HMS P311

300px Practise torpedo is loaded onto P311 at Holy Loch, Scotland, 1942
History
Name:	HMS P311
Ordered:	11 June 1931
Builder:	Vickers Armstrong, Barrow
Laid down:	25 April 1941
Launched:	5 March 1942
Commissioned:	7 August 1942
Fate:	sunk 8 January 1943
Badge:	100px
General characteristics
Displacement:	1,290 tons surfaced 1,560 tons submerged
Length:	276 ft 6 in (84.28 m)
Beam:	25 ft 6 in (7.77 m)
Draught:	12 ft 9 in (3.89 m) forward 14 ft 7 in (4.45 m) aft
Propulsion:	Two shafts Twin diesel engines 2,500 hp (1.86 MW) each Twin electric motors 1,450 hp (1.08 MW) each
Speed:	15.5 knots (28.7 km/h) surfaced 9 knots (20 km/h) submerged
Range:	4,500 nautical miles at 11 knots (8,330 km at 20 km/h) surfaced
Test depth:	300 ft (91 m)
Complement:	61
Armament:	6 internal forward-facing torpedo tubes 2 external forward-facing torpedo tubes 2 external amidships rear-facing torpedo tubes 1 external rear-facing torpedo tubes 6 reload torpedoes 4 inch (100 mm) deck gun

HMS P311 was a T-class submarine of the Royal Navy, the only boat of her class never to be given a name. She was to have received the name Tutankhamen but was lost before this was formally done. P311 was a Group 3 T-class boat built by Vickers-Armstrong at Barrow-in-Furness and commissioned on 5 March 1942 under the command of Lieutenant R.D. Cayley. She was one of only two T-class submarines completed without an Oerlikon 20 mm anti-aircraft gun, the other being HMS Trespasser.

Naming

The Prime Minister, Winston Churchill had minuted the Admiralty on 5 November 1942, 19 December and again on 27 December, saying that all submarines should have names. In the final minute, he provided a list of suggestions and insisted that all unnamed submarines be given names within a fortnight. P311 was to be assigned the name Tutankhamen, after the Egyptian king. She would have been the only vessel of the Royal Navy, before or since, to bear the name. She was lost in the Mediterranean between late December 1942 or early January 1943, before the new name could be formally assigned. She therefore never received the name Tutankhamen, and is officially designated as P311.

Career

She joined the 10th Submarine Flotilla at Malta in November 1942, and was lost with all hands between 30 December 1942 and 8 January 1943 whilst en route to La Maddalena, Sardinia where she was to attack two Italian 8-inch gun cruisers using Chariot human torpedoes carried on the casing as part of Operation Principle. She was reported overdue on 8 January 1943 when she failed to return to base. It was assumed that she was mined.