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Trigger I (SS-237)

Image related to Trigger I
Caption: The crew of Trigger (SS-237) celebrate the four torpedo hits which damaged the Japanese carrier Hiyo.

(SS-237: dp. 1,552 (surf.), 2,415 (subm.); 1. 311'8"; b. 27'3"; dr. 15'3"; s. 20.25 k. (surf.), 8.75 k. (subm.); cpl. 80; a. 10 21" tt., 1 3", 2 .50 cal. mg.; cl. Gato)

The triggerfish is any of numerous deep-bodied fishes of warm seas haying an anterior dorsal fin with two or three stout erectile spines.


The first Trigger (SS-237) was laid down on 1 February 1941 at Mare Island, Calif., by the Mare Island Navy Yard; launched on 22 October 1941; sponsored by Mrs. Walter N. Vernou; and commissioned on 30 January 1942, Lt. Comdr. Jack H. Lewis in command.

The submarine sailed for Hawaii on 22 May and reached Pearl Harbor the following week. She sortied for Midway with Task Group 7.2 on the 29th in anticipation of a Japanese attack on that island. Her station was northeast of Midway, and she remained there without contacting any enemy shipping until she was ordered back to Pearl Harbor on 9 June,

On 26 June, Trigger got underway for the Aleutians to patrol an area west of Cape Wrangell, Attu Island. She encountered no enemy shipping before calling at Dutch Harbor on 8 August en route back to Hawaii.

Trigger's second war patrol, conducted from 23 September to 8 November, took her to Japanese home waters. In the early morning hours of 5 October, the submarine sighted smoke on the horizon and headed for it. A vessel soon appeared, coming toward the submarine. As the target approached, the submarine identified it as a small ship. Trigger then surfaced and manned her machine guns. However, when the submarine neared the target, she learned that the Japanese ship was larger than she had at first appeared to be. Enemy shells soon began exploding close to Trigger, and the 4,000-ton ship turned and came on fast in an attempt to ram. The submarine barely avoided a collision as she submerged for an attack. Trigger fired two torpedoes and heard one hit. She then surfaced and gave chase, only to have the target again open fire. The submarine missed with three more torpedoes and then discontinued the pursuit.

Before dawn on the morning of 17 October, Trigger made a surface attack on a freighter off the Bungo Strait. She fired two spreads of torpedoes which sank Holland Maru with her guns still firing. That night, a destroyer came out of Bungo Strait and dropped a string of depth charges near the submarine. Trigger fired three torpedoes "down the throat" at the onrushing Japanese destroyer and, one minute later, observed an explosion so powerful that it threw enough flame and water into the air to obscure the target. When the air cleared, the enemy ship was still intact, suggesting that Trigger's first torpedo may have exploded prematurely, detonating the next two by its turbulence. The submarine fired one more torpedo as the enemy disappeared, but failed to score a hit.

Near midnight of the 20th, Trigger fired a spread of four torpedoes from a range of 900 yards in a surface attack upon a 10,000-ton tanker. Two torpedoes hit the enemy ship as it turned in an attempt to ram. The submarine went to 100 feet to evade a Japanese counterattack and heard a heavy explosion as either gasoline, magazines, or the boilers blew up. She then came up to periscope level but found nothing in sight. Four days later, Trigger attacked a large enemy tanker, riding high in the water. A spread of three torpedoes produced three observed hits, one near the target's stern. The screws of the enemy ship stopped, and she began emitting heavy white smoke aft. But she soon got underway again. Trigger fired her last torpedo at the ship as it was moving off and missed. That night, she surfaced and began her homeward voyage.

From 3 December 1942 to 22 January 1943, the submarine conducted a combined minelaying and offensive patrol in waters surrounding the Japanese home islands. On 20 December, she began planting a minefield off Inubo Saki, Honshu. Trigger planted the northern half of the field and was working on the southern part when a cargo ship passed her, heading into the newly-laid mines. Five minutes later, a violent explosion rocked the freighter which sank as an escort circled her. The submarine later heard another explosion from the direction of the minefield and, when she surfaced the next day, found the field was covered by smoke.

On 22 December, Trigger sighted a ship approaching from Uraga and made a surface attack. A spread of three torpedoes produced one hit forward of the bridge, and the target started to settle by the bow. The submarine fired one more torpedo into the ship and, when last seen, Teifuku Maru was awash forward with her screws nearly out of the water. On 31 December 1942, she attacked a cargo ship loaded with planes. Trigger fired three torpedoes from 700 yards and watched two hit. The target began to list to starboard and was down by the bow. Sound reported a heavy secondary explosion. The submarine came up to periscope level and saw the freighter with her stern high out of the water and a destroyer approaching. She went deep and when she next came up for a look, there was nothing to be seen.

