SM UC-44

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German Empire
Class and type: German Type UC II submarine
Name: UC-44
Ordered: 20 November 1915[1]
Builder: AG Vulcan, Hamburg[2]
Yard number: 77[1]
Launched: 10 October 1916[1]
Commissioned: 4 November 1916[1]
Fate: sunk by own mine, 4 August 1917[1]
General characteristics [3]
Class and type: Type UC II submarine
  • 400 t (390 long tons), surfaced
  • 480 t (470 long tons), submerged
  • 5.22 m (17 ft 2 in) o/a
  • 3.65 m (12 ft) pressure hull
Draught: 3.68 m (12 ft 1 in)
  • 11.7 knots (21.7 km/h; 13.5 mph), surfaced
  • 6.7 knots (12.4 km/h; 7.7 mph), submerged
  • 9,410 nmi (17,430 km; 10,830 mi) at 7 knots (13 km/h; 8.1 mph) surfaced
  • 60 nmi (110 km; 69 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged
Test depth: 50 m (160 ft)
Complement: 26
Notes: 48-second diving time
Service record
Part of:
  • I Flotilla
  • 1 January – 4 August 1917
  • Kptlt. Kurt Tebbenjohanns[4]
  • 4 November 1916 – 4 August 1917
Operations: 6 patrols
  • 28 merchant ships sunk (25,709 GRT)
  • 1 merchant ship taken as a prize (229 GRT)
  • 1 warship sunk (550 tons)
  • 2 warship damaged (1,250 tons)

SM UC-44 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 20 November 1915 and was launched on 10 October 1916. She was commissioned into the German Imperial Navy on 4 November 1916 as SM UC-44.[Note 1] In 6 patrols UC-44 was credited with sinking 29 ships, either by torpedo or by mines laid. UC-44 was sunk by the detonation of one of her own mines off the Irish coast at position 52°07′N 6°59′W / 52.117°N 6.983°W / 52.117; -6.983Coordinates: 52°07′N 6°59′W / 52.117°N 6.983°W / 52.117; -6.983 on 4 August 1917; its commander, Kurt Teppenjohanns, was the only survivor. UC-44's wreck was raised by the Royal Navy in September 1917 and later broken up.[1]

Two aspects of her service are noteworthy. UC-44 was the first submarine to use the tactic of releasing oil and debris from her torpedo tubes to fool the enemy into believing it had been sunk by depth charges. Her actual sinking, sometimes claimed to be the result of British deception, also yielded intelligence that showed how little effect the Dover Barrage antisubmarine defences were having on the U-boats and forced changes in its command and operation before the year ended.


A German Type UC II submarine, UC-44 had a displacement of 400 tonnes (390 long tons) when at the surface and 480 tonnes (470 long tons) while submerged. She had a length overall of 49.45 m (162 ft 3 in), a beam of 5.22 m (17 ft 2 in), and a draught of 3.68 m (12 ft 1 in). The submarine was powered by two six-cylinder four-stroke diesel engines each producing 260 metric horsepower (190 kW; 260 shp) (a total of 520 metric horsepower (380 kW; 510 shp)), two electric motors producing 460 metric horsepower (340 kW; 450 shp), and two propeller shafts. She had a dive time of 48 seconds and was capable of operating at a depth of 50 metres (160 ft).[3]

The submarine had a maximum surface speed of 11.7 knots (21.7 km/h; 13.5 mph) and a submerged speed of 6.7 knots (12.4 km/h; 7.7 mph). When submerged, she could operate for 60 nautical miles (110 km; 69 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 9,410 nautical miles (17,430 km; 10,830 mi) at 7 knots (13 km/h; 8.1 mph). UC-44 was fitted with six 100-centimetre (39 in) mine tubes, eighteen UC 200 mines, three 50-centimetre (20 in) torpedo tubes (one on the stern and two on the bow), seven torpedoes, and one 8.8 cm (3.5 in) Uk L/30 deck gun. Her complement was twenty-six crew members.[3]

