Large Patrol Submarine


T Class

Third Group

Pennant No.:
P.311 - Renumbered July 1941.
Was to have been renamed Tutankhamen.
P.91 - Laid down as P.91.

Laid Down:
25th April 1941.
Vickers, Barrow-in-Furness.

7th August 1942.
Cdr. R. Cayley.

June 1942 - Jan. 1943
Cdr. R. Cayley.

5 Officers and 58 Ratings (normally).

Service Career:
1942 - 1st Flotilla.
HMS Medway, Alexandria.

P.311 along with Trooper and Thunderbolt were converted to carry 2-man torpedoes (chariots) on their casing for 'Operation Principle.
This operation involved Trooper and Thunderbolt attacking Palermo and Cagliari harbours respectively. P.311 was to attack the harbour of Maddelena.
She departed Malta on 28th December 1942, her position was reported in the early hours of the 31st December she was not heard from again.
It is assumed that she was mined off Maddelena which was heavily mined.

Lost, presumed mined off Maddelena on or about 2nd January 1943.

It should be noted that boats attached to 1st Flotilla in Alexandria were likely to spend much of their time at Malta even though Malta had been given up as a submarine base due to the air attacks. Although submarines did still operate from Malta during this period the 10th Flotilla was not recognised as such until September 1941.