On 10 January 1943, a Japanese destroyer approached Trigger, and the submarine fired three torpedoes from 1,500 yards. One hit under the well deck and folded the destroyer's forecastle up at a 45-degree angle; and another hit the target's stern. Soon Okikaze sank on an even keel.

Trigger stood out of Midway on 13 February to patrol off the Palaus. Two weeks later, she fired four torpedoes at a freighter, but the target managed to steer between them. Heavy air cover prevented a second attack. On 4 March, the submarine attacked a freighter in a rain squall, but all three of her torpedoes missed. On the 15th, Trigger sighted a convoy steaming in two columns. There were two freighters in the right hand column and three in the left with an escort on the outboard bow of each. She worked her way between the two columns and fired three torpedoes at each of the leading ships. She hit the lead freighter in the left hand column twice but missed her target on the right because it unexpectedly changed course. Trigger than fired three more torpedoes at the right lead ship at a range of 700 yards and observed two hits before the escorts forced her to go deep. When she surfaced again, there was nothing to be seen. Trigger was later officially credited with having sunk Momoha Maru, a 3,103-ton cargo ship.

That night, the submarine fired six torpedoes at a ship that was being towed by a smaller freighter. Five of the torpedoes missed, and the sixth made a circular run and passed over the submarine's engine room. A shaken crew broke off the attack.

On 20 March, the submarine fired three torpedoes at the lead ship in a convoy of four cargomen. One hit caused the target to list 10 degrees to port and stop, but it soon got underway and rejoined the convoy. Trigger terminated the patrol at the Submarine Base, Pearl Harbor, on 6 April.

Between 30 April and 22 June, the submarine made a patrol which returned her to Japanese home waters. On 28 May, Trigger contacted two freighters off Iro Saki and launched three torpedoes at the larger. One hit its target aft. When last seen, the ship was down by the stern. The next day, the submarine fired a spread of three torpedoes at a small cargo ship. Two missed and the third exploded prematurely. She then launched a fourth which apparently hit but failed to explode. On 1 June, the submarine was searching for Japanese shipping off Sagami Nada when she sighted two columns of smoke. She closed the range toward a firing position, made out two cargo ships, and fired a spread of three torpedoes at each target. Hit in her stern, the lead ship, Noborikawa Maru, sank immediately. The second ship saw the torpedo wakes, turned, and passed between them. Trigger then fired a torpedo at the oncoming ship; but, if the torpedo reached the target, it failed to explode. On the 10th, Trigger sighted an aircraft carrier protected by, two destroyers. She closed and sent six torpedoes streaking toward the Japanese flattop. The submarine heard four hits before she went deep to avoid the escorts which kept her down for several hours. The damaged carrier Hiyo limped into Tokyo Bay and was out of action for almost a year. The next day, the submarine began her return voyage to Pearl Harbor.

On 1 September, after a yard overhaul, Trigger was ready to begin her sixth war patrol. It took her intothe East China Sea, off the China coast, north of Formosa. On the 17th, she made two hits on a Japanese freighter, one aft and one on the bow, but both torpedoes proved to be duds. The next day, she again contacted the same ship and fired four torpedoes at her. One struck Yowa Maru, and the 6,435-ton cargo ship slid beneath the waves.

The 21st of September was Trigger's best day. She was patrolling some 30 miles north of the Hoka Sho light when she sighted a convoy of three tankers and three freighters protected by Japanese planes. The submarine attacked the tankers first, firing three torpedoes at the leader and three at the second. One hit aft was seen on the lead tanker, and flames shot over 500 feet into the air. Her crew, dressed in whites, could be seen running forward to escape the fire. One torpedo hit the second tanker amidships, and it broke in half beneath the stack and sank immediately. Trigger turned and fired three stern tubes at the third tanker. This target swung toward the submarine, and all three torpedoes missed. Trigger then fired another torpedo which hit the ship's starboard side. When the submarine went deep her commanding officer slipped and fell into the periscope well as the quartermaster was lowering it. He supported himself on his elbows, and the quartermaster heard his shouts in time to prevent a serious accident. Sonar reported two more explosions before the submarine came up to periscope depth to resume the attack. Trigger fired two bow torpedoes at the third freighter in the column and scored two hits on the target which went down by the bow. The submarine then made two more attacks on the freighter, but all of her torpedoes either missed or were duds. During the three and one-half hours of action, Trigger sank two tankers, Shiriya and Shoyo Maru, and a freighter, Argun Maru, for a total of 20,660 tons of enemy shipping. The submarine returned to Midway on 30 September to be refitted and rearmed.

