into submerible death traps. Serving on a U-boat became the most dangerous combat dury of the War. The Kreigsmarine lotv75 percent of its submarines. Destroyed U-boats and their lost crews today littered the Atlntic Ocean. Often Dönitz never knew hat happened, only that radio contact ceased and the boats never retuned to port. He would lose two sons in U-boats. The Japanese submriners achieved some success, including the sinking of several critically importat carriers at a criticalpoint of the War. The Imperial Navy, however, never committed its submarines to attacking the vulnerable Allied supply lines in the Pacific. American subrines were deployed in just such an effort, cutiing Japan off from its newly won SRZ. Had the Japanese not surrendered (August 1945), they faced mass starvation in the winter (1945-46). Unlike the Americans, the Japanese did not use their sizeable sumarine force in a commerce war. The American submarine force of about 270 ships was an almost negligibe part of the vast naval force America woulkd deploy in World War II, at about 2 percent. They account, howver, for about 50 percent of Japanese shiping losses.
Saving Downed Aimen
Boat Types
There were several diferent types of submarines. As the War progressed, the various national navies built improved types with ever increasing capabilities.
Coatal types
Fleet (ocean-going) types
Admiral Dönitz's primary weapon was the Type-IX. Fortunately for the British, OKM restricted the number of U-boats built in general as well as the number of Type IX's built until the War was well underway. The primary American submarine was the Gato-class ship, twice as large as the famed German Type-IX. This reflected both the greater American industrial capacity and the needs of a campaign waged in the vast Pacific.
Supply subs
Without control of the sea and air, submarines had to be resupplied by other submarines. Resupply extended the range and duration of patrols. The best known supply ships were the German Type XIV Milchkühe (milk cows) U-boats. As American naval and air power grew, the Japanese began to use their submarines to supply isolated island garisons. It was a huge waist of their substantial submarine force and the subs were poorly suited for the purpose.
Special purposes
Midget subs
A midget submarine is generally seen as any small submarine, often 150 tons is the size limit used to destinguish midget subs. Most midget subs had one- or two-man crews, bu there were some with six- or even eight-man crews. Thy were essebtially maned and motorized torpoes and thus built without any living accommodation. This and the the limited range of proplusion and poor stearing capabilitie meant that they were launched from mother ships. These ships brought the midget subs close to the enemy target. Their limitd capabilities meant that they could only attack targeted ships in anhor, often in closely guarded ports. The moter ships were than meant to recover the men. The Japanese were an exception here as the operations were designed from the start to be a suiside missions. The first military submarines would fall in the category of midgit submarines, but by the time of World War II were especially designed submarine types. Several countries built and used midgit submarines during the War, primarily Britain, Germany, Italy, and Japan. The gretest success was achieved by the Italians, disabling Brish ships in Alexandria (December 1941). This was a real blow to the hard-pressed Royal Navy. Perhaps the nmost famous midgit suns were the Japanese Kaiten--suiside vessels. This was after the War, during the War the Kaiten was a closly held secret. They sank an oiler in Ulithi Harbor (November 1944), but had no real impact on the War. It was, however, not for the lack of effort. The kaiten like other suiside craft, a weapon for young men. One historian writes, "Naoji Kozu also felt the training was agonizing, particularly because of its major dfference from other suiside craft. In a kaiten the mpoment of death was unknown. With other suiside weapons--like the kamikaze planrs--young men charged into the enemyh and died, but they had their eyes open and they chose the time of their death. A suiside attack by a kamikaze plane, an Ohka (cherry blossom) flying bombor a Shinyo suiside boat allowed the operator to decidethe moment of impact and death. [The katen was different,] the pilot sought the target but didn't know exactly when and where he might hit it. At the same time his body was fighing with the very difficult cintrols, his mind was tortured by not knowing when the impact woud come." [Mair and Waldron]
Sources
Mair, Michael and Joy Waldron. Kaiten: Japan's Secret Manned Suiside Sunmarine and the First American Ship It Sank in WWII (2014), 384p.
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Created: 7:40 AM 12/14/2011
Last updated: 6:02 PM 12/31/2017
