大象传媒

This account was given by George Cuddon, and is published here with his permission.

"I joined the Navy as a Seaman Boy in January 1941, leaving in April 1954. I served continuously in Terrapin, from her first commissioning in December 1943 until she was finally paid off for scrap in November 1945.

Since this account includes technical terms, the following may provide some clarification, with specific reference to a wartime T boat.

The boat had trimming tanks inside the pressure hull: A tank forward, O tank amidships and Z tank aft, between which water could be transfered to render the boat level, and which could be flooded or pumped out to render the boat neutrally buoyant at a given operating depth. Main ballast tanks outside the pressure hull were open at their bottoms and closed at the tops by hydraulically operated vents. With the vents open water flooded the tanks and the boat dived. With the vents shut, high pressure air could be blown into the main ballast tanks, forcing water out through the open bottoms, surfacing the boat. There was an additional internal Q tank which could be flooded to make the boat extra heavy for quick diving, but which needed to blown out as soon as the boat was well on its way down.

T boats had six external main ballast tanks: No. 1 right forward and Nos 2,3,4,5 and 6 in pairs on either side down the length of the boat. Later T boats, including Terrapin, had 3 and 5 tanks on each side blanked off to act as additional fuel tanks, so that 3 and 5 tanks could not be blown to obtain extra buoyancy.

HMS Terrapin

Terrapin was built at Barrow in Furness and was commissioned at the end of December 1943. Her first CO was Lt Cdr D.S.R. Martin, DSO* who had sunk two German U-boats in the Bay of Biscay while in command of his previous boat, Tuna. He was invalided off the boat after Terrapin's first Far East patrol, suffering from active TB. He died of it in 1947.

Terrapincarried out war patrols in the Skaggerak, between Norway and Denmark, based at the Holy Loch, on the Clyde. Later she did war patrols in the Strait of Malacca and Gulf of Martaban, based at Trincomalee, Sri Lanka. At the end of March 1945, Terrapin moved to Fremantle, Western Australia to join US submarines operating up into the Pacific. Up to this time Terrapin had sunk the German ships Werth and Schwabenland, totalling 18000 tons, a Japanese Kosentai class minelayer and a Hashidate class frigate, all by torpedo, together with twelve ships sunk by gun action and six ships boarded and sunk by demolition charges.

Terrapin left Fremantle for what proved to be her final war patrol on 20 April 1945 and passed northward through the Lombok Strait, between Bali and Lombok, on the surface and at maximum speed, after dark on 27 April. The Japanese maintained quite intensive patrols in the Strait, from their base at Lembar on Lombok, since it was known to be the route by which submarines from Fremantle entered the Java Sea and, in the case of the US boats, the South China Sea. Unlike the US boats, British boats did not have sufficent range to operate from Fremantle into the South China Sea. After clearing the Lombok Strait Terrapin was twice attacked by aircraft which dropped bombs and depth charges. During the following three weeks Terrapin sank five vessels either by gun action or boarding and sinking, in each case the crews took to the boats which were in sight of land.

Early in the afternoon of 19 May, close inshore just east of Jakarta, Terrapin attacked a small tanker accompanied by two escorts, firing her three stern torpedoes. The sea was glassy calm and the periscope or the torpedo tracks were probably observed, since the target was seen to turn away. One explosion was heard immediately after the estimated running time of the third orpedo. The escorts turned towards and came at high speed down the torpedo tracks. The estimated depth of water on the chart was 150 feet and Terrapin attempted to go to 100 feet, but hit the bottom where there proved to be only 57 feet of water. Her screws could be heard thrashing the silt loudly and the motors were stopped.

The escorts could be heard closing fast and five charges were dropped, very close. All the lights went out and the sonar stopped training. Five more charges, even closer, were dropped and 40 feet of the hull on the port side forward buckled in to a distance of 15 inches. There was considerable leakage into the torpedo tube space, where rivets had been displaced inwards on the port side. The forward part of the main pumping and flooding line was crushed. The tube space was evacuated and its watertight doors shut. Leaks occurred in the forward auxiliary machinery space and in the control room, fan jets of water spraying inwards. Blue flashes and loud thumps were heard as seawater contacted electrical equipment. Emergency battery lamps were rigged up and oilskins were placed to direct the sprays away from the batteries and into the bilges. Several fires, including those in both AC generators, were started. The fires were fairly quickly extinguished, but diminished the finite supply of oxygen. The cases of both underwater signal guns were cracked and leaking. Q tank (the quick flooding tank for rapid descent) and A tank (the forward internal trimming tank) were flooded. Both periscopes were flooded, with water squirting from the eyepieces. With all machinery, including ventilation, shut off the temperature in the boat went above 40oC.

There were several more crossing runs, accompanied by depth charges, two of them very close. After ahout two hours there were several crossing runs which were not accompanied by explosions. Two possibilities were considered: either the escorts were out of depth charges, or that they had lost our position. However, on the next crossing run a charge was heard to hit Terrapin and slide down the hull, presumably to rest on the bottom, its depth apparently being overset. The thought occurred that since it was pressure-responsive, another depth charge might trigger it. There was also the possibility that the earlier crossing runs without explosions might in fact have surrounded Terrapin with several charges, all waiting to explode. This was not a comfortable thought.

An attempt was made to release Terrapin from the bottom, so as to move away from a possible depth charge 'nest'. Nos 1, 2 and 6 main ballast tanks were partially blown, together with A and Q tanks. The motors were run half astern. The screws made a huge amount of noise and were stopped. Air could be heard leaking from the vent of 1 main ballast tank, at least. The attempt to move the boat was abandoned. The noise of the screws, as well as the large amount of air from 1 main ballast tank seemed to give the escorts something to aim at, because there were other crossing runs with close charges which did not, however, add significantly to the damage already suffered, though the knowledge that a depth charge lay close alongside caused us to be even more teeth-grittingly apprehensive.

