< Wahoo SS-238

Wahoo SS-238

 

Wahoo
(SS-238: dp. 1,525 (surf.), 2,424 (subm.), 1. 311'10"; b. 27'4"; dr. 15'2" (mean) ; s. 20.25 k. (surf.), 8.75k. (subm.); cpl. 60; a. 10 21" tt., 1 3", 2 .30-car. mg., 2.50-cal. mg.; cl. Gato)

The first Wahoo (SS-238) was laid down on 28 June 1941 by the Mare Island Navy Yard, Vallejo, Calif launched on 14 February 1942; sponsored by Mrs William C. Barker, Jr.; and commissioned on 15 May 1942, Lt. Comdr. Marvin Granville Kennedy in command.

Following fitting out and initial training along the California coast which took the submarine as far south as San Diego, Wahoo departed San Francisco on 12 August, bound for Hawaii. She arrived at Pearl Harbor on 18 August and underwent exercise training until the 21st.

Two days later, the ship got underway for her first war patrol and stalked enemy shipping in waters near Truk, particularly in the area between the Hall Islands and the Namonuito Atoll. On 6 September, Wahoo fired three torpedoes at her first target, a lone freighter, but all probably missed, because the ship turned and headed for Wahoo. Wahoo "kept going," fearful of counterattack from the air. This retreat was a damaging blow for the crew. As one crew member put it, "After the exhausting months of drills, it was demoralizing to creep away submerged from that first target."

The submarine continued to patrol the Truk area until 20 September when she decided to leave the southwest part of the patrol area and explore south of the Namonuito Atoll. Under a bright moon and clear sky, the submarine sighted a freighter and her escort. Wahoo fired three torpedoes, all three missed. A fourth torpedo hit the target, which took a port list and settled bodily and by the stern. Four minutes later, a series of three underwater explosions racked the freighter. Wahoo was chased by the escort but escaped by radically changing course in a rain squall. Kennedy claimed a freighter of 6,400 tons, but postwar analysis of Japanese shipping records showed no sinking at this time or place.

Wahoo continued her patrol and sighted several airplanes, a patrol boat, and a tender but was unable to to close on any possible targets. On 1 October 1942, the submarine extended her patrol to Ulul Island where she sighted several fishing boats. Within the next few days, Kennedy would miss two of the best targets of the war. The first was aircraft tender Chiyoda, which came along without an escort. Kennedy did not have time to get into position to shoot. On 5 October, Wahoo sighted an aircraft carrier which Kennedy believed to be Ryujo, sunk six weeks earlier in the Solomons. Whatever it was, it came into sight escorted by two destroyers. Due to an approach, which Kennedy later admitted lacked aggressiveness and skill, the target sailed away untouched. Two days later, Wahoo departed the patrol area. On 16 October, she made rendezvous with her escort and proceeded to Pearl Harbor.

Wahoo arrived at Hawaii on 17 October 1942 from her first war patrol and commenced refit the following day alongside Sperry (AS-12). She then shifted to the Submarine Base, Pearl Harbor, for overhaul. There a 4-inch gun and two 20-millimeter guns were installed. Overhaul was completed on 2 November; and, after a three-day training period, Wahoo was ready for sea.

On 8 November 1942, Wahoo got underway for her second war patrol in company with the small escort vessel PC-23. She arrived at her assigned area in the Solomon Islands and continued her patrol, keeping in sight of Bougainville and Buka Islands. On 30 November, the submarine spotted smoke at a distance of 8,000 yards. Wahoo sighted a lightly burdened freighter or transport with a destroyer escort on station on the port bow of the target. The submarine's approach was unsuccessful, and she proceeded east of Cape Hanpan.

