HMS Upholder (P37) was a 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...

 U-class

British U class submarine

The British U class submarines were a class of 49 small submarines built just before and during the Second World War...

 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 Vickers-Armstrong

Vickers

Vickers was a famous name in British engineering that existed through many companies from 1828 until 1999.-Early history:Vickers was formed in Sheffield as a steel foundry by the miller Edward Vickers and his father-in-law George Naylor in 1828. Naylor was a partner in the foundry Naylor &...

 at Barrow-in-Furness

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...

. She was laid down on 30 October 1939, launched

Ship naming and launching

The ceremonies involved in naming and launching naval ships are based in traditions thousands of years old.-Methods of launch:There are three principal methods of conveying a new ship from building site to water, only two of which are called "launching." The oldest, most familiar, and most widely...

 on 8 July 1940 by Mrs. Doris Thompson, wife of a director of the builders. The submarine was commissioned

Ship commissioning

Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...

 on 31 October 1940. She was one of four U-class submarines which had two external torpedo

Torpedo

The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

 tubes at the bows in addition to the 4 internal ones fitted to all boats. They were excluded from the other boats because they interfered with depth-keeping at periscope depth.

Career

She was commanded for her entire career by lieutenant-commander Malcolm David Wanklyn

Malcolm David Wanklyn

Lieutenant Commander Malcolm David Wanklyn VC, DSO & Two Bars was the Allies' most successful submariner in the Second World War in terms of tonnage sunk, and received the Victoria Cross, the highest and most prestigious award for gallantry in the face of the enemy that can be awarded to British...

, and became the most successful British submarine of the Second World War. After a working up period, she left for Malta

Malta

Malta , officially known as the Republic of Malta , is a Southern European country consisting of an archipelago situated in the centre of the Mediterranean, south of Sicily, east of Tunisia and north of Libya, with Gibraltar to the west and Alexandria to the east.Malta covers just over in...

 on 10 December 1940 and was attached to the 10th Submarine Flotilla based there. She completed 24 patrols, sinking around 120,000 tons of enemy shipping including the destroyer Libeccio

Maestrale class destroyer

The Maestrale class were a group of destroyers built for the Italian Navy and served in World War II. They were an enlarged version of the Dardo class destroyers. They were 10 m longer and introduced new pattern 120 mm guns...

 after the Battle of the Duisburg Convoy

Battle of the Duisburg Convoy

The Battle of the Duisburg Convoy was fought on the night of 8–9 November 1941 between an Italian convoy sailing to Libya with supplies for the Italian Army, civilian authorities in Libya, and the Afrika Corps and a British Naval squadron which intercepted it...

, a cruiser

Cruiser

A cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...

, three 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...

s (among which the Italian submarine Saint Bon), three troop transports, ten cargo ships, two tankers and a trawler. Wanklyn was awarded the Victoria Cross

Victoria Cross

The Victoria Cross is the highest military decoration awarded for valour "in the face of the enemy" to members of the armed forces of various Commonwealth countries, and previous British Empire territories....

 for a patrol in her in 1941 when he attacked a particularly well defended convoy and sank the 18,000 ton Italian liner SS Conte Rosso

SS Conte Rosso

SS Conte Rosso was an Italian ocean liner active in the early 20th century.Named after Amadeus VII, Count of Savoy, the so-called "Red Count", the Conte Rosso was noted for her lavish Italian interior decoration. Because much of its sailing would be in warmer waters, the designers included an...

. She also damaged the Italian cruiser Giuseppe Garibaldi.

Sinking

Upholder was lost with all hands on her 25th patrol, which was to have been her last before she returned to England. She left for patrol on 6 April 1942 and became overdue on 14 April. On 12 April she was ordered, with HMS Urge

HMS Urge (N17)

HMS Urge was a British U class submarine, of the second group of that class, built by Vickers Armstrong, Barrow-in-Furness. She was laid down on 30 October 1939 and was commissioned on 12 December 1940...

 and HMS Thrasher

HMS Thrasher (N37)

HMS Thrasher was a T-class submarine of the Royal Navy. She was laid down by Cammell Laird & Co Limited, Birkenhead, launched in November 1940, and had an active career in the Mediterranean and Pacific Far East.-Mediterranean:...

 to form a patrol line to intercept a convoy, although it is not known whether she received the signal.

Theories about her loss

The most likely explanation for her loss is that after being spotted by a reconnaissance seaplane

Seaplane

A seaplane is a fixed-wing aircraft capable of taking off and landing on water. Seaplanes that can also take off and land on airfields are a subclass called amphibian aircraft...

, she fell victim to depth charge

Depth charge

A depth charge is an anti-submarine warfare weapon intended to destroy or cripple a target submarine by the shock of exploding near it. Most use explosives and a fuze set to go off at a preselected depth in the ocean. Depth charges can be dropped by either surface ships, patrol aircraft, or from...

s dropped by the Italian Orsa-class torpedo boat

Orsa class torpedo boat

The Orsa class were a group of large torpedo boats or destroyer escorts built for the Italian Navy in the late 1930s. They were an enlarged version of the , with more endurance and a greater depth charge load but less powerful machinery and a lighter gun armament. The surviving pair were rebuilt as...

 Pegaso northeast of Tripoli on 14 April 1942 in the position 34°47′N 15°55′E, although no debris was seen on the surface. The attack was 100 miles northeast from Wanklyn's patrol area and he may have changed position to find more targets. It is also possible that the submarine was sunk by a mine on 11 April 1942 near Tripoli, when a submarine was reported close to a minefield. A third and less-likely theory came from an alleged air and surface attack on a submarine contact by German aircraft and the escort of a convoy on 14 April off Misrata, but no official Axis record of this action was found after the end of World War II.

A more recent research carried out by Italian naval specialist Francesco Mattesini points out to a German aerial patrol supporting the same convoy, composed of two Do 17 and two Bf 110, which attacked an underwater contact with bombs two hours before the Pegaso incident. The author also asserts that the seaplane crew was unsure if the target they pinpointed to Pegaso was a submarine or a school of dolphins. Mattesi, however, admits the possibility that Pegaso could have finished off the submarine previously damaged by the German aircraft.