The East China and Yellow Seas were Trigger's objective for her seventh patrol. She stood out of Midway on 22 October and proceeded to her patrol area. At 2200 hours on 1 November, she sighted a convoy that was steaming in two columns. When a ship in the nearer column overlapped one in the more distant group, she fired a spread of three torpedoes at them. One torpedo struck the nearer freighter in her bow and one hit the farther ship amidships. The submarine saw the nearer ship go down by the bow, before she herself was forced to go deep where she was severely depth-charged by two escorts. In the early morning of the 2d, Trigger fired three torpedoes at a freighter and scored one hit. At 0050 hours, she attacked the ship again with a spread of another three. Two of them hit forward, and Yawata Maru went down, bow first, in a vertical plunge. Two hours and 25 minutes later, Trigger fired three torpedoes at a 7,148-ton transport. All torpedoes hit the ship, and Delagoa Maru disintegrated. On 5 November, the submarine attacked a convoy of three cargo ships protected by one destroyer and two planes. Trigger fired three bow tubes at the second ship in the convoy and one bow tube at the third before she went deep to avoid the escort which dropped 20 depth charges. Thinking she was clear, the submarine came to periscope depth and was greeted by five near bomb misses.

On 13 November, Trigger made a submerged approach on a convoy of nine merchantmen and four escorts. After the Japanese ships zigged, the submarine found herself between two columns of ships. But her bow tubes were empty! She attacked the last and biggest ship, believed to be a transport, from a range of 800 yards with a spread of four torpedoes. The target, which carried a large deck cargo, took one hit aft and one under her stack. The submarine went deep, received a short depth charge attack, and came up to periscope depth to learn that her target had gone down. On the 21st, Trigger sighted a cargoman and closed the range to 2,000 yards before firing four torpedoes. Two hits started the victim down by the bow as the submarine's crew took turns at the periscope to watch Eizan Maru sink. More than a fortnight later, the submarine arrived at Pearl Harbor on 8 December 1943. Trigger stood out to sea on New Year's Day 1944 to begin her eighth war patrol, this time in the Truk-Guam shipping lanes. On 27 January, she sighted the conning tower of an .RO-class submarine dead ahead. Trigger set up to fire a bow shot from a range of 800 yards. She came to periscope depth and saw that the Japanese submarine, then less than 100 yards away, was preparing to attack. Trigger went to 150 feet, expecting a torpedo at any minute, but sound heard no torpedo screws. She came up to periscope depth and saw the Japanese periscope so she decided to make an end around. When Trigger returned to periscope depth, the enemy had disappeared.

Four days later, she contacted a convoy of three ships accompanied by two Fit&M/ci-class destroyers. The submarine scored two hits on the coastal minelayer Nasami which disappeared in a cloud of smoke and debris. The nearer destroyer began closing the range, and Trigger missed it with four aft tubes. She caught up with the convoy again and fired five torpedoes at the last ship. Two hits produced flames that reached mast head height and several secondary explosions that marked the end of the 11,933-ton converted submarine tender Yasukuni Maru, Over three weeks later, the submarine terminated the patrol when she arrived at Pearl Harbor on 23 February.

On 23 March, Trigger headed for the Palaus on her ninth war patrol. In the early morning of 8 April, she contacted a convoy of approximately 20 large ships with an estimated 25 escorts and closed to attack. When she raised her periscope, she saw a destroyer 150 feet away firing at the scope and attempting to ram. The submarine loosed four torpedoes at the convoy and went deep as several more escorts joined the attack. On her way down, she heard four explosions. Trigger ran at 300 feet or more for 17 hours as six escorts dogged her trail and rained down numerous depth charges. Six exploded extremely close. When the submarine surfaced, her forward torpedo room was flooded to her deck plates; the hull air induction and most compartments were in about the same condition. The bow planes, trim pump, sound gear, and both radars were all dead. Her radio antenna was grounded, and the submarine could not transmit. The crew spent the next four days making repairs "by use of spares, baling wire, and considerable ingenuity."

Trigger met Tang (SS-306) on the 14th and exchanged information by line gun. The next day, Trigger's executive officer went on board Tang by a rubber boat, to borrow an air compressor part and to make plans for a coordinated search and attack. On the 18th, Tang's executive officer delivered spare parts for the air compressor to Trigger, and she continued on patrol.

