HM SM P.311, reporting from patrol
The British completed 53 T-class (Triton) submarines in the 1930s and 40s and these 276-foot vessels took the war to the enemies of the crown and we have covered at least one of these boats, HMS Tribune (aka HMS Tyrant) in a past Warship Wednesday.
These sea monsters, designed in 1935, had an impressive armament of 10 torpedo tubes (6 bow, 4 aft) which was considered devastating at the time, room for 16 torpedoes, and mounted a QF 4-incher on deck. A crew of 48 manned the 1,500-ton smoke boat and twin diesel/electric engines/motors could drive them at nearly 16 knots on the surface and 9 when submerged. They weren’t flashy compared to the German, U.S. and Japanese fleet boats of the day, but they could sail 8,000 nautical miles and could operate at a 300 foot depth with no problem.
Nearly one in three T-class boats did not survive the war, with 16 destroyed, largely by mines and in scraps with Italian and German subs in the Med.
Which brings us to His Majesty’s Submarine P.311
Commissioned 7 Aug 1942, she was the only unnamed T-class boat, the late series Group Three boat would have been dubbed Tutenkhamen but lost just over four months later before she could be renamed.
Here is one of the few photographs in circulation of her:
Fitted to carry 2 Chariot human torpedoes, she along with sisters Thunderbolt and Trooper and U-class sub HMS Unruffled (P 46) were part of Operation Principle, the Chariot attack on Italian cruisers at La Maddalena (Palermo).
HMS P 311 departed from Malta on 28 December 1942, sending her last signal three days later from 38º10’N, 11º30’E.
After this signal she was not heard from again and she is presumed sunk by Italian mines in the approaches to Maddalena on after she was reported overdue and failed to return to base, her 71 crewmen on eternal patrol.
A submarine down, Principal didn’t really go off as planned, but did claim an Italian cruiser and some small craft for the loss of ten highly trained frogmen:
Submarines TROOPER (with Chariots 16, 19, and 23) and THUNDERBOLT (with 15 and 22) launched all five Chariots against Palermo. They then withdrew, leaving submarine P.46 to pick up the crews. The fates of the Chariots follow:
Chariot 16 (Sub Lt R G Dove RNVR and Leading Seaman J Freel) mined liner VIMINALE (8500grt) which was badly damaged.
Chariot 19 (Ty/Lt H F Cook RNVR and Able Seaman Worthy). Lt Cook was drowned when his suit was torn getting through the boom defense nets, but AB Worthy drove the Chariot ashore and blew it up prior to being captured.
Chariot 23 (Sub Lt H L H Stevens RNVR and Leading Seaman Carter) had to abandon the attack due to mechanical failure and her crew was picked up by P.46.
Chariot 15 (Ty/Petty Officer J M Miln and Able Seaman W Simpson) was lost with due to unknown causes prior to entering harbour. AB Simpson was lost, but PO Miln survived.
Chariot 22 (Lt R T G Greenland RNVR and Leading Signalman A Ferrier), was able to mine new light cruiser ULPIO TRAIANO, which was sunk. Mines were also fixed to destroyer GRECALE and corvettes CICLONE and GAMMA, but were removed before exploding.
The crews of Chariot 16 and 22 were also captured.
As for her two mission sisters, Thunderbolt was sunk by the Italian corvette Cicogna off Messina Strait on 14 March 1942 and Trooper was lost, probably to German mines, on 14 October 1943.
Now apparently P.311 has been found
A team led by Genoa-based wreck-hunter, Massimo Domenico Bondone, located the final resting place of the British T-class submarine, the HMS P 311, on 22 May 2016.
The vessel was found at a depth of 100 metres, not far from the island of Tavolara, off the northeast coast of Sardinia.
Paola Pegoraro of the Orso Diving Club, who helped prepare the dive, told the Associated Press the sub was identified by the two Chariot “human torpedoes” still affixed to the outside.
Vale, P.311, rocked in the cradle of the deep.