Deception tactics[edit]

During a particularly intense depth charge attack on 15 February 1917, Kapitanleutnant Kurt Tebbenjohanns, UC-44's commander, ordered that the vessel's front torpedo tubes be filled with waste oil and other debris, then fired, simulating what might have been expected to reach the surface had the submarine sank. The ruse worked, and the attack was ended, allowing UC-44 to escape. Other U-boat commanders, and eventually their counterparts in other navies, adopted this deception tactic. It was particularly effective for the Germans at first, as British commanders were easily satisfied that they had sunk the enemy.[5]


In summer 1917 UC-44 was operating off Waterford Harbour on the southern coast of Ireland, laying mines and then re-laying them after British minesweepers had cleared the field. The Royal Navy officers in charge of the minesweeping surmised from the regularity with which this occurred and the haste with which the mines were laid that the Germans had broken their codes. Some of them later claimed that, realising this, they had the minesweeper run a dummy operation in mid-July, leaving all the mines in place and reporting that it had cleared them using the code suspected to have been broken, then closing the harbour to all shipping for two weeks.[6] The hope was reportedly that a stricken U-boat would sink in shallow water where it and its contents could be recovered and examined by Room 40 and other departments of naval intelligence.[7] however the historical record suggests that the British had not become aware of the compromised code and closed Waterford until after UC-44 sank.[6]

UC-44 returned to Waterford to lay nine mines on the night of 4 August. After four had been successfully deployed west of the harbour, it set out to lay the other five in the centre. As it was releasing the last, from a chute in the rear of the vessel, an explosion occurred and the submarine sank in 25 metres (82 ft) of water. Tebenjohanns and two others managed to escape through the conning tower hatch, but the commander was the only one still alive when a British vessel swept the area for survivors an hour and a half later (another account suggests that another crewmember was found separately).[6]

The British were pleasantly surprised that they had been fortunate enough to capture a U-boat commander. One officer who took tea with Tebenjohanns said the commander complained that the minesweepers had not done their jobs efficiently; they reportedly allowed him to share this news with his own superiors along with the report of his capture. When he was asked if the Germans had broken the code used by the British minesweepers, he said that as an officer he could not answer that, but the interrogator believed his demeanor and body language as he replied betrayed that the Germans had indeed done so.[6]

Navy divers later reached the wrecked submarine to sweep it for intelligence, something the British had not previously been able to do with a sunken U-boat. They described the explosion damage as concentrated around UC-44's stern and engine room, near where the mine had been released from. This, along with the other eight mines being discovered and swept, suggests that the submarine sank when one of its own mines accidentally detonated while being laid, and not due to any deception operation by the Royal Navy, or[6] as other accounts have it a leftover mine laid by UC-42[8]

Intelligence recovered from UC-44 was greatly disturbing to the Admiralty. The submarine's logs showed that U-boats were passing the Dover Barrage at will; Tebenjohanns' standing orders were to pass the net on the surface at night when possible and dive no deeper than 40 metres (130 ft) if not. U-boats that for whatever reason bypassed the English Channel entirely and went around the northern tip of Scotland were advised to do so completely on the surface since that would lead the English to think the Dover defences were working. This discovery was a contributing factor to Reginald Bacon being relieved as commander of the Dover Patrol at the end of the year.[9]

Summary of raiding history[edit]