Having patrolled the Buka-Kilinailau Channel for 17 days, on 7 December, the submarine decided to patrol the direct route between Truk and the Shortlands for a few days. This proved fruitless, and Wahoo returned to her former hunting grounds the Buka-Kilinailau Channel. On 10 December, while making her return trip, Wahoo ran across a convoy of three heavily loaded cargo ships escorted by a destroyer. She chose the largest tanker as the first target and fired a spread of four torpedoes at a range of 700 yards. Although three torpedoes hit, it took two hours for the Kamoi Maru to sink. The destroyer got too close and Wahoo started down before another attack could be launched. The destroyer dropped approximately 40 depth charges which were fairly close aboard, causing minor damage. Kennedy was urged to mount a second attack. Using the new SJ radar, executive officer Mush Morton and Lt. Dick O'Kane argued, it would be easy to knock off the freighter and possibly the destroyer. However Kennedy had had enough. Wahoo moved into a new area, and the convoy continued on to the northeast.

Four days later, a hospital ship was sighted headed for the Shortlands. Wahoo then sighted a submarine proceeding singly on the surface with the designation I-2 painted on the side of the conning tower. Wahoo fired a divergent spread of three torpedoes at a range of 800 yards. The first torpedo hit 20 feet forward of the conning tower. The boat went down with personnel still on the bridge. In postwar records, however, Wahoo was not credited with this sinking. On 15 December, she left the area and looked into Kieta Harbor, Buka Island, and passed Moreton Light on the 26th for entrance into Brisbane, Australia, where she commenced refit the following day. On 31 December, Lt. Comdr. Marvin Granville Kennedy was relieved as commanding officer by Lt. Comdr. D. W. Morton.

Morton had served as executive officer of Wahoo during her first two patrols under Kennedy. Morton, endeared to his Annapolis classmates as "Mushmouth" (abbreviated "Mush") because of a knack for yarnspinning, was an uncommonly talented submarine officer. Before Wahoo left Brisbane on her third war patrol, her first under "Mush" Morton, the skipper gave the crew a flaming pep talk. Morton said, "Wahoo is expendable. We will take every reasonable precaution, but our mission is to sink enemy shipping.... Now, if anyone doesn't want to go along under these conditions, just see the yeoman. I am giving him verbal authority now to transfer anyone who is not a volunteer.... Nothing will ever be said about your remaining in Brisbane." No one asked for a transfer, and this speech inspired a new spirit amongst the crew, a feeling of "confidence in the capabilities and luck" of Wahoo and the thought that she was "capable of performing miracles."

Of the many innovations Morton had put into effect on Wahoo, the most extraordinary was having the executive officer, Dick O'Kane, not the captain, man the periscope. George Grider, a junior officer, commented: "This," he explained, "left the skipper in a better position to interpret all factors involved, do a better conning job, and make decisions more dispassionately. There is no doubt it is an excellent theory, and it worked beautifully for him, but few captains other than "Mush" ever had such serene faith in a subordinate that they could resist grabbing the scope in moments of crisis." Thus evolved the successful and renowned duo of Morton and O'Kane.

Wahoo was ready for sea on January 1943. She commenced sound listening test. in Moreton Bay, then fell in with her escort, Patterson (DD-392), to begin her third war patrol. Three days later, the submarine passed into Vitiaz Strait en route to her patrol area. Wahoo's orders were to reconnoiter Wewak, a Japanese supply base on the north coast of New Guinea. There was one large problem about reconnoitering Wewak: Wahoo had no charts of the harbor. However, it turned out that one of the motor machinists had bought a
cheap school atlas while in Australia. It had a map of New Guinea with a small indentation labeled "Wewak." With that as a reference, Morton located the unmarked area on a large Navy chart and had a blowup made of the Navy chart with an ingenious device composed of a camera and signal lights. Then, to the crew's amazement, they learned that Morton's definition of "reconnoiter" meant to penetrate the harbor and-sink whatever ships could be found.

