# SM U-39

SM U-39 was a German Type U 31 U-boat which operated in the Mediterranean Sea during World War I. It ended up being the second most successful U-boat participating in the war, sinking 149 merchant ships for a total of 404,774 GRT.
Its longest-serving captain was Kapitänleutnant Walther Forstmann, who was awarded the Pour le Mérite during command on U-39.
From January to mid-1917, Martin Niemöller served as U-39's coxswain. He is known as the author of the 1946 poem "First they came..."; as an enemy of the Third Reich, he was imprisoned from 1938 to 1945. In 1917 and 1918, Karl Dönitz served as watch officer on this boat. He later became Grand Admiral and Commander in Chief of the German Navy, and, for three weeks following Hitler's death, the head of the remnants of the Nazi government.

## Design

Type U 31 submarines were double-hulled ocean-going submarines similar to Type 23 and Type 27 subs in dimensions and differed only slightly in propulsion and speed. They were considered very good high sea boats with average manoeuvrability and good surface steering.
U-39 had an overall length of 64.70 m (212 ft 3 in), her pressure hull was 52.36 m (171 ft 9 in) long. The boat's beam was 6.32 m (20 ft 9 in) (o/a), while the pressure hull measured 4.05 m (13 ft 3 in). Type 31s had a draught of 3.56 m (11 ft 8 in) with a total height of 7.68–8.04 m (25 ft 2 in – 26 ft 5 in). The boats displaced a total of 971 tonnes (956 long tons); 685 t (674 long tons) when surfaced and 878 t (864 long tons) when submerged.
U-39 was fitted with two Germania 6-cylinder two-stroke diesel engines with a total of 1,850 metric horsepower (1,361 kW; 1,825 bhp) for use on the surface and two Siemens-Schuckert double-acting electric motors with a total of 1,200 PS (883 kW; 1,184 shp) for underwater use. These engines powered two shafts each with a 1.60 m (5 ft 3 in) propeller, which gave the boat a top surface speed of 16.4 knots (30.4 km/h; 18.9 mph), and 9.7 knots (18.0 km/h; 11.2 mph) when submerged. Cruising range was 8,790 nautical miles (16,280 km; 10,120 mi) at 8 knots (15 km/h; 9.2 mph) on the surface, and 80 nmi (150 km; 92 mi) at 5 knots (9.3 km/h; 5.8 mph) under water. Diving depth was 50 m (164 ft 1 in).
The U-boat was armed with four 50 cm (20 in) torpedo tubes, two fitted in the bow and two in the stern, and carried 6 torpedoes. Additionally U-39 was equipped in 1915 with one 8.8 cm (3.5 in) Uk L/30 deck gun, which was replaced with a 10.5 cm (4.1 in) in 1916/17. The boat's complement was 4 officers and 31 enlisted.

## Fate

On 27 April 1918, U-39 sailed from Pola under command of Kapitänleutnant Heinrich Metzger, for operations in the Western Mediterranean. On 17 May, together with SM UB-50, U-39 operated against a convoy North of Oran, from which it sank the British steamer Sculptor (4,874 GRT) in a submerged attack.
At 13:50 on 18 May, when in a position 36°36′N 00°02′W﻿ / ﻿36.600°N 0.033°W﻿ / 36.600; -0.033, U-39 was attacked by two French seaplanes. It crash-dived, but when reaching a depth of 12 meters two bombs exploded very close; the after torpedo room flooded, the diving planes were destroyed, and the boat began sinking by the stern. Kptlt. Metzger ordered the tanks blown and U-39 surfaced, but the heavy damage suffered prevented diving again. Metzger was forced to lay a course for the nearest Spanish harbour, Cartagena.
At about 17:00, U-39 was attacked again by two seaplanes; it fought back with gun and machine-guns, and the enemy bombs caused no damage, but during the action two crewmen (sailor Schulz and stoker Hausottl) fell overboard and were lost.
In the evening U-39 reached Cartagena and was interned for the remainder of the war.
It was surrendered to France on 22 March 1919 and was broken up at Toulon in 1923.

