Gato Class Submarine
1,526 Tons (surfaced)
Wahoo's 3-5 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: a total of 93,281 tons sunk and 30,880 damaged in only 25 patrol days.
First patrol (August - October 1942)
Wahoo continued her patrol and sighted several airplanes, a patrol boat, and a tender but was unable to close. On 1 October 1942, patrolled to Ulul Island where she sighted fishing boats. Next she sited Chiyoda sailing without escort, but was unable to reach a firing position. On 5 October, she sighted an aircraft carrier escorted by two destroyers, but was not able to reach it. Two days later, Wahoo departed the patrol area. On 16 October Wahoo rendezvous with her escort and proceeded to Pearl Harbor, arrving there on 17 October 1942. At refit and overhaul began, including adding a 4" gun and two 20mm guns completed by 2 November and three days training.
Second patrol (December 1942)
On 10 December while returning to Buka-Kilinailau Channel, Wahoo discovered a convoy of three 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 (640 m). Although three hit, it took two hours for Kamoi Maru (5300 tons) to sink. The destroyer got too close and Wahoo started down before another attack could be launched. The destroyer dropped approximately 40 depth charges. Rather than use the new SJ radar to mount a second attack, Wahoo let them go on a northeastrly course. Four days later, a hospital ship was sighted, but not attacked.
On 15 December, Wahoo left the area and for Kieta Harbor, then completed the patrol on 26 December arriving at Brisbane, for refit. On 31 December, Lt. Comdr. Kennedy was relieved as commanding officer for being unproductive. Dudley W. "Mush" Morton, who served as a prospective Commanding Officer during Wahoo's second patrol, replaced him as captain.
Third patrol (January - February 1943)
Off Wewak, Wahoo attacked Harusame off Kairiru Island, in an attack with three torpedos that missed. Another was fired which the destroyer avoided by turning away, then circled and headed for Wahoo. Wahoo waited until the destroyer had closed to 800 yards before firing the fifth and last torpedo in the forward tubes. It struck amidships, damaging it. Wahoo escaped the area dispite enemy searches and attacks, then proceeded towards Palau.
On 26 January, the submarine sighted the smoke of two freighters, and fired two torpedoes at the leading ship and two at the second. The first two torpedoes hit. The third passed ahead of the second freighter, the fourth hit. Upon observing the damage, Wahoo discovered there were two freighters, a huge transport, and a tanker. The leading freighter was listing badly to starboard and sinking by the stern; the second ship was headed directly for Wahoo, at a slow speed. Wahoo fired a three-torpedo spread at the transport; the second and third hit and stopped her.
The second target headed for her was Fukuei Maru #2. Wahoo fired two bow tubes "down the throat". The second torpedo hit, but Fukuei Maru #2 kept coming and forced the submarine forcing it a hard left turn full speed to avoid being rammed. Returning to periscope depth, Wahoo observed 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 tube; the torpedo 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 apart her midships. The submarine then headed for the crippled second target which had joined with a tanker. Wahoo let these two ships escape, while she surfaced to charge her batteries and destroy the estimated twenty lifeboats now in the water.
Wahoo changed course to attack the two fleeing ships, attacking the tanker first. With only four torpedoes left, the submarine fired two at the tanker, the second hitting her just abaft of his midships, breaking her back and causing it to sink almost instantly. Wahoo then fired her last two torpedoes without a spread. They both hit. Fifteen minutes later, the freighter sank. Wahoo then set a course for Fais Island. Postwar records revealed ony three ships were three sunk: Buyo Maru (5300 tons), Fukuei Maru (2000 tons), and an unknown maru (4000 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. Wahoo retreated as she had no torpedoes left. 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.
Wahoo departed for Pearl Harbor on 7 February. When they arrived, Wahoo crew tied a straw broom lashed to her periscope to indicate a clean sweep. The sub was refit until 15 February, training and and was drydrocked.
Fourth Patrol (February - April 1943)
On 19 March 1943, she located freighter 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 freighter Kowa Maru, and fired two torpedoes. The first hit under the target's foremast with a terrific blast, leaving a tremendous hole up her side, but her bow remained intact. The second hit amidships; it was a dud. Two more torpedoes were fired, but the freighter maneuvered to avoid.
Wahoo patrolled off Korea, just south of Chinnampo. On 21 March, she sighted a large freighter identified as Hozen Maru. She fired three torpedoes, and the third hit the Japanese freighter amidships. She went down by the bow, sinking in four minutes.
Four hours later, Wahoo sighted the freighter Nittsu Maru. The submarine fired a spread of three torpedoes; two hit, one under her bridge and the other under her mainmast. The ship went down in three minutes. Four survivors ignored all efforts to rescue them. After collecting a few souvenirs from the scattered wreckage, Wahoo commenced a surfaced patrol, heading for Shantung. On 22 March, the submarine headed for Laotiehshan near Port Arthur.
The following day, as Wahoo patrolled Laotiehshan Channel, also known as "Sampan Alley", she found herself surrounded by targets. Wahoo sighted a medium-size ship, apparently a freighter, and fired one torpedo. This hit Katyosan Maru just under the bridge, immediately enveloping her in a screen of coal dust. She settled fast and slowed down, vanishing in 13 minutes.
