Type IX U-Boat
Ocean-Going Attack Submarine
The Type IX brought together many key features that would make it one of the more successful German wartime U-Boat designs.
Authored By: Dan Alex | Last Edited:
The German Kriegsmarine paid a heavy price for their actions in World War 2, with most of her Type IX class being lost to the sea, most times with all hands aboard. The Type IX made up an effective fighting force, particularly in the opening years of the war, and her presence was felt throughout the remainder of the conflict with some 283 examples being completed and seeing service - this total making up the second largest class of U-boats after the Type VII. The vessel offered excellent range, a potent armament and durability that afforded her operations in the unforgiving rough waters of the Atlantic. She was classified for ocean warfare and, to her crews, she did not disappoint. Her own class produced four distinct sub-variants, each with improvements throughout. The Type IX was preceded by the Type VII class U-Boat.
The Type IX was derived from the World War I-era MS boats and was developed from the earlier Type IA class of 1934-1935. The new type was differentiated by its use of a double hull construction. The double hull construction allowed for greater internal capacities by positioning fuel stores and ballast tanks outside of the main hull and inside of a second watertight hull. Additionally, this hull design provided for greater survivability for the crew and ship structure alike, able to absorb potentially lethal explosive forces more efficiently. The design also made for a more robust performer when operating in the volatile surface elements. The Type IX saw her torpedo count increased to twenty-two, along with her six tubes, making her a lethal performer on any scale. Despite this offensive punch, the main goal in the Type IX design was in the improving of a U-boats operational range. The proceeding design success came at the cost of decreased maneuverability and increased dive times.
The Allies were making great use of the Atlantic Ocean waterways to shuffle troops, arms and supplies to Europe for use against German interests and both German leader Adolf Hitler and British Prime Minister Winston Churchill knew the value of winning the war along this front. Germany began developing long range submarines to counter the growing threat of American involvement in the war and developed such boats with enough endurance to spy on and engage vessels along the eastern coast of the United States.
From the start of the war, Type IXs were seen in action across the Atlantic and concentrated their efforts along the eastern seaboard of America as well as in actions in the south Atlantic. The main targets became the unprotected shipping that traversed the Atlantic and, at this time, had yet to incorporate suitable self-defense armament or become part of any concentrated convoy strategy. While finding successes in this venture, Type IXs were eventually replaced in this role by the Type VIIC class. Allied countermeasures improved substantially as the war progressed with the addition of radar and sonar systems as well as patrols by air becoming ever more common and concentrated, putting the U-boats on the defensive. Convoys and escorts also contributed to the many losses of U-boat crews by war's end.
The Type IX class as a whole sported a sleek, elongated and streamlined form consistent with the time. The fin was set approximately amidships with the deck gun positioned just forward of the tower (the gun sometimes omitted). The tower itself held the anti-aircraft armament to allow for quick reactions by the gunnery crew. Both of these emplacements were set in an aft-facing direction in trainable mounts. The sail was fitted with the applicable periscope and sighting fixtures. Vents dotted the long-running sides of the Type IX design. The upper surface of the hull was flat to allow for crew to traverse her topside while the sides bulged outwardly ever so slightly to incorporate the needed internal compartments. The design tapered into a streamlined spine along the bottom of the hull, suitable for cutting through the deep ocean water. The twin shafts were set to the stern, one system to either hull side, each capped with a three-bladed propeller. The rudder component was set under the stern and controlled the submarine's side-to-side maneuvering as required. Anchors were positioned along the bow sides. There were six total torpedo tube bays with four of these fitted along the bow sides and two in stern side positions. A snorkel allowed the Type IX to recharge her batteries while remaining submerged just under the surface of the water. The crew complement was made up of 48 personnel - four officers and forty-four Kriegsmarine sailors.
Armament (Type IXC) centered around the 533mm (21-inch) torpedo. Able to carry 22 of these and coupled with the Type IXs endurance, the vessel could stay in the field for long periods of time while locating and shadowing enemy convoys and ships, striking at the most opportune time (along the surface, usually at night). Six reload torpedoes were held internally with the rest held in external torpedo "carriers" - two such provisions mounted to the bow and the remaining three at the stern numbering some 10 additional torpedoes. With each tube filled and ready to fire (6, four forward and two aft), the total count with the reserves numbered 22 torpedoes.
The deck gun consisted of a single Utof 105mm/45 cannon with 110 available projectiles and was suitable in engaging unarmed or lightly armed surface vessels when possible. The submarine (Type IXC) was defensed by a 37mm anti-aircraft cannon in a single trainable fitting as well as a 20mm anti-aircraft cannon, also in a single trainable fitting. The anti-aircraft gun systems were situated in a stepped fashion along the rear of the sail and, in this setup, offered up an excellent arcs of fire. Of note, however, is that this anti-aircraft arrangement varied on the Type IX boats throughout the course of the war. For example, sometimes the deck gun was given up in favor of an additional Flak system and some single 20mm mounts became quad-mountings instead.
If using the Type IXC as our continued example the vessel was given a top surface speed of 18.2 knots with a submerged speed of 7.5 knots. Her operational range was in the vicinity of 15,535 miles along the surface and roughly 72 miles when submerged. Dimensions included a near-252 feet length, a 22 feet, 2 inch beam and a 15 feet, 5 inch draught. Her displacement was 1,120 tons surfaced and 1,232 tons when submerged. Power on the surface was delivered from twin MAN M9V40/46 supercharged, 9-cylinder diesel engines at 4,400 horsepower. Submerged battery power came from a pair of SSW GU345/34 double-acting electric motors running at 1,000 horsepower. These systems provided propulsion to two propeller shafts held at the stern of the design.