On 24 January 1943, Wahoo dove two miles north of Kairiru Island and proceeded around the western end to investigate Victoria Bay. She sighted a destroyer with RO-class submarines nested around it. The destroyer was getting underway, so Morton fired a spread of three torpedoes at the moving target. They missed and were observed going aft. Another fish was fired which the destroyer avoided by turning away, then he circled right and headed for Wahoo. The submarine watched the ship come, and she kept her bow pointed at it. Morton delayed firing the fifth and last torpedo in the forward tubes until the destroyer had closed to a frightening distance of 800 yards. This torpedo clipped him amidships "and broke his back. The explosion was terrific." The topside was covered with Japanese on turret tops and in the rigging. Over 100 members of the crew must have been acting as lookouts. The target's bow was settling fast, and her boilers were heard to explode. Wahoo had no difficulty escaping the area. Morton was certain that the destroyer sank. However, he was not credited with a kill.

The next day, Wahoo changed base course for Palau. On 26 January, the submarine sighted the smoke of two freighters, obtained a position, and fired two torpedoes at the leading ship and, 17 seconds later, two at the second freighter. The first two torpedoes hit their points of aim in bow and stern. The third torpedo passed ahead of the second freighter, but the fourth torpedo was a hit. Upon observation of the damage, Wahoo discovered that there were two freighters, a huge transport, and a tanker. The leading freight was listing badly to starboard and sinking by the stern; the second ship was headed directly for Wahoo, but at a slow speed. Wahoo fired a three-torpedo spread at the transport; the second and third torpedoes hit and stopped him.

Turning her attention to the second target, Fukuei Maru No. 2, which was still headed for her, Wahoo fired two bow torpedoes "down the throat" to stop him. The second torpedo hit, but he kept coming and forced the submarine to turn hard left at full speed to avoid being rammed. There followed so many explosions that it was hard to tell what was happening. Coming to periscope depth, Wahoo observed that the first target had sunk the second target was still moving, evidently with steering trouble; and the transport, Buyo Maru, was stopped but still afloat. Wahoo headed for the transport and fired a bow torpedo which passed directly under the middle of the ship but failed to explode. She then fired another torpedo which headed right for the stack and blew her midships section "higher than a kite." Troops jumped over her sides "like ants off a hot plate." Her stern went up, and Buyo Maru headed for the bottom. The submarine then headed for the crippled second target which had joined with a tanker. Wahoo decided to let these two ships get over the horizon, while she surfaced to recharge her batteries and to destroy the estimated 20 troop boats now in the water. The water was so thick with enemy soldiers that it was literally impossible 'to cruise through them without pushing them aside like driftwood.

Wahoo changed course to intercept the two fleeing ships. She decided to attack the tanker first since she was as yet undamaged. With only four torpedoes left the submarine fired two at the tanker, the second hitting him just abaft of his midships, breaking his back. He went down almost instantly. Wahoo then turned her attention to the freighter and fired her last two torpedoes without a spread. They both hit; and 15 minutes later, the freighter sank. It had required four hits from three separate attacks to sink this ship. Wahoo then set a course for Fais Island. That night, Morton drafted a triumphant report for Pearl Harbor "In ten hour running gun and torpedo battle destroyed entire convoy of two freighters one transport one tanker . . . all torpedoes expended." However, postwar Japanese shipping records only credited Wahoo with three sinkings for this date: the transport, Bugo Maru, 5,300 tons, Fukuei Maru, 2,000 tons; and an unknown maw, 4,000 tons.

On 27 January 1943, Wahoo made contact with a convoy of eight ships, including two freighters and a tanker. However, efforts to gain a position were foiled by a persistent destroyer escort who dropped six depth charges. The submarine had no option but to retreat since she had previously expended all torpedoes. The next day, Wahoo sighted Fais Island, and her plan to shell a phosphorite refinery was scrapped due to the untimely appearance of an inter-island steamer.