Date Name Nationality Tonnage[Note 2] Fate[10]
11 February 1917 Ashwold  United Kingdom 129 Sunk
12 February 1917 Adolf  Sweden 835 Sunk
12 February 1917 Dale  United Kingdom 198 Sunk
13 February 1917 King Alfred  United Kingdom 159 Sunk
14 February 1917 Belvoir Castle  United Kingdom 221 Sunk
14 February 1917 Mary Bell  United Kingdom 144 Sunk
5 March 1917 Guadiana  Portugal 326 Sunk
7 March 1917 Adalands  Norway 1,577 Sunk
7 March 1917 Westwick  United Kingdom 5,694 Sunk
9 March 1917 HMS Albacore  Royal Navy 440 Damaged
12 March 1917 Lucy Anderson  United Kingdom 1,073 Sunk
12 March 1917 Marna  Norway 914 Sunk
13 March 1917 Navenby  United Kingdom 167 Sunk
13 March 1917 Nuttallia  United Kingdom 229 Captured as a prize
28 March 1917 Ruby  United Kingdom 234 Sunk
13 April 1917 Bandon  United Kingdom 1,456 Sunk
15 April 1917 Dalmatian  United Kingdom 186 Sunk
15 April 1917 Heikina  Netherlands 157 Sunk
15 April 1917 Sutterton  United Kingdom 160 Sunk
19 April 1917 Poltava  United Kingdom 945 Sunk
20 April 1917 Erith  United Kingdom 168 Sunk
20 April 1917 Grecian  United Kingdom 119 Sunk
21 April 1917 Peik  Norway 701 Sunk
22 April 1917 Nightingale  United Kingdom 91 Sunk
23 April 1917 Auriac  United Kingdom 871 Sunk
23 April 1917 Baron Stjernblad  Denmark 991 Sunk
23 April 1917 Scot  Denmark 1,564 Sunk
28 May 1917 Turid  Norway 1,148 Sunk
30 June 1917 Asalia  Norway 2,348 Sunk
30 June 1917 Phoebus  Kingdom of Italy 3,133 Sunk
6 July 1917 HMS Itchen  Royal Navy 550 Sunk

See also[edit]



  1. ^ "SM" stands for "Seiner Majestät" (English: His Majesty's) and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.
  2. ^ Merchant ship tonnages are in gross register tons. Military vessels are listed by tons displacement.


  1. ^ a b c d e f Helgason, Guðmundur. "WWI U-boats: UC 44". German and Austrian U-boats of World War I - Kaiserliche Marine - Retrieved 23 February 2009.
  2. ^ Tarrant, p. 173.
  3. ^ a b c Gröner 1991, pp. 31-32.
  4. ^ Helgason, Guðmundur. "WWI U-boat commanders: Kurt Tebbenjohanns". German and Austrian U-boats of World War I - Kaiserliche Marine - Retrieved 23 February 2015.
  5. ^ Henry, Chris (2005). Depth Charge!: Mines, Depth Charges and Underwater Weapons, 1914-1945. Casemate Publishers. pp. 71–72. ISBN 9781844151745. Retrieved 8 August 2017.
  6. ^ a b c d e Grant, Robert (2003). U-boat Hunters: Code Breakers, Divers and the Defeat of the U-boats, 1914-1918. Periscope Publishing. pp. 54–55. ISBN 9781904381150. Retrieved 8 August 2017.
  7. ^ Nolan, Liam; Nolan, John E. (2009). Secret Victory: Ireland and the War at Sea, 1914-1918. Mercier Press Ltd. p. 235. ISBN 9781856356213. Retrieved 8 August 2017.
  8. ^ McGreal, Stephen (2008). Zeebrugge and Ostend Raids. Pen and Sword. p. 14. ISBN 9781783460953. Retrieved 8 August 2017.
  9. ^ Gray, Edwyn A. (1994). The U-Boat War: 1914-1918. Pen and Sword. p. 202. ISBN 9781473820043. Retrieved August 8, 2017.
  10. ^ Helgason, Guðmundur. "Ships hit by UC 44". German and Austrian U-boats of World War I - Kaiserliche Marine - Retrieved 23 February 2015.


  • Bendert, Harald (2001). Die UC-Boote der Kaiserlichen Marine 1914-1918. Minenkrieg mit U-Booten (in German). Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0758-7.
  • Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
  • Gardiner, Robert, ed. (1985). Conway's All the World's Fighting Ships, 1906–1921. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-907-8. OCLC 12119866.
  • Tarrant, V. E. (1989). The U-Boat Offensive: 1914–1945. Annapolis, Maryland: Naval Institute Press. ISBN 978-0-87021-764-7. OCLC 20338385.