Trenchant is an ethos and a namesake with rich history:
The first HMS Trenchant was a 1085 ton modified ‘R’ class destroyer built in 1916 and saw service with the 15th Destroyer Flotilla of the Grand Fleet during the Great war before being de-commissioned and taken to Faslane to be broken up in 1928.
The second vessel to bear the name ‘Trenchant’ was a ‘T’ class diesel submarine built at Chatham Dockyard in 1943. Before she completed construction, ‘Trenchant’ was assigned the then crew of HM/SM Thrasher when the latter was taken in for refit. This included one Lieutenant Commander A R Hezlet who became the youngest commanding officer in the RN at that time.
On the 23rd of September 1944 Trenchant sighted the German submarine U859 running on the surface off Penang, Trenchant attacked with three stern torpedoes one of which hit below the conning tower, sending the German submarine to the bottom. After U859 sank Trenchant surfaced and recovered 17 survivors of U859’s crew including her captain and transported them as POW’s to Trincomalee, U859’s CO Kapitanleutnant Johann Jebson congratulated Cmdr Hezlet and Trenchant’s crew on the sinking of his U-boat.
Trenchant continued in her task of seeking out and sinking enemy shipping throughout the rest of 1944 and early 1945. Her biggest success however came on the 7th June 1945 when Trenchant was on patrol off the Banka strait when a communication was received from a US submarine that they had sighted a Japanese cruiser in Trenchant’s vicinity escorted by a destroyer. Cmdr Hezlet calculated the course that the enemy warships would use and set a course to intercept them. His calculations turned out to be correct. The warships were sighted just over a mile off shore. This area was assigned to the US Navy and Cmdr Hezlet therefore had to ask permission to engage the cruiser from Rear-Admiral R A J Fife USN. This was granted and an interception successfully achieved. The cruiser was the Japanese Nachi class heavy cruiser ‘Ashigara’.
As it was night Trenchant was running on the surface to recharge her batteries, it was while on the surface that the Ashigara’s escort destroyer was first sighted. Trenchant remained on the surface as Cmdr Hezlet did not want to risk losing contact by submerging. The Japanese destroyer however sighted the Trenchant and proceeded to open fire on her at little more than point blank range. Trenchant returned fire with one torpedo. This missed but Trenchant did succeed in evading the destroyer.
Trenchant finally submerged at dawn and proceeded to lay in wait for the Ashigara. The escort destroyer continued its search for Trenchant and the Ashigara followed after a short interval. Trenchant manoeuvred as close as possible in order to affect the best firing solution. When this was done she fired all eight of her bow torpedoes. Cmdr Hezlet then downed the periscope and waited for the torpedoes to hit. The Ashigara was about two miles away when the torpedoes were fired and this was the limit of their range. After three minutes Cmdr Hezlet put up the periscope again just in time to see five torpedoes strike the Ashigara sending columns of water higher than her mainmast.
After this the Ashigara was obscured by smoke, making it impossible to carry out a damage assessment for some minutes. When she became visible again it was possible to see she was stopped dead in the water and on fire with a heavy list, some of her crew already abandoning ship.
The Ashigara had been built with a triple hull and the Japanese were confident that this gave her the greatest possible protection against torpedo attack.
Nonetheless Trenchant’s torpedoes blew a portion of her bows clean off. This caused part of her upper structure to fall into the sea. Cmdr Hezlet proceeded to manoeuvre Trenchant to bring his stern torpedo tubes to bear on the stricken cruiser. It was during this time that Cmdr Hezlet decided to let over 30 of the ship’s company look through the periscope at the sinking cruiser. The crew of the Ashigara however sighted Trenchant’s periscope and opened fire with an anti-aircraft gun. Cmdr Hezlet took control of the periscope again (after a lengthy wait in the queue) and upon doing so sighted the escort destroyer approaching him high speed. Trenchant withdrew to deeper water and successfully evaded the destroyer. The Ashigara sank 30 minutes later.
The sinking of the Ashigara earned Cmdr Hezlet a congratulatory signal from flag officer submarines, Admiral Barry. He was also awarded a second DSM and the US Legion of Merit, the highest honour the US can bestow upon a foreign commander, this was presented by Rear-Admiral A. J. Fife at Subic Bay in the Philippines. Trenchant’s attack on the Ashigara was later described as one of the most brilliant attacks of the war earning Trenchant the battle honour Malaya 1944-45.
The Ashigara was the last major warship to be sunk by a British submarine until the Argentine cruiser ‘General Belgrano’ was sunk by HM/SM Conquerer during the Falklands Campaign in 1982.
Trenchant Returned to the UK in July 1945 and continued to serve with distinction until 1963 when she was finally paid off and taken to Faslane on the 23rd of July and broken up for scrap.
The Present HMS Trenchant is the fifth of the Trafalgar Class Nuclear powered Submarines currently in service, launched by Lady Hunt wife of Admiral Sir Nicholas Hunt the then Commander in Chief Fleet on the 3rd of November 1986 at the VSEL dockyard in Barrow-in-Furness. Also present at the launching was one Vice Admiral Sir Arthur Hezlet KBE CB DSO and Bar DSC.
Weighing in at an impressive 5200 tons she is certainly larger than her predecessors but combined with her Nuclear power plant and her weapons fit she is by far a more potent force than the previous Trenchant’s crew could have possibly dreamed of. Indeed Trenchant is only restricted by the amount of food that can be carried for the ship’s company.
Now that she has completed her refit, Trenchant is capable of fulfilling any role assigned to her. Fitted with the Royal Navy’s most advanced sonar suite in the 2076 sonar arrays, Trenchant has the ability to gather enormous quantities of information from her environment enabling her to detect and track surface and sub-surface vessels without them being aware that they are being scrutinized from below.
It is war however that Trenchant is designed for and after her refit is more than capable to respond to any threat posed in the present day world scene. Armed with wire-guided Spearfish torpedoes and Sub-Harpoon anti-ship missiles she can deal with any threat on the ocean. Now with the fitting of Tomahawk cruise missiles she can influence events far inland as has been shown by the events in the former Yugoslavia and more recently in the actions taken against Afghanistan in the war against terror.
In short, HMS Trenchant is now even better equipped to continue the finest traditions of the Submarine Service of being the silent masters of the deep.