## Summary of raiding history

| Date | Name | Nationality | Tonnage | Fate |
| 1 May 1915 | Balduin | Norway | 1,059 | Sunk |
| 1 May 1915 | Elsa | Sweden | 120 | Sunk |
| 2 May 1915 | St. Louis No. 1 | United Kingdom | 211 | Sunk |
| 2 May 1915 | Sunray | United Kingdom | 165 | Sunk |
| 3 May 1915 | Scottish Queen | United Kingdom | 125 | Sunk |
| 4 May 1915 | Elsa | Sweden | 329 | Sunk |
| 5 May 1915 | Sceptre | United Kingdom | 166 | Sunk |
| 6 May 1915 | Truro | United Kingdom | 836 | Sunk |
| 7 May 1915 | Benington | United Kingdom | 131 | Sunk |
| 10 May 1915 | Olga | Denmark | 798 | Captured as prize |
| 26 June 1915 | Campania | United Kingdom | 167 | Sunk |
| 29 June 1915 | Cambuskenneth | Norway | 1,924 | Sunk |
| 29 June 1915 | Kotka | Norway | 952 | Damaged |
| 30 June 1915 | Lomas | United Kingdom | 3,048 | Sunk |
| 1 July 1915 | Caucasian | United Kingdom | 4,656 | Sunk |
| 1 July 1915 | Craigard | United Kingdom | 3,286 | Sunk |
| 1 July 1915 | Gadsby | United Kingdom | 3,497 | Sunk |
| 1 July 1915 | Inglemoor | United Kingdom | 4,331 | Sunk |
| 1 July 1915 | Richmond | United Kingdom | 3,214 | Sunk |
| 2 July 1915 | Hirondelle | France | 183 | Sunk |
| 2 July 1915 | Boduognat | Belgium | 1,411 | Sunk |
| 2 July 1915 | City of Edinburgh | United Kingdom | 6,255 | Damaged |
| 3 July 1915 | Fiery Cross | Norway | 1,448 | Sunk |
| 3 July 1915 | Larchmore | United Kingdom | 4,355 | Sunk |
| 3 July 1915 | Renfrew | United Kingdom | 3,488 | Sunk |
| 4 July 1915 | Anglo-Californian | United Kingdom | 7,333 | Damaged |
| 2 September 1915 | William T. Lewis | United Kingdom | 2,166 | Damaged |
| 9 September 1915 | Cornubia | United Kingdom | 1,736 | Sunk |
| 9 September 1915 | L’Aude | France | 2,232 | Sunk |
| 9 September 1915 | Ville De Mostaganem | France | 2,648 | Sunk |
| 28 September 1915 | H. C. Henry | Canada | 4,219 | Sunk |
| 29 September 1915 | Haydn | United Kingdom | 3,923 | Sunk |
| 30 September 1915 | Cirene | Kingdom of Italy | 3,236 | Sunk |
| 2 October 1915 | Sailor Prince | United Kingdom | 3,144 | Sunk |
| 7 October 1915 | Halizones | United Kingdom | 5,093 | Sunk |
| 8 October 1915 | Thorpwood | United Kingdom | 3,184 | Sunk |
| 9 October 1915 | Apollo | United Kingdom | 3,774 | Sunk |
| 12 October 1915 | HMD Restore | Royal Navy | 93 | Sunk |
| 30 November 1915 | Middleton | United Kingdom | 2,506 | Sunk |
| 3 December 1915 | Dante | Kingdom of Italy | 889 | Sunk |
| 3 December 1915 | Helmsmuir | United Kingdom | 4,111 | Sunk |
| 5 December 1915 | Petrolite | United States | 3,710 | Damaged |
| 5 December 1915 | Pietro Lofaro | Kingdom of Italy | 517 | Sunk |
| 6 December 1915 | L. G. Goulandris | Greece | 2,123 | Sunk |
| 7 December 1915 | Veria | United Kingdom | 3,229 | Sunk |
| 9 December 1915 | Busiris | United Kingdom | 2,705 | Sunk |
| 9 December 1915 | Orteric | United Kingdom | 6,535 | Sunk |
| 10 December 1915 | Porto Said | Kingdom of Italy | 5,301 | Sunk |
| 18 December 1915 | HMD Lottie Leask | Royal Navy | 94 | Sunk |
| 22 January 1916 | Norseman | United Kingdom | 9,542 | Sunk |
| 31 March 1916 | Egeo | Kingdom of Italy | 1,787 | Sunk |
| 31 March 1916 | Riposto | Kingdom of Italy | 1,003 | Sunk |
| 2 April 1916 | Simla | United Kingdom | 5,884 | Sunk |