The submarine departed for Hawaii and arrived there on 7 February, 23 days after leaving Brisbane. For her entrance into Pearl Harbor, Wahoo had donned topside embellishments to celebrate her victory. There was a straw broom lashed to her periscope shears to indicate a clean sweep. From the signal halyard fluttered eight tiny Japanese flags, one for each Japanese ship believed to have been sunk in all three of Wahoo's patrols. Morton was nicknamed "The One-Boat Wolf Pack" and awarded a Navy Cross. From Port Moresby, General MacArthur awarded Morton an Army Distinguished Service Cross.

Wahoo commenced refit by a tender relief crew and the ship's force. On 15 February, refit was completed, and the submarine was declared ready for sea on 17 February. She then conducted two days of training and was drydrocked at the Submarine Base, Pearl Harbor, on 21 February.

On 23 February 1943, Wahoo got underway for Midway, where she arrived four days later, topped off, and headed for her patrol area. For Wahoo's fourth patrol, Morton was assigned an area never before patrolled by United States submarines: the extreme northern reaches of the Yellow Sea, in the vicinity of the Yalu River and Dairen. One reason for this was that the water was extremely shallow, averaging 120 feet. But the "wading pond" barely fazed Morton, he welcomed virgin territory. From 27 February to 11 March, the submarine was en route to her patrol area, conducting training dives, fire control drills, and battle surface drills. She had the unique experience of making the entire passage to the China Sea without sighting a single aircraft; thus making the entire trip on the surface. On 11 March, Wahoo commenced a submerged patrol in her assigned area and along the Nagasaki-Formosa and Shimonoseki-Formosa shipping routes.

On 19 March 1943, the shooting began with a freighter identified as Zogen Maru. A single torpedo was fired, and it hit the after part of the ship, causing it to disintegrate upon impact. The forward part of the freighter sank two minutes later. There were no survivors Four hours later, Wahoo sighted a new freighter, Kowa Maru, and fired two torpedoes. The first torpedo hit under the target's foremast with a terrific blast, but his bow remained intact. However, a tremendous hole up his side was visible. The second torpedo hit amidships, but it was a dud. Two more torpedoes were fired, but the freighter maneuvered and avoided them. That defective torpedo cost Wahoo a victim, plus the opportunity to shoot more targets at this location.

Wahoo then patrolled off the Korean coast, just south of Chinnampo. On 21 March, she sighted a large freighter identified as Hozen Maw. She fired three torpedoes, and the third torpedo hit the target amidships. The Japanese freighter was literally disemboweled. He went down by the bow, attaining a near vertical angle and was out of sight in four minutes, leaving approximately 33 survivors clinging to the debris.

Four hours later, Wahoo sighted the freighter Nittsu Maru. The submarine fired a spread of three torpedoes; two torpedoes hit the target, one under his bridge and the other under his mainmast. The ship went down vertically by the bow and was out of sight in three minutes. Four survivors remained who ignored all efforts to rescue them. After collecting a few souvenirs from the scattered wreckage, Wahoo commenced a surface patrol, heading for Shantung Promontory. On 22 March, the submarine headed for Laotiehshan Promontory, just around the corner from Port Arthur.

The following day, Wahoo patrolled Laotiehshan Channel, also known as "Sampan Alley;" the submarine was literally surrounded by them. Wahoo sighted a medium-size freighter and fired one torpedo. This hit collier Katyosan Maru just under the bridge immediately enveloping her in a screen of coal dust. She settled fast and slowed down; 13 minutes later, nothing was seen of her.

Morton set a course for a point to the northeast of Round Island, off Dairen. In the vicinity of the port's approaches, the deepest water is about 50 fathoms, with an average depth of around 20 fathoms. The Yellow Sea was no place for a submarine to be caught unawares. In water that shallow, depth charges would go off "like firecrackers in a birdbath."

On 24 March, at 1247, Wahoo sighted smoke and began to make her approach. At 1949, she fired a spread of three torpedoes at a large tanker which was fully loaded with fuel oil. The first two torpedoes exploded prematurely, and the third missed. Wahoo fired a fourth shot, and it, too, missed. The target commenced shooting at Wahoo. The submarine surfaced after 14 minutes of ducking shots, gained position ahead, and dove. She fired another three torpedo spread. The torpedo hit the engine room and sank the ship in four minutes. The tanker was identified as Takaosan Maru.

