The Type IX U-boat was designed by Nazi Germany's Kriegsmarine in 1935 and 1936 as a large ocean-going submarine for sustained operations far from the home support facilities. Type IX boats were briefly used for patrols off the eastern United States in an attempt to disrupt the stream of troops and supplies bound for Europe. It was derived from the Type IA,[2][a] and appeared in various sub-types.[3]
Type IXs had six torpedo tubes; four at the bow and two at the stern. They carried six reloads internally and had five external torpedo containers (three at the stern and two at the bow) which stored ten additional torpedoes. The total of 22 torpedoes allowed U-boat commanders to follow a convoy and strike night after night. Some of the IXC boats were fitted for mine operations; as mine-layers they could carry 44 TMA or 60 TMB mines.[4]
Secondary armament was provided by one 10.5 cm (4.1 in) deck gun with 180 rounds. Anti-aircraft armament differed throughout the war. They had two periscopes in the tower. Types IXA and IXB had an additional periscope in the control room, which was removed in Type IXC and afterward.
These long range boats were frequently equipped with Focke-Achgelis Fa 330rotor kite towed rotary-wing aircraft.
Type IXB was an improved model with an increased range. It was the most successful version overall with each boat averaging a total of over 100,000 GRT sunk.
Notable IXB boats included U-123 commanded by Reinhard Hardegen, which opened up the attack in the US waters in early 1942 known as Operation Drumbeat, U-156, which was bombed by a US aircraft while flying a Red Cross-flag and rescuing survivors of a torpedoed ship (Laconia incident), and U-107 operating off Freetown, Sierra Leone under the command of Günter Hessler, which had the most successful single mission of the war ever with close to 100,000 GRT sunk.
Anengine order telegraph dial located in the engine compartment of U-505. "MT" is Maschinen Telegraf, (Telegraph Machine), and "Bb", indicating Backbord, (Port).
The Type IXC was a further refinement of the class with storage for an additional 43 tonnes of fuel, increasing the boat's range. This series omitted the control room periscope leaving the boats with two tower scopes.
As mine-layers they could carry 44 TMA or 66 TMB mines, though the 35 boats of U-162 through U-170 and U-505 through U-550 were not fitted for mine operations.[5]
DeSchiMAG AG Weser and Seebeckwerft of Bremen, and Deutsche WerftofHamburg built 54 Type IXC submarines. Only four survived the war, one of which is preserved in the US.
Type IXC/40 was an improved Type IXC with slightly increased range and surfaced speed. The remains of U-534 are on display at Woodside Ferry Terminal, Birkenhead.[7]
Type IXD was significantly longer and heavier than the IXC/40. It was faster than the IXC but at the cost of slightly reduced maneuverability. They had three pairs of Daimler Benz diesels: two pairs for cruise and one for high speed or battery recharge. There were three variants: the IXD1, IXD2 and IXD/42. The IXD1 had unreliable engines and they were later converted for use in surface transport vessels.
The IXD2 comprised most of the class and had a range of 23,700 nautical miles (43,900 km; 27,300 mi). The IXD/42, was almost identical but with more engine power (5,400 hp (4,000 kW; 5,500 PS) instead of 4,400 hp (3,300 kW; 4,500 PS)).
In 1943 and 1944 the torpedo tubes were removed from a number of IXD boats converted for transport use. In their new role they could transport 252 tonnes of cargo. The range was extended to 31,500 nautical miles (58,300 km; 36,200 mi).[1]
^"U-505 (German Submarine)". National Historic Landmark summary listing. National Park Service. Archived from the original on 12 February 2012. Retrieved 11 June 2008.
Gröner, Erich; Jung, Dieter & Maass, Martin (1991). German Warships 1815–1945. Vol. 2: U-boats and Mine Warfare Vessels. Translated by Thomas, Keith & Magowan, Rachel. London: Conway Maritime Press. ISBN0-85177-593-4.
Sharpe, Peter (1998). U-Boat Fact File: Detailed Service Histories of the Submarines Operated by the Kriegsmarine 1935-1945. Leicester: Midland Publishing. ISBN1-85780-072-9.
Showell, Jak P. Mallmann (2006). The U-boat Century: German Submarine Warfare 1906-2006. London: Chatham Publishing. ISBN9781861762412.
Thew, Robert W. (1991). "The Type IX U-Boat". Warship International. XXVIII (1). International Naval Research Organization: 14–29. ISSN0043-0374.
Rössler, Eberhard (2001). The U-boat: The evolution and technical history of German submarines. London: Cassell & Co. ISBN0-304-36120-8.
Williamson, Gordon (2005). Wolf Pack: The Story of the U-boat in World War II. Oxford: Osprey Publishing. ISBN1-84176-872-3.