| 3 April 1916 | Clan Campbell | United Kingdom | 5,897 | Sunk |
| 4 April 1916 | Giuseppe Padre | Kingdom of Italy | 184 | Sunk |
| 4 April 1916 | Maria Carmella Findari | Kingdom of Italy | 42 | Sunk |
| 6 April 1916 | Stjerneborg | Denmark | 1,592 | Sunk |
| 6 April 1916 | Colbert | France | 5,394 | Damaged |
| 9 April 1916 | Caledonia | Denmark | 1,815 | Sunk |
| 13 April 1916 | Lipari | Kingdom of Italy | 1,539 | Sunk |
| 20 May 1916 | Redentore | Kingdom of Italy | 228 | Sunk |
| 20 May 1916 | Valsesia | Kingdom of Italy | 248 | Sunk |
| 21 May 1916 | Birmania | Kingdom of Italy | 2,384 | Sunk |
| 21 May 1916 | Rosalia Madre | Kingdom of Italy | 251 | Sunk |
| 23 May 1916 | Hercules | Kingdom of Italy | 2,704 | Sunk |
| 23 May 1916 | Maria Porto Di Salvezza | Kingdom of Italy | 39 | Sunk |
| 23 May 1916 | Teresa Accame | Kingdom of Italy | 4,742 | Damaged |
| 23 May 1916 | Washington | Kingdom of Italy | 2,819 | Sunk |
| 24 May 1916 | Aurrera | Spain | 2,845 | Sunk |
| 25 May 1916 | Fratelli Bandiera | Kingdom of Italy | 3,506 | Sunk |
| 25 May 1916 | Rita | Kingdom of Italy | 200 | Sunk |
| 27 May 1916 | Mar Terso | Kingdom of Italy | 3,778 | Sunk |
| 27 May 1916 | Trunkby | United Kingdom | 2,635 | Sunk |
| 28 May 1916 | Lady Ninian | United Kingdom | 4,297 | Sunk |
| 29 May 1916 | Baron Vernon | United Kingdom | 1,779 | Sunk |
| 29 May 1916 | Elmgrove | United Kingdom | 3,018 | Sunk |
| 29 May 1916 | Southgarth | United Kingdom | 2,414 | Sunk |
| 30 May 1916 | Baron Tweedmouth | United Kingdom | 5,007 | Sunk |
| 30 May 1916 | Dalegarth | United Kingdom | 2,265 | Sunk |
| 30 May 1916 | Hermesberg | Kingdom of Italy | 2,884 | Sunk |
| 30 May 1916 | Rauma | Norway | 3,047 | Sunk |
| 1 June 1916 | Dewsland | United Kingdom | 1,993 | Sunk |
| 1 June 1916 | Salmonpool | United Kingdom | 4,905 | Sunk |
| 13 July 1916 | Silverton | United Kingdom | 2,682 | Sunk |
| 14 July 1916 | Antigua | United Kingdom | 2,876 | Sunk |
| 14 July 1916 | Ecclesia | United Kingdom | 3,714 | Sunk |
| 15 July 1916 | Sylvie | United Kingdom | 1,354 | Sunk |
| 16 July 1916 | Euphorbia | United Kingdom | 3,837 | Sunk |
| 16 July 1916 | Sirra | Kingdom of Italy | 3,203 | Sunk |
| 16 July 1916 | Wiltonhall | United Kingdom | 3,387 | Sunk |
| 17 July 1916 | Angelo | Kingdom of Italy | 3,609 | Sunk |
| 17 July 1916 | Rosemoor | United Kingdom | 4,303 | Sunk |
| 18 July 1916 | Llongwen | United Kingdom | 4,683 | Sunk |
| 20 July 1916 | Cettois | France | 974 | Sunk |
| 20 July 1916 | Grangemoor | United Kingdom | 3,198 | Sunk |
| 20 July 1916 | Karma | United Kingdom | 3,710 | Sunk |
| 20 July 1916 | Yzer | United Kingdom | 3,538 | Sunk |
| 21 July 1916 | Wolf | United Kingdom | 2,443 | Sunk |
| 22 July 1916 | Knutsford | United Kingdom | 3,842 | Sunk |
| 22 July 1916 | Olive | United Kingdom | 3,678 | Sunk |
| 23 July 1916 | Badminton | United Kingdom | 3,847 | Sunk |
| 24 July 1916 | Maria | Kingdom of Italy | 198 | Sunk |
| 29 July 1916 | Letimbro | Kingdom of Italy | 2,210 | Sunk |
| 29 July 1916 | Rosarina G.V. | Kingdom of Italy | 131 | Sunk |
| 19 October 1916 | Penylan | United Kingdom | 3,875 | Sunk |
| 20 October 1916 | Mombassa | United Kingdom | 4,689 | Sunk |
| 22 October 1916 | Cluden | United Kingdom | 3,166 | Sunk |