The next day, Wahoo sighted freighter Satsuki Maru. She fired a spread of two torpedoes; but, when each exploded prematurely, Morton ordered a battle-surface. The submarine closed in on the target and raked him with 20-millimeter shells and holed him with almost 90 rounds of 4-inch. The target caught fire in several places and sank in about one hour

Wahoo left on the following morning to investigate a ship on the horizon, which proved to be a small dieseldriven freighter. The submarine commenced firing with her 20-millimeter and 4-inch guns. The freighter tried to ram the submarine, but Wahoo had no trouble in keeping clear. She continued her gunfire and had the freighter blazing from stem to stern and dead in the water. The crew alternated looks through the periscope as the freighter sank.

Later that day, Wahoo sighted a 100-ton trawler and opened up with her 4-inch and 20 millimeter guns When all three 20-millimeter guns jammed, Morton brought the submarine alongside the riddled trawler and the Wahoo men hurled on board some homemade Molotov cocktails, gifts from the marines at Midway. Wahoo departed, leaving the ship in a wrecked condition, spouting flame and smoke. On 28 March, while conducting a surface patrol on the Shimonoseki-Formosa shipping routs, Wahoo opened fire on two lighted motor sampans with two 20-millimeter guns. They did not sink but were also left in a wrecked condition.

The following day, the submarine sighted the freighter Yamabato Maru and fired two stern shots. The first torpedo hit at the point of aim under the mainmast and completely disintegrated everything abaft of the stack. The forward section sank in two minutes. The second torpedo was aimed at the foremast; it missed because the first torpedo stopped the freighter in its tracks.

Wahoo surfaced, transited Collnett Strait, and headed for her base, thus concluding a war patrol which topped the record to that date in number of ships sunk. When Morton reported his results to Pearl Harbor, the reply was: "Congratulations on a job well done . . . Japanese think a submarine wolf pack operating in Yellow Sea. All shipping tied up."

Meanwhile, the United States mounted its offensive against Attu, and Admiral Koga returned his major units from Truk to Tokyo Bay for the sortie to Alaska. Forewarned by codebreakers that the Japanese intended to counter the Attu invasion by a major sortie of the fleet, Lockwood sent his top skipper to the Kurils to intercept it, "Mush" Morton in Wahoo

On 6 April 1943, Wahoo arrived at the Submarine Base, Midway Island, and commenced refit the following day. On the 21st and 22d of April, the submarine conducted training exercises underway and was declared ready for sea on 25 April.

Wahoo began her fifth war patrol on 25 April, departing Midway under air escort for patrol areas via the Kuril Islands. The following day, she commenced a surface patrol along the Kuril Islands and reconnoitered Matsuwa, taking photographs of the enemy installations there. The submarine explored the islands of the Kuril chain to the southwest and found them to be barren and completely covered with snow and ice.

On 4 May, Wahoo proceeded to reconnoiter the northeast tip of Etorofu Island, she found nothing and changed course to the southeast. Morton was positioned to intercept a seaplane tender, Kamikawa Maru. The submarine sighted the target and fired a divergent spread of three torpedoes. The first torpedo hit between the stack and bridge, the other two shots missed. Kamikawa Maru turned away and was making 11 knots, with a slight list. Wahoo continued on an easterly course, surfaced and continued her patrol of the Kuril chain southward.

Three days later, Wahoo submerged 12 miles off the Benten Saki coast and sighted two ships hugging the shoreline on a northerly course. She fired a spread of two torpedoes at the leading ship, followed immediately by a spread of four torpedoes at the escort. The first torpedo hit the leading ship, Tamon Maru No. 5, under the stack and broke her back; the second torpedo missed ahead. The escort successfully avoided all four torpedoes fired at her and escaped. Tamon Maru, 5,260 tons, sank, and Wahoo proceeded down the coast.