Shortly before midnight on the 26th, the submarine contacted a convoy of six ships off the eastern Palaus. She fired six torpedoes, from 2,400 yards, at four ships that were closely bunched and overlapping. Four hits were seen and heard from a big explosion on each ship. Suddenly, a terrific explosion blew up one of the closer ships. One of the more distant ships stood straight up on her bow and then sank immediately. At six minutes after midnight, Trigger fired three torpedoes at a group of ships and heard one timed explosion. At 0157, she fired four torpedoes at a damaged cargo ship and two at an escort. The cargo ship received two more hits. Five minutes later, the submarine fired three stern tubes at a group of three escorts, and the middle one disappeared in a cloud of smoke. During the attack, Trigger sank the 11,739-ton passenger-cargo ship Miike Maru and heavily damaged the destroyer escort Kasado, the 9,467-ton cargo ship Hawaii Maru, and the 8,811-ton cargo ship Asosan Maru. Trigger returned to Pearl Harbor on 20 May and, four days later, headed for the United States for a major overhaul. She arrived at San Francisco on 31 May and, after overhaul, returned to Hawaii on 11 September.

On 24 September, Trigger got underway to take station off the east coast of Formosa and perform life guard patrol for bomber strikes due on 12 October. The morning of the strikes, she rescued a pilot from Bunker Hill (CV-17) whose burning plane had crash-landed nearby. On the 19th, as the invasion of the Philippines was about to begin, she contacted a convoy of two Atago-class cruisers, one jVotori-class, two other light cruisers, and several destroyers with air cover. Trigger had no chance to fire but reported the contact. On 30 October, she fired four torpedoes at a tanker but missed. She then fired another four from her stern tubes and heard one hit the target before running up the periscope to watch the other three blow off part of the stern, but the ship did not sink. Trigger went deep as 78 depth charges were rained down on her within the next hour but caused no damaged. The damaged 10,021-ton tanker Takane Maru was later sunk by Salmon (SS-182) and Sterlet (SS-392). The next morning, Trigger received word from Salmon that she had been heavily damaged by depth charges and was unable to submerge. Trigger rendezvoused with Salmon that night and was joined by Silversides (SS-236) and Sterlet to escort the damaged submarine to Saipan. They were provided with air cover from the Marianas and arrived at Tanapag Harbor on 3 November. A week later, Trigger departed with six other submarines but was ordered to discontinue her patrol on the 17th and returned to Guam.

On 28 December 1944, Trigger headed for the Bungo Strait-Kii Strait area to begin her llth war patrol. At 2105 on 3 January 1945, she sighted a light; and radar made a doubtful contact. Thirty minutes later, a torpedo passed by her starboard side. She reversed course and cleared the area but returned two days later. That day, she sighted a periscope at 2,000 yards; and, realizing that instead of hunting, she was being hunted, she slipped away.

On the 29th, she made radar contact from 23,000 yards on a large convoy with six escorts and well-covered by aircraft. As she closed, the moon came out bright and clear. An enemy bomber turned and started in as radar picked up another plane coming in astern at 5,000 yards. The submarine went deep, and the convoy slowly pulled away. The next day, the ship was ordered to terminate her patrol, and she returned to Guam on 3 February.

Trigger stood out to sea on 11 March to begin her 12th war patrol and headed for the Nansei Shoto area. On the 18th, she attacked a convoy west of the islands, sinking the cargo ship Tsukushi Maru No. 3 and damaging another. The attack was reported on the 20th, and the submarine was subsequently ordered to radio as many movements of the convoy as possible to help find a safe passage through a known mined area of the East China Sea. On the 24th, Trigger was ordered to begin patrolling west of the islands the next day, outside the 100 fathom curve, and to steer clear of restricted areas. On the 26th, she was ordered to join a wolf pack called "Earl's Eliminators" and to acknowledge receipt of the message. A weather report came from the submarine that day but no confirmation of her having received the message. The weather report was Trigger's last transmission. On 4 April, she was ordered to proceed to Midway, but she had not arrived by 1 May and was reported as presumed lost.

Post-war records indicate that she torpedoed and sank the repair ship Odate on 27 March. The next day, Japanese planes and ships joined in a two-hour attack on a submarine at a position 32°16' N. and 132°OB' E. The attack was heard by Silversides (SS-236), Seadog (SS-401), Hackleback (SS-295), and Threadfin (SS-410) in adjacent areas. Threadfin was the only one of these submarines that had been attacked that day, and she reported that she heard many depth charges and several heavy explosions east of her position after the attack on her ceased. Trigger was struck from the Navy list on 11 July 1945.

Trigger received 11 battle stars for World War II service and the Presidential Unit Citation for her fifth, sixth, and seventh war patrols.

Published: Wed Sep 30 19:00:34 EDT 2015