IJN Submarine RO-44:
Tabular Record of Movement

© 2001-2017 Bob Hackett & Sander Kingsepp
Revision 2

14 February 1942:
Tamano. Laid down at at Mitsui Zosensho as a 960-ton type K6 submarine.

1 November 1942:
Numbered RO-44 and provisionally attached to Maizuru Naval District.

11 November 1942:
Launched as RO-44.

25 July 1943:
LtCdr (later Cdr) Hashimoto Mochitsura (59)(former CO of I-158) is appointed the Chief Equipping Officer (CEO). [1]

13 September 1943:
Completed and attached to Maizuru Naval District. Assigned to Rear Admiral Ishizaki Noboru's (42)(former CO of HYUGA) SubRon 11 for working-up. LtCdr Hashimoto Mochitsura is the Commanding Officer.

13-14 November 1943:
Ise Bay. RO-44 conducts tests with an aircraft search radar borrowed from the Kure Naval Air Station. SubRon 11 reports the results of the tests, but is rebuffed for conducting tests without the approval of the Navy Technical Department.

November 1943:
Departs Kure for the Maizuru Navy Base.

25 December 1943:
RO-44 is reassigned to Captain (Rear Admiral, posthumously) Shimizu Taro's (48) SubDiv 34 in Vice Admiral (Admiral, posthumously) Takagi Takeo's (39)(former CO of MUTSU), Sixth Fleet.

28 December 1944:
Departs Maizuru for Truk.

6 January 1944:
Arrives at Truk.

12 January 1944:
Truk. HEIAN MARU transfers stores to RO-44.

15 January 1944:
Departs Truk on her first war patrol to Espiritu Santo area. No contacts with the enemy are made.

27 January 1944:
Truk-Guam shipping lanes. Lookouts on Cdr (later Captain) Robert E. Dornin's (USNA '35) USS TRIGGER (SS-237) sight the conning tower of an RO-class submarine - probably RO-44 - dead ahead. Dornin sets up to fire a bow shot from 800 yards. He comes to periscope depth and sees the Japanese submarine, now less than 100 yards away, is preparing to attack.

Expecting an incoming torpedo, Dornin takes TRIGGER to 150 feet, but his soundman hears no torpedo noises. Dornin comes back up to periscope depth and sees the Japanese's periscope. When he next returns to periscope depth, the RO-boat has disappeared. [2]

31 January 1944: American Operation "FLINTLOCK" - The Invasion of the Marshalls:
Task Force 58 lands the 4th Marine Division and the Army's 7th Infantry Division. They capture the Kwajalein, Roi-Namur and Majuro atolls.

17-18 February 1944: American Operation "HAILSTONE" - The Attack on Truk:
Task Force 58's five fleet carriers and four light carriers, supported by six battleships, ten cruisers and 28 destroyers, launch air attacks on Japanese ships in the lagoon, airfields and shore installations. They sink 31 transports and 10 naval vessels (two cruisers, four destroyers and four auxiliary vessels), destroy nearly 200 aircraft and damage severely about 100 more.

During the attacks, RO-44 returns to Truk from the Espiritu Santo area. She is ordered to take a holding position 40 miles NE of Truk to intercept the enemy carriers.

18-21 February 1944: American Operation "CATCHPOLE" - The Invasion of Eniwetok:
The V Amphibious Corps Reserve (Marine 22nd Regiment and the Army's 106th Infantry Regiment) capture Engebi Island, Eniwetok and Parry atolls.

February 1944:
After passing Jaluit, RO-44 approaches Mili, but sights an American battleship and two aircraft carriers. LtCdr Hashimoto cannot gain attack position due to the American's superior speed.

21 February 1944:
Returns to Truk.

28 February 1944:
Departs Truk for Mili carrying cargo of food, ammunition and a set of new code books.

1 March 1944:
Soon after departure the clamps securing the rubber containers on the afterdeck give way and the whole shipment is washed overboard. LtCdr Hashimoto heads back to Truk.

2 March 1944:
Departs Truk on a new supply run to Mili, carrying a total of 11-tons of food and ammunition. RO-44 is also ordered to reconnoiter Majuro Island on her way back to Truk.

9 March 1944:
After passing Jaluit, RO-44 approaches Mili from the west and sights a task force comprising two carriers, a battleship and a cruiser, all heading SE. At 0545 (JST), LtCdr Hashimoto commences an approach for a four-torpedo salvo, although the distance is too far. He surfaces and chases the task force for about an hour. Suddenly, six destroyers appear and force RO-44 to dive.

11 March 1944:
Arrives at Mili. At night, the cargo is disembarked. Departs Mili, carrying 17 passengers.

13 March 1944:
At dawn, when RO-44 is conducting periscopic reconnaissance, a line of red and white lights is sighted.

About 2300, while approaching Majuro, a red light is sighted ahead. RO-44 crash-dives. At periscope depth, the number of lights increases as the submarine gets closer to the atoll. LtCdr Hashimoto believes the lights he sees are on an enemy airfield.

14 March 1944:
By 0330, the lights are seen to be coming from American warships - an aircraft carrier, eight battleships and tank