HMS K12 was a K class

British K class submarine

The K class submarines were a class of steam-propelled submarines of the Royal Navy designed in 1913. Intended as large, fast vessels which had the endurance and speed to operate with the battle fleet, they gained notoriety, and the nickname of Kalamity class, for being involved in many accidents....

 submarine

Submarine

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

 built by Armstrong Whitworth

Armstrong Whitworth

Sir W G Armstrong Whitworth & Co Ltd was a major British manufacturing company of the early years of the 20th century. Headquartered in Elswick, Newcastle upon Tyne, Armstrong Whitworth engaged in the construction of armaments, ships, locomotives, automobiles, and aircraft.-History:In 1847,...

, Newcastle upon Tyne

Newcastle upon Tyne

Newcastle upon Tyne is a city and metropolitan borough of Tyne and Wear, in North East England. Historically a part of Northumberland, it is situated on the north bank of the River Tyne...

. She was laid down in October 1915 and commissioned in August 1917.

K12 took part in the Battle of May Island

Battle of May Island

The Battle of May Island is the name given to the series of accidents that occurred during Operation E.C.1 in 1918.Named after the Isle of May, an island in the Firth of Forth, close by, it was a disastrous series of accidents amongst Royal Navy ships on their way from Rosyth in Scotland to fleet...

, surviving the disastrous exercise. Then in 1924, K12 collided with . K2 smashed a hole in the forward casing of K12 while K2 buckled her bows for about six feet. K12 was scrapped in 1926 in Charlestown.