SM UB-40

SM UB-40 was a German Type UB II submarine or U-boat in the German Imperial Navy (Kaiserliche Marine) during World War I.

Design
A Type UB II submarine, UB-40 had a displacement of 274 t when at the surface and 303 t while submerged. She had a total length of 36.90 m, a beam of 4.37 m, and a draught of 3.69 m. The submarine was powered by two Körting six-cylinder diesel engines producing a total 284 PS, two Siemens-Schuckert electric motors producing 280 PS, and one propeller shaft. She was capable of operating at depths of up to 50 m.

The submarine had a maximum surface speed of 9.15 kn and a maximum submerged speed of 5.81 kn. When submerged, she could operate for 45 nmi at 4 kn; when surfaced, she could travel 6450 nmi at 5 kn. UB-40 was fitted with two 50 cm torpedo tubes, four torpedoes, and one 8.8 cm Uk L/30 deck gun. She had a complement of twenty-one crew members and two officers and a 42-second dive time.

Construction and career
The U-boat was ordered on 22 July 1915 and launched on 25 April 1916. She was commissioned into the German Imperial Navy on 17 August 1916 as SM UB-40.

The submarine sank 100 ships in 28 patrols. UB-40 was scuttled in Ostend when the German army retreated from Belgium on 5 October 1918.

The wreck of UB-40 has been located & identified by divers in the recent years.