HMS Thistle (N24) was a T-class

British T class submarine

The Royal Navy's T class of diesel-electric submarines was designed in the 1930s to replace the O, P and R classes. Fifty-three members of the class were built just before and during the Second World War, where they played a major role in the Royal Navy's submarine operations...

 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...

 of the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

. She was laid down by Vickers Armstrong

Vickers Armstrong

Vickers-Armstrongs Limited was a British engineering conglomerate formed by the merger of the assets of Vickers Limited and Sir W G Armstrong Whitworth & Company in 1927...

, Barrow

Barrow-in-Furness

Barrow-in-Furness is an industrial town and seaport which forms about half the territory of the wider Borough of Barrow-in-Furness in the county of Cumbria, England. It lies north of Liverpool, northwest of Manchester and southwest from the county town of Carlisle...

 and launched in October 1939.

Career

Thistle had a short wartime career with the Royal Navy.

Thistle was ordered to patrol off Stavanger

Stavanger

Stavanger is a city and municipality in the county of Rogaland, Norway.Stavanger municipality has a population of 126,469. There are 197,852 people living in the Stavanger conurbation, making Stavanger the fourth largest city, but the third largest urban area, in Norway...

, and to sink any enemy vessel that she might spot in the harbour, since the authorities believed that a German invasion of Norway

Operation Weserübung

Operation Weserübung was the code name for Germany's assault on Denmark and Norway during the Second World War and the opening operation of the Norwegian Campaign...

 was imminent. On 10 April Thistle signalled her intention to comply with this order and that she had two torpedoes remaining after an unsuccessful attack on a U-boat

U-boat

U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...

. With this in mind the Admiralty changed her orders to patrol off Skudenes. No further contact was made with Thistle. It was later discovered that , the U-boat Thistle had previously attacked, had sighted the submarine on the surface and sunk her with torpedoes.