HMS Umpire (N82) 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 at Chatham Dockyard

Chatham Dockyard

Chatham Dockyard, located on the River Medway and of which two-thirds is in Gillingham and one third in Chatham, Kent, England, came into existence at the time when, following the Reformation, relations with the Catholic countries of Europe had worsened, leading to a requirement for additional...

 and sunk in an accident nine days after commissioning with the loss of 22 men.
The submarine was sunk whilst en-route from Chatham to join the 3rd Submarine Flotilla at Dunoon

Dunoon

Dunoon is a resort town situated on the Cowal Peninsula in Argyll, Scotland. It sits on the Firth of Clyde to the south of Holy Loch and to the west of Gourock.-Waterfront:...

, under the command of Lieutenant Mervyn Wingfield. From Dunoon she was to carry out a single working-up patrol in the North Sea before heading to the Mediterranean. She stopped overnight at Sheerness

Sheerness

Sheerness is a town located beside the mouth of the River Medway on the northwest corner of the Isle of Sheppey in north Kent, England. With a population of 12,000 it is the largest town on the island....

 and joined a convoy headed North. The submarine suffered engine failure with one of the two diesel engines and as a result fell behind the convoy; the propellers were driven purely by electric motors on the surface and when submerged with no mechanical linkage to the diesel engines. The convoy passed a Southbound convoy around midnight whilst about 12 nautical miles (22 km) off Blakeney, Norfolk

Blakeney, Norfolk

Blakeney is a coastal village and civil parish in the English county of Norfolk. Blakeney lies within the Norfolk Coast AONB and the North Norfolk Heritage Coast. The North Norfolk Coastal Path passes through the village...

, with the two convoys passing starboard to starboard; this was unusual since ships and convoys should pass port to port. No ships showed any lights because of the risk from German E-boat

E-boat

E-boats was the designation for Motor Torpedo Boats of the German Navy during World War II. It is commonly held that the E stood for Enemy....

s. However, an armed escort trawler, Peter Hendriks in the southbound convoy accidentally struck Umpire sinking her in 18 metres of water.

Four crew members were on the bridge when the submarine sank - Wingfield, the navigator and two lookouts. However only Wingfield survived in the cold water to be picked up by the trawler. Several other personnel also survived, escaping from the sunken wreck using the conning tower or the engine room escape hatch, the majority wearing DSEA. ERA Killen received a British Empire Medal

British Empire Medal

The Medal of the Order of the British Empire for Meritorious Service, usually known as the British Empire Medal , is a British medal awarded for meritorious civil or military service worthy of recognition by the Crown...

 for leaving the submarine wearing DSEA to check for obstructions around the engine room hatch and then returning to the engine room to assist the other crew members in escaping. He remained in the engine room until everyone else there had escaped. 16 of the crew successfully escaped, 22 crew were lost.

The wreck is designated as a protected place under the Protection of Military Remains Act 1986

Protection of Military Remains Act 1986

The Protection of Military Remains Act 1986 is an Act of Parliament in the United Kingdom which provides protection for the wreckage of military aircraft and designated military vessels. The Act provides for two types of protection: protected places and controlled sites. Military aircraft are...

.