|Ordered:||15 September 1915|
|Laid down:||12 January 1916|
|Launched:||15 December 1916|
|Commissioned:||10 February 1917|
|Fate:||Lost to unknown cause off Hardelot, France in January 1918.|
|Class and type:||German Type U 93 submarine|
|Height:||8.25 m (27 ft 1 in)|
|Draught:||3.94 m (12 ft 11 in)|
|Propulsion:||2 shafts, 2 × 1.66 m (5 ft 5 in) propellers|
|Test depth:||50 m (160 ft)|
|Complement:||4 officers, 32 enlisted|
German Type U 93 submarines were preceded by the shorter Type U 87 submarines. U-93 had a displacement of 838 tonnes (825 long tons) when at the surface and 1,000 tonnes (980 long tons) while submerged. She had a total length of 71.55 m (234 ft 9 in), a pressure hull length of 56.05 m (183 ft 11 in), a beam of 6.30 m (20 ft 8 in), a height of 8.25 m (27 ft 1 in), and a draught of 3.94 m (12 ft 11 in). The submarine was powered by two 2,400 metric horsepower (1,800 kW; 2,400 shp) engines for use while surfaced, and two 1,200 metric horsepower (880 kW; 1,200 shp) engines for use while submerged. She had two propeller shafts. She was capable of operating at depths of up to 50 metres (160 ft).
The submarine had a maximum surface speed of 16.8 knots (31.1 km/h; 19.3 mph) and a maximum submerged speed of 8.6 knots (15.9 km/h; 9.9 mph). When submerged, she could operate for 52 nautical miles (96 km; 60 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, she could travel 9,020 nautical miles (16,710 km; 10,380 mi) at 8 knots (15 km/h; 9.2 mph). U-93 was fitted with six 50 centimetres (20 in) torpedo tubes (four at the bow and two at the stern), twelve to sixteen torpedoes, and one 8.8 cm (3.5 in) SK L/30 deck gun. She had a complement of thirty-six (thirty-two crew members and four officers).
Since February 1917 she was commanded by the late author of books (e.g. U boat 202. The war diary of a German submarine, 1919) and experienced submarine commander Edgar von Spiegel von und zu Peckelsheim
On 30 April 1917 about 180 nautical miles (330 km; 210 mi) south of Ireland, in the Atlantic, U-93 attacked HMS Prize, a three-masted topsail schooner (one of the Q ships) commanded by Lieutenant William Edward Sanders (who received a Victoria Cross for the action). HMS Prize was damaged by shellfire. After the 'panic party' had taken to the boats and the ship appeared to be sinking, the U-boat approached to within 80 yards (73 m) of her port quarter, whereupon the White Ensign was hoisted and the Prize opened fire.
Within a few minutes the submarine was on fire and her bows rose in the air, whilst the Prize was further damaged. The U-boat disappeared from sight, and was believed to have been sunk by the crew of the Prize and by several of the German crew (including her captain) who had been blown or jumped into the sea.
Neither of the crippled ships had sunk, with the Prize being towed in flames back to Kinsale, while the U-93 struggled back to the Sylt nine days later after a dramatic escape effort through the British mine and destroyer barrages off Dover.
Summary of raiding history
|15 April 1917||Fram||105||Sunk|
|18 April 1917||Troldfos||1,459||Sunk|
|18 April 1917||West Lothian||1,887||Sunk|
|22 April 1917||Vestelv||1,729||Sunk|
|28 April 1917||Diana||207||Damaged|
|29 April 1917||Comedian||4,889||Sunk|
|29 April 1917||Ikbal||5,434||Sunk|
|30 April 1917||Ascaro||3,245||Sunk|
|30 April 1917||Horsa||2,949||Sunk|
|30 April 1917||Parthenon||2,934||Sunk|
|30 April 1917||HMS Prize||199||Damaged|
|19 June 1917||Louise||645||Sunk|
|27 June 1917||Baron Ogilvy||4,570||Sunk|
|4 July 1917||Kodan||308||Sunk|
|12 August 1917||Bestum||3,520||Sunk|
|14 August 1917||Asti||5,300||Sunk|
|20 August 1917||Elswick Lodge||3,558||Sunk|
|21 August 1917||Volodia||5,689||Sunk|
|23 August 1917||Carl F. Cressy||898||Sunk|
|25 August 1917||Heatherside||2,767||Sunk|
|25 August 1917||Ovar||1,650||Sunk|
|26 August 1917||Marmion||4,066||Sunk|
|26 August 1917||Minas Queen||492||Sunk|
|29 August 1917||Treloske||3,071||Sunk|
|18 October 1917||Macao||3,557||Sunk|
|27 October 1917||D. N. Luckenbach||2,929||Sunk|
|28 October 1917||USAT Finland||12,222||Damaged|
|29 October 1917||La Epoca||2,432||Sunk|
|30 October 1917||Liff||2,521||Sunk|
|2 January 1918||Veda||25||Sunk|
|4 January 1918||Goeland I||235||Sunk|
|6 January 1918||Kanaris||3,793||Sunk|
|6 January 1918||Harry Luckenbach||2,798||Sunk|
|6 January 1918||Henri Lecour||2,488||Sunk|
|6 January 1918||Dagny||1,220||Sunk|
|14 January 1918||Babin Chevaye||2,174||Sunk|
|15 January 1918||War Song||2,535||Sunk|
- Innes McCartney (2015). The Maritime Archaeology of a Modern Conflict: Comparing the Archaeology of German Submarine Wrecks to the Historical Text. New York: Routledge. pp. 117–119. ISBN 978-1138814356.
- Gröner 1991, pp. 12-14.
- Helgason, Guðmundur. "WWI U-boats: U 93". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 14 December 2014.
- Helgason, Guðmundur. "Ships hit by U 93". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 14 December 2014.
- 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.