Though every crew member must have been in the same state of terror as myself, no one said a word. We all played at being hard men, and the unforgivable thing was to show, or admit to, fear. 'Hard man' in those days did not mean what it appears to mean today, when it seems to mean throwing one's weight about and punching people in the face. Then it meant indifference, real or pretended (mostly I think the latter) to hardship and danger.

After dark at about 1900 Terrapin attempted to surface. It was by no means certain that we would be able to do so, in view of the flooding of the tube space, 1 main ballast tank and A tank. Numbers 2, 4 and 6 main ballast tanks were blown and the stern came unstuck, leaving us with a steep bow down angle. It was not initially possible to tell whether we were, in fact, surfacing, since all depth gauges were smashed. The sound of the sea splashing against our hull suggested we were, at least partly, on the surface, though very much bow down, and the skipper cautiously opened the upper conning tower hatch. The gun's crew clambered out to man the gun, though that would have availed us little if the escorts had seen us.

There was no question of surrender, we were aware of the treatment we could expect as prisoners of the Japanese. A first-quarter moon was setting in the northwest and the enemy were sighted up-moon of Terrapin, who turned stern on and moved out. The enemy gave no sign that they had seen Terrapin, who worked her way round to the north west with the intention of lying bottomed near the Thousand Islands, west of Jakarta, during the next day, and leaving the Java Sea by way of the Sunda Strait that night. That move was forestalled by the appearance of two ships apparently Japanese warships, to the westward, and Terrapin altered course to the north east with the intention of exitting the Java Sea by way of the Lombok Strait.

The air activity observed in the Lombok area when outward bound to the patrol area meant that Terrapin would be likely to have to dive. At dawn on 20 May Terrapin dived to attempt to obtain a trim. This was complicated by the fact that the fore planes were jammed and would move only very slowly in response to the controls. They could not be turned in. One guntower hatch was found to be leaking badly. Terrapin surfaced and this hatch was tightened down, to an extent which would probably make it difficult to open.

Terrapin dived again and was found to be very heavy amidships and forward. The boat porpoised up and down quite steeply as a result of the extreme stiffness of the fore planes. It was nevertheless possible to hold the boat with the fore planes amidships, by partially blowing main ballast, though she could not be allowed to go deep because of the leaks, particularly in the tube space. On that basis Terrapin made for the Lombok Strait, keeping well away from the Java coast. The fact that both W/T alternators were burnt out and the Type 55 transmitter was inoperable meant that Terrapin could not transmit by radio. The 291 radar was still working since it was powered by a small, very noisy, alternator sited below the set in the W/T office. Several times aircraft were detected and each time Terrapin stopped, on the basis that the most conspicuous thing about her was her wake.

Just after dawn on 23 May the US submarine Cavalla was sighted and Terrapin's predicament explained to her. Cavalla signalled her intention of staying on the surface to stand by Terrapin and escort her out through the Lombok Strait. Cavalla also transmitted a signal from Terrapin to CO Task Force 71 explaining the situation. Cavalla, who had been nearly two months at sea, signalled, 'Do any of your crew wish to come aboard for a bath and a rest,' indicative of the fact that US submarines, who could distill 2000 gallons per day, had no water shortage. Terrapin's CO declined, saying that morale was 100 percent.

Terrapin's water situation was grim. The shaking had stirred up the 18 months of sediment in the fresh water tanks and what came out of the taps was cloudy and coloured a greenish yellow. Oil had got into everything and every drink of tea had rainbow rings on its surface. The seamen's mess locker had sheared its mounts and crashed down into the forward auxiliary machinery space below the deck, breaking all but a few of the crocks. Most of the cutlery was in the bilges. The seamen's mess mostly ate directly from the cooking dishes. There were insufficient intact light bulbs left to replace all of those smashed during the depth charging, so the crew had to grope about in the gloom, particularly in the accommodation space.

Just after midnight on 22 May, Cavalla and Terrapin entered the Lombok Strait, where the strong southerly current aided Terrapinto make about 12 knots over the ground and by 0400 she had cleared the southern entrance. Terrapin's crew all felt they were off the hook, though it was necessary to keep a sharp radar and visual look-out for aircraft for another 24 hours.

In the evening of 30 May Terrapin entered Fremantle harbour. Examination showed that, in addition to the hull collapse, the forward torpedo tubes were distorted and out of line. The boat had, in effect, become slightly banana-shaped. She was classed as Total Constructional Loss, fit only for scrap. Fortunately the builders, Vickers, were anxious to study the effect of close depth charging on a rivetted hull and it was decided to send her home. She was patched up for a passage on the surface and left Fremantle at the beginning of August 1945, arriving at Gosport in October. She was subsequently towed to Troon for breaking up."

Glossary

Fore ends: the torpedo tube space and the torpedo stowage compartment immediately aft of it. These two compartments were separated by a bulkhead having watertight doors.

AMS: auxiliary machinery space below the main deck. It contained the pump for transfering water between, or from, the A, O and Z trimming tanks.

Guntower: a tower forward of the conning tower, for rapid access to the 4" gun. It had two upper hatches to enable the gun's crew to get out quickly. Note that the conning tower is, properly speaking, the tube which extends between the control room and the bridge. The bridge is ofter erroneously referred to by laymen as the conning tower.

Planes: the fore and after hydroplanes which acted like horizontal rudders to control the boat when dived (assuming that the trim was nearly correct). The fore planes could be turned in when on the surface.

W/T alternator: alternators that converted the boat's battery DC supply to AC, mainly for use by the radio equipment.

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