Wahoo set a course for a point to the northeast of Round Island, off Dairen. On 24 March, at 12:47, Wahoo sighted smoke and began to make her approach. At 19:49, she fired a spread of three torpedoes at a large tanker which was fully loaded with fuel oil. The first two exploded prematurely, the third missed. Wahoo fired a fourth shot; it also missed. The target commenced firing deck guns at Wahoo. The submarine surfaced after 14 minutes of ducking shots, gained position ahead, and dove. She fired another three torpedo spread. One 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 Wahoo Maru. She fired two torpedoes; when both exploded prematurely, so Wahoo battle surfaced to use her guns. She closed the target, raked her with 20-millimeter shells and holed her with almost 90 rounds of four-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 diesel-driven freighter. The submarine commenced firing with her 20mm and 4" guns. The freighter tried to ram, but Wahoo had no trouble in keeping clear. She continued her gunfire, seting the freighter ablaze from stem to stern and leaving her 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 four-inch and 20mm guns. When all three 20mm guns jammed, Wahoo went alongside the riddled trawler and the Wahoo men hurled on board some homemade Molotov cocktails. Wahoo departed, leaving the ship wrecked, spouting flame and smoke. On 28 March, while conducting a surfaced patrol on the Shimonoseki-Formosa shipping route, Wahoo opened fire on two motor sampans with two 20mm guns. They did not sink but were also left wrecked.
The following day, the submarine sighted the freighter Yamabato Maru and fired two stern tubes. 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 home, concluding a war patrol which topped the record to date in number of ships sunk. Pearl Harbor reported, "Japanese think a submarine wolf pack operating in Yellow Sea. All shipping tied up." On 6 April 1943, Wahoo arrived at Midway for refit and training until the 25th.
Fifth Patrol (April - May 1943)
On 4 May, Wahoo reconnoiter the northeast tip of Etorofu Island; she found nothing and changed course to the southeast. After siting the Kamikawa Maru and fired a divergent spread of three torpedoes. The first hit between the stack and bridge; the other two missed. Kamikawa Maru turned away and was making 11 knots with a slight list. Wahoo continued on an easterly course, surfaced and continued to patrol the Kurils southward.
Three days later, Wahoo sighted two ships hugging the shoreline on a northerly course, 12 miles (22 km) off the Benten Saki coast, and dived. She fired two torpedoes at the leading ship, followed immediately by a spread of four at the escort. The first torpedo hit the leading ship, Tamon Maru #5, under the stack and broke her back; the second missed ahead. The escort successfully avoided all four torpedoes fired at her and escaped. Tamon Maru (5260 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, the third failed to explode and the ship ship got away.
On 9 May 1943, Wahoo proceeded up the coast with the intention of closing Kone Saki. Radar 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.
Wahoo cleared the area to the northeast to patrol the Tokyoo - Paramushiro route and continued her patrol; on 12 May, she sighted two freighters. She fired four torpedoes from 1200 yards (1100m); only one hit. Then Wahoo fired her last two torpedoes. Nothing was seen of the first. The second hit under the bridge with a dull thud, much louder than the duds heard only on sonar but lacking the "whacking" noise which accompanies a wholehearted explosion. The other freighter opened fire with heavy guns and charged Wahoo. The submarine was helpless to stop the two ships.
Wahoo cleared the area to the east and set a course for Pearl Harbor and arrived 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.
On May 23, the submarine departed for Mare Naval Ship Yard, and she arrived six days later to commence overhaul. From 11 July to 20 July the submarine underwent intensive post-repair trials and training. On 20 July, squadron commander Captain John B. Griggs, Jr., came aboard and made presentations of awards. The following day, Wahoo departed for Pearl Harbor, arriving on July 27, 1943.
Sixth Patrol (August 1943)
She arrived in the Sea of Japan the following day and sighted three medium freighters headed south. The submarine fired one torpedo 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 surfaced tracking of the new target and dove for a submerged approach. Wahoo fired one torpedo; it hit at the point of aim but was a dud. She fired two more torpedoes. 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 Otori-class 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. She fired one torpedo at a medium-sized freighter. It missed. The next day, the scene was repeated with the same results. Wahoo sighted freighter heading north in ballast and commenced a submerged approach. Wahoo fired one torpedo which missed. Just as she 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.
Within four days, twelve Japanese vessels were sighted; nine were hunted down and attacked to no avail. Ten torpedoes broached, made erratic runs, or were duds. In light of the poor torpedo performance, ComSubPac ordered Wahoo to return to base.
On August 19, the submarine sighted a ship and commenced tracking. However, she withheld fire when she recognized the flag as Soviet. 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 20mm and 4" 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 them 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 on 29 August.
Seventh Patrol (October 1943)
Departed from Pearl Harbor to patrol and resupplied at Midway, then proceeded to the Sea of Japan, armed with the new Mark XVIII electric torpedos to operate in the La Perouse Strait. The plan was to enter the Sea of Japan first, on or about 20 September, with Sawfish 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 home. She was instructed to report by radio after she passed through the Kurils. Nothing further was ever heard from Wahoo.
In July 2008, a Russian dive team “Iskra” was searching for Russian Submarine L-19. At the request of Wahoo Project Group, they diverted from their normal routes to scan two sites which were thought to be probable locations for Wahoo. The first site was a freighter, the second site was a submarine recorded on their slide scan sonar. Divers then dove the the wreck on July 28-29, 2006 and Vladimir Kartashev took photos. On October 31, 2006 the US Navy confirmed the Wahoo had been found in a news release.