The Type IXA was the first in the Type IX class. Eight such boats were constructed by DeSchiMAG (AG Weser) of Bremen, Germany, seeing service from 1938 to 1939. AG Weser played a major role in the construction of German U-boats in World War 1 and, by this time, had been merged along with eight other shipyards in Germany to become a part of the Deutsche Schiffund Maschinenbau AG (DeSchiMAG), though the AG Weser name was allowed to continue as an independent brand identifier. The shipyard would eventually survive the war and continue production of various maritime vessels up until closure on December 31st, 1983.
Type IXA U-boats ranged from U-37 to U-44. Armament was six torpedo tubes, 1 x 10.5cm deck gun, 1 x 3.7cm Flak gun and 1 x 2cm Flak gun. Her 22 torpedoes could be replaced with 66 mines. From 1943 to 1944, the 10.5cm deck was often omitted and replaced with an additional Flak gun. Of the eight vessels put to sea, six were sunk from 1939 to 1943 while two were scuttled in May of 1945 (U-37 and U-38).
As the Type IXA series was earning its run on the waters, the Type IXB was already being developed. This series encompassed some 14 total boats ranging from U-64 and U-65, U-103 to U-111 and U-122 to U-124 with service running from 1939 to 1940. These submarines were also produced by AG Weser at the Bremen shipyard. Essentially, the Type IXB was an improved class of boat that sought to further improve the operational ranges inherent to the Type IXA design. By the end of it all, the Type IXB group would prove the most successful of all the Type IX series and leave many-a-U-Boat ace to her legacy. The 22 onboard torpedoes could be replaced with 66 mines. Nearly all Type IXB boats could account for an average of 100,000 tons of goods sunk by the war's end. All Type IXB systems were lost with the exception of U-123, her being decommissioned on June 17th, 1944 at Lorient.
The Type IXC was introduced into the series line and quickly became the largest operating group of Type IXC boats. Construction was yet again handled by AG Weser and 54 of its type were produced during the war. The Type IXC was fitted with additional internal fuel stores to further improve the submarine's range. Type IXCs could also be fitted as minelayers and make use of 66 TMB or 44 TMA series mines though most were usually not fitted as such. This group encompassed U-66 through U-68, U-126 through U-131, U-153 through U-166, U-171 through U-176 and U-501 through U-533.
The Type IXC was little bettered in the Type IXC/40 group. These boats were given improved ranges and surface speeds and numbered 87 in total. Construction was handled by AG Weser, Deutsche Werft (Hamburg) and Seebeckwerft (Bremen). There U-boats were U-167 to U-170, U-183 to U-550, U-801 to U-806, U-841 to U-846, U-853 to U-858, U-865 to U-889 and U-1221 to U-1235.
Most all Type IXCs were sunk by the end of the war. Service for the Type IXC ran from 1941 to 1942 while the Type IXC/40 was commissioned from 1942 to 1944.
With development beginning as early as 1940, the Type IXD was put to sea by 1942. These boats were given an extra 35.4 feet of hull length for which to work with. Three subvariants made up the Type IX variant itself and were designated as the IXD1, IXD2 and the IXD2/42.
Two Type IXD1 examples were delivered (U-180 and U-195), but these lacked any viable armament (no torpedoes, just the deck gun and seven Flak cannons), used instead as ocean-going refueling vessels for other U-boats in operation. Type IXD1s could haul some 250 tons of fuel and were faulted for their inconsistent experimental diesel engines - the latter implementation was not used in further Type IXDs that were to follow. The engines were 6 x 20-cylinder, four-stroke Mercedes-Benz MB501 "Vee" diesel systems generating an impressive 9,000 horsepower. These were later replaced by a pair of 6-cylinder, four-stroke Germaniawerft F46 super-charged diesel engines. Submerged power came from 2 x SSW GU345/54 double-acting motors generating 740kW. U-180 was lost west of Bordeaux on August 24th, 1944 and U-195 was taken over by the Japanese on May 6th, 1945.
The Type IXD2 comprised of 28 boats and made up the larger part of the Type IXD class as a whole. These put forth ever increasing operational ranges topping off at an impressive 36,290 miles. Type IXD2s were able to reach operations as far away as Japan and the Indian Ocean, making it one of the more lethal U-Boat systems to date. The torpedo count increased to 24 (or 72 mines in their place). Operations ran from 1942 to 1944 with most sunk before the end of the war.
The Type IXD2/42 was nearly identical to the preceding Type IXD2s but were given improved engines with greater output - approximately 1,000 more horsepower than in the original Type IXD2s. Only two IXD2/42 systems were reportedly made available for service. U-884 was damaged by Allied bombs while still in the dockyard on March 30th, 1945. U-883 surrendered on June 21st, 1945 at Wilhelmshaven.
Type IXD submarines were made up of the U-177 to U-182, U-195 to U-200, U-847 to U-852, U-859 to U-864 and U-871 to U-876. U-883 and U-884 were the only two IXD2/42 completed. U-885, U-886, U-887 and U-888 had begun construction but their progress was cancelled in whole on September 30th, 1943 when the IXD2/42 contract was itself cancelled. From 1943 to 1944, the torpedo tubes were removed from many of the Type IXDs in circulation.
U-505, a Type IXC U-Boat can be seen in all her glory at the Museum of Science and Industry in Chicago, Illinois, USA. She was fully restored in 2005. The only other Type ICX preserved is the U-534, available for viewing in Birkenhead, England, UK.
The Type IX was eventually succeeded by the Type X class U-Boat.