| 22 October 1916 | Nina | Kingdom of Italy | 3,383 | Sunk |
| 22 October 1916 | Ravn | Norway | 998 | Sunk |
| 22 October 1916 | W. Harkess | United Kingdom | 1,185 | Sunk |
| 27 November 1916 | Margarita | Greece | 1,112 | Sunk |
| 27 November 1916 | Reapwell | United Kingdom | 3,417 | Sunk |
| 28 November 1916 | King Malcolm | United Kingdom | 4,351 | Sunk |
| 28 November 1916 | Moresby | United Kingdom | 1,763 | Sunk |
| 2 December 1916 | Istrar | United Kingdom | 4,582 | Sunk |
| 3 December 1916 | Plata | Kingdom of Italy | 1,861 | Sunk |
| 9 January 1917 | Baynesk | United Kingdom | 3,286 | Sunk |
| 15 January 1917 | Garfield | United Kingdom | 3,838 | Sunk |
| 28 January 1917 | Amiral Magon | France | 5,566 | Sunk, 203 people killed |
| 14 February 1917 | Torino | Kingdom of Italy | 4,159 | Sunk |
| 15 February 1917 | Minas | Kingdom of Italy | 2,854 | Sunk, 870 people killed |
| 17 February 1917 | Ala | Kingdom of Italy | 359 | Sunk |
| 20 February 1917 | Rosalie | United Kingdom | 4,237 | Sunk |
| 21 February 1917 | Wathfield | United Kingdom | 3,012 | Sunk |
| 22 February 1917 | Ville De Bougie | France | 508 | Sunk |
| 23 February 1917 | Trojan Prince | United Kingdom | 3,196 | Sunk |
| 26 February 1917 | Burnby | United Kingdom | 3,665 | Sunk |
| 3 March 1917 | S. Anna S. | Kingdom of Italy | 41 | Sunk |
| 3 June 1917 | Petronilla Madre | Kingdom of Italy | 43 | Sunk |
| 6 June 1917 | Diane | France | 590 | Sunk |
| 8 June 1917 | Huntstrick | United Kingdom | 8,151 | Sunk |
| 8 June 1917 | Isle Of Jura | United Kingdom | 3,809 | Sunk |
| 8 June 1917 | HMML 540 | Royal Navy | 37 | Sunk |
| 8 June 1917 | HMML 541 | Royal Navy | 37 | Sunk |
| 8 June 1917 | Valdieri | Kingdom of Italy | 4,637 | Sunk |
| 10 June 1917 | Petrolite | United States | 3,710 | Sunk |
| 11 June 1917 | Wera | Russian Empire | 476 | Sunk |
| 12 June 1917 | Gaita | Russian Empire | 396 | Sunk |
| 15 June 1917 | Espinho | Portugal | 740 | Sunk |
| 19 June 1917 | Kyma | Greece | 3,420 | Sunk |
| 20 June 1917 | Eli Lindoe | Norway | 1,116 | Sunk |
| 22 June 1917 | Toro | Uruguay | 1,141 | Sunk |
| 23 June 1917 | Isere | France | 2,159 | Sunk |
| 29 July 1917 | Manchester Commerce | United Kingdom | 4,144 | Sunk |
| 30 July 1917 | Carlo | Kingdom of Italy | 5,572 | Sunk |
| 30 July 1917 | Ganges | United Kingdom | 4,177 | Sunk |
| 31 July 1917 | Carolvore | Norway | 1,659 | Sunk |
| 31 July 1917 | Ypres | United Kingdom | 305 | Sunk |
| 3 August 1917 | Halldor | Norway | 2,919 | Sunk |
| 5 August 1917 | Ryton | United Kingdom | 3,991 | Sunk |
| 27 September 1917 | Swan River | United Kingdom | 4,724 | Sunk |
| 1 October 1917 | Mersario | United Kingdom | 3,847 | Sunk |
| 1 October 1917 | Normanton | United Kingdom | 3,862 | Sunk |
| 2 October 1917 | Almora | United Kingdom | 4,385 | Sunk |
| 2 October 1917 | Hikosan Maru | Japan | 3,555 | Sunk |
| 2 October 1917 | Nuceria | United Kingdom | 4,702 | Sunk |
| 14 November 1917 | Buenaventura | Spain | 257 | Sunk |
| 18 November 1917 | HMS Candytuft | Royal Navy | 1,290 | Sunk |
| 21 November 1917 | Schuylkill | United States | 2,720 | Sunk |
| 23 November 1917 | Markella | Greece | 1,124 | Sunk |
| 25 November 1917 | Karema | United Kingdom | 5,263 | Sunk |
| 17 May 1918 | Sculptor | United Kingdom | 4,874 | Sunk |