The submarine submerged one mile off Kobe Zaki and sighted a three-ship convoy consisting of two escort vessels and a large naval auxiliary. Wahoo fired a spread of three torpedoes; two exploded prematurely, and the third hit but failed to explode. This ship got away, and Morton was forced down by the escorts.

On 9 May 1943, Wahoo proceeded up the coast with the intention of closing Kone Saki. The radar operator picked up two targets, soon identified as a large tanker and a freighter in column. They were evidently making the night run between ports without an escort. The submarine fired a spread of three torpedoes at the tanker and immediately thereafter a three torpedo spread at the freighter. Wahoo had two successful hits, and both ships went down, Takao Maru, 3,200 tons and Jinmu Maru, 1,200 tons.

Morton cleared the area to the northeast to patrol the Tokyo-Paramushiro route. Wahoo continued her patrol; and, on 12 May, she sighted two freighters. The submarine dove to gain position for a "two ship" shot where they would come by in column. She fired four torpedoes from 1 200 yards, only one was a hit. Then Morton fired his last two remaining torpedoes. Nothing was seen of the first torpedo or its wake. The second shot hit under the bridge with a dull thud, much louder than the duds heard only on sound but lacking the "whacking" noise which accompanies a wholehearted explosion. It is considered that this torpedo had a low order detonation. The other freighter opened fire with heavy guns and charged Wahoo. The submarine was helpless to stop the two ships. Morton cleared the area to the east and set a course for Pearl Harbor.

Wahoo's fifth war patrol was again outstanding in aggressiveness and efficiency. In 10 action-packed days Wahoo delivered 10 torpedo attacks on eight different targets. However, faulty torpedo performance cut positive results probably by as much as one-half.

This was "Mush" Morton's third patrol as commanding officer of Wahoo. These three patrols established a record not only in damage inflicted on the enemy for three successive patrols, but also for accomplishing this feat in the shortest time on patrol. Wahoo had sunk a total of 93,281 tons and damaged 30,880 more in only 25 patrol days.

Wahoo arrived at Pearl Harbor on 21 May 1943. The next day, Admiral Chester W. Nimitz, Commander in Chief, U.S. Pacific Fleet, came on board and made presentations of awards. A gold star, in lieu of a second Navy Cross, was presented to Comdr. Dudley W. Morton. On 23 May, the submarine departed for the Navy Yard, Mare Island, Calif., and she arrived six days later to commence overhaul. From 11 to 20 July the submarine underwent intensive post-repair trials and training. On 20 July, Capt. John B. Griggs, Jr., came on board and made presentations of awards. The following day, Wahoo departed for Pearl Harbor, furnishing services for surface and air forces while en route. She arrived at Hawaii on 27 July 1943 and departed on 2 August for her patrol area. Four days later, Wahoo arrived at Midway but left the same day.

On 13 August, Wahoo entered the Sea of Okhotsk having completed passage through the Etorofu Strait. She arrived in the Sea of Japan the following day and sighted three medium freighters headed south. The submarine fired one torpedo at the trailing ship, but it missed. On 15 August, Wahoo sighted a large freighter on a northerly course and broke off the chase on the three freighters. She commenced a surface tracking of the new target and dove for a submerged approach. Morton fired one torpedo which hit at the point of aim but was a dud and failed to explode. She fired two more torpedoes, and both missed. Wahoo then swung and headed directly for the target, which presented a good up-the-stern shot. The submarine fired another torpedo which missed and must have broached and exploded before the end of the run. Wahoo soon sighted an Otoriclass torpedo boat and commenced evading. She decided to move over on the Hokkaido-Korea shipping route and spend the night and the following day.

