AndPossiblyCaptionHere
	Career
Ordered:
Laid down:
Launched:	September 1944
Commissioned:
Decommissioned:
Fate:	wrecked by own torpedo explosion, refloated, sunk as a target 14 June 1957
Stricken:
General Characteristics
Displacement:	814-872 tons surfaced, 990 submerged
Length:	217 feet (66 m)
Beam:	23.5 feet (7.1 m)
Draught:	11 feet (3.3 m)
Propulsion:
Speed:	14.75 knots (27 km/h) surfaced, 8 knots (15 km/h) submerged
Range:
Complement:	48 officers and men
Armament:	one three-inch (76 mm) gun, one 20 mm antiaircraft gun; three .303 machine (~7.7 mm) guns, seven 21-inch (533 mm) torpedo tubes, six forward, one aft, 13 torpedoes
Motto:

HMS Sidon was launched in September 1944, one of the third group of S-class submarines built by Cammell Laird & Co Limited, Birkenhead. This image is a temporary placeholder for articles(mostly those utilizing the table from Wikipedia:WikiProject Ships/Tables) which still need a picture to illustrate them. ... The source for an SVG image of the White Ensign can be found at User:David Newton/SVG Graphics/White Ensign. ... 1944 was a leap year starting on Saturday (link will take you to calendar). ... June 14 is the 165th day of the year in the Gregorian calendar (166th in leap years), with 200 days remaining. ... 1957 was a common year starting on Tuesday of the Gregorian calendar. ... 1944 was a leap year starting on Saturday (link will take you to calendar). ... The S-class submarines of the Royal Navy were designed and built during the modernisation of the submarine force in the early 1930s to meet the need for smaller boats to patrol the restricted waters of the North Sea and the Mediterranean Sea. ... Cammell Laird, one of the most famous names in British shipbuilding during the nineteenth and twentieth centuries, came about following the merger of Laird, Son & Co. ... Map sources for Birkenhead at grid reference SJ3088 Birkenhead is a town on The Wirral Peninsula, Merseyside, on the left bank of the River Mersey, opposite Liverpool. ...

On the morning of June 16, 1955, Sidon was moored alongside the depot ship HMS Maidstone in Portland Harbour. Two experimental torpedoes, code-named "Fancy," had been loaded aboard for testing. Fifty-six officers and crewmen were aboard. June 16 is the 167th day of the year in the Gregorian calendar (168th in leap years), with 198 days remaining. ... 1955 is a common year starting on Saturday of the Gregorian calendar. ... A submarine depot ship of the Royal Navy. ... Two RIBs at Castletown, Portland Harbour Portland Harbour is located beside the Isle of Portland, off Dorset, on the south coast of England. ... A modern torpedo, historically called a self propelled torpedo, is a self-propelled guided projectile that (after being launched above or below the water surface) operates underwater and is designed to detonate on contact or in proximity to a target. ...

At 08:25, an explosion in one of the Fancy torpedoes (but not the warhead) burst the number-three torpedo tube it was loaded into and ruptured the forward-most two watertight bulkheads. Fire, toxic gases, and smoke accompanied the blast. Twelve men in the forward compartments died quickly and seven others were seriously injured.

The submarine started to settle by the bows with a list to starboard, and her commanding officer, Lieutenant Commander Verry, ordered the ship evacuated from the engine room and after escape hatches. Thanks to a rescue party from Maidstone, everyone not immediately killed escaped, except Maidstone's medical officer. He had gone aboard with the rescue party, assisted several survivors, and collapsed, unnoticed, in the control room after everyone else had left. At about 08:50 Sidon sank to the bottom of the harbour.

One week later the wreck was raised and towed into a causeway on Chesil Beach. The bodies of the 13 casualties were removed and buried with full honours in the Portland Naval Cemetery on top of the cliffs overlooking the harbour. A Court of Inquiry cleared anyone aboard Sidon for the loss of the boat. The direct cause of the accident was determined to have been malfunctioning of the "Fancy" torpedo, and that torpedo program was terminated.

A torpedo being readied for the morning test shot had begun a "hot-run" — its engine had started while it was still inside the submarine and was over-speeding, creating very high pressures in its fuel system. The "Fancy" torpedo used "High Test Peroxide" (HTP) as an oxidizer. When an oxidizer line burst, HTP sprayed onto the copper fittings inside the torpedo, decomposing into oxygen and steam. The torpedo's warhead did not detonate, but its hull burst violently, rupturing the torpedo tube and causing the flooding that destroyed the boat. Hydrogen peroxide (H2O2) is a clear liquid, slightly more viscous than water, that has strong oxidizing properties and is therefore a powerful bleaching agent that has found use as a disinfectant and (in high concentrations as high test peroxide) as an oxidizer or monopropellant in rockets. ...

Sidon was refloated, and sunk as an ASDIC target on June 14, 1957. The F70 type frigates (here, Motte-Picquet) are fitted with VDS (Variable Depth Sonar) type DUBV43 or DUBV43C tugged sonars Sonar (sound navigation and ranging) is a technique that uses sound propagation under water to navigate or to detect other watercraft. ... June 14 is the 165th day of the year in the Gregorian calendar (166th in leap years), with 200 days remaining. ... 1957 was a common year starting on Tuesday of the Gregorian calendar. ...

See also

• See HMS Sidon for other ships of this name.
• Submarines destroyed by hotrunning torpedoes: HMS Sidon (P259) – USS Scorpion (SSN-589) – Russian submarine Kursk