SM UB-115

SM UB-115 was a German Type UB III submarine or U-boat in the German Imperial Navy (Kaiserliche Marine) during World War I. She was commissioned into the German Imperial Navy on 28 May 1918 as SM UB-115. She was the only German submarine commissioned with the number 115.

UB-115 was sunk by British warships, including HMS Ouse and HMS Star, and the rigid airship R29 at 55.21667°N, -1.36667°W using depth charges and aerial bombs.

Construction
She was built by Blohm & Voss of Hamburg and following just under a year of construction, launched at Hamburg on 4 November 1917. UB-115 was commissioned in the spring the next year under the command of Oblt.z.S. Reinhold Thomsen. Like all Type UB III submarines, UB-115 carried 10 torpedoes and was armed with a 8.8 cm deck gun. UB-115 would carry a crew of up to 3 officers and 31 men and had a cruising range of 7420 nmi. UB-115 had a displacement of 519 t while surfaced and 649 t when submerged. Her engines enabled her to travel at 13.3 kn when surfaced and 7.4 kn when submerged.

Fate
On 29 September 1918 while under the command of Reinhold Thomsen, UB-115 was engaged by armed trawlers (amongst others Viola), the airship R29, HMS Ouse and HMS Star (1896). UB-115 was depth charged until destroyed and went down at position 55.24611°N, -1.37917°W (WGS84), about 4.5 nmi northeast of Beacon Point, Newton-by-the-Sea, off Northumberland. All 39 men aboard the submarine died in the attack and sinking.

UB-115's wreck lies in two pieces and is covered in soft corals and an accretion formed from fly ash from a local power plant.