On 16 August, Wahoo sighted a freighter headed south but made another contact in a better position for attack. Shifting targets, she fired one torpedo at a medium freighter; however, it missed. The next day the scene was repeated with the same results. Morton decided not to chase this ship north but to wait for a loaded one heading south. However, Wahoo sighted a partially-loaded freighter heading north, and she commenced a submerged approach. Wahoo fired one torpedo which missed. Just as Wahoo fired, a southbound freighter and this target passed each other close aboard; still no hit. She then surfaced and chased the southbound freighter. While pursuing this ship, the submarine sighted another target well ahead and away from the coast, so she shifted targets. While tracking this new target, she passed two small northbound ships —one looked like a tug and the other resembled a tanker. Wahoo made a submerged approach and fired a torpedo at the medium sized freighter. It was a miss. She fired again; still a miss, but this torpedo, probably broaching, exploded. The submarine surfaced and headed further away from the coast.

Wahoo had the worst possible luck with her torpedoes. Within four days, 12 Japanese vessels were sighted; nine were hunted down and attacked to no avail. Ten torpedoes broached, made erratic runs, or thumped against target hulls "like derelict motorboats." Morton wrote in wrath, "Damn the torpedoes!" He reported the poor torpedo performance to ComSubPac and received orders to return to base.

On 19 August, the submarine sighted a ship and commenced tracking. However, she withheld fire when she recognized the flag as Russian. Wahoo then headed for La Perouse Strait. The next day, she sighted a sampan and fired warning shots across the bow. When the sampan failed to stop, the submarine opened up on it with her 20-millimeter and 4-inch guns. The sampan was soon a wreck with no signs of life. However, six Japanese fishermen surrendered and were taken on board as prisoners of war. Eight hours later, Wahoo opened fire on two more sampans enveloping the ships in flames. Members of the crews Jumped overboard but showed no desire to be rescued. Wahoo completed the passage of Etorofu Strait and arrived at Midway on 25 August. She immediately got underway for Pearl Harbor and arrived there on 29 August.

"Mush" Morton, smarting from his last luckless patrol, asked to return to the Sea of Japan, and permission was granted. On 9 September, Wahoo got underway from Pearl Harbor, topped off at Midway on 13 September, and headed for La Perouse Strait. The plan was for Morton to enter the Sea of Japan first, on or about 20 September, with Sawfish (SS-276) following by a few days. At sunset on 21 October, Wahoo was supposed to leave her assigned area, south of the 43d parallel, and head for home. She was instructed to report by radio after she passed through the Kuril chain. Nothing further was ever heard from Morton in Wahoo.

On 5 October, the Japanese news agency, Domei, announced to the world that a steamer was sunk by an American submarine off the west coast of Honshu near Tsushima Strait, with the loss of 544 lives. This was the 8,000-ton Konron Maru. In addition, JANAC showed that Morton sank three other ships for 5,300 tons, making the total for this last patrol four ships amounting to about 13,000 tons. Japanese records also reported that, on 11 October, the date Wahoo was due to exit through La Perouse Strait, an antisubmarine aircraft found a surfaced submarine and attacked dropping three depth charges. Sawfish had been depthcharged by a patrol boat while transiting the strait two days before, and the enemy's antisubmarine forces were obviously on the alert in that area. There could be little doubt that this attack fatally holed Wahoo, and that she sank, taking down "Mush the Magnificent" and all hands. Wahoo was announced overdue on 2 December 1943 and stricken from the Navy list on 6 December 1943.

The loss of Morton and Wahoo caused profound shock in the submarine force. All further forays into the Sea of Japan ceased, and it was not again invaded until June 1945, when special mine detecting equipment was available for submarines. Morton was posthumously awarded a fourth Navy Cross. When he died, his claimed sinkings exceeded those of any other submarine skipper: 17 ships for 100,000 tons. In the postwar accounting, this was readjusted to 19 ships for about 55,000 tons. This left Morton, in terms of individual ships sunk, one of the top three skippers of the war. So ended the career of one of the greatest submarine teams of World War II—Wahoo and "Mush" Morton.

Wahoo earned six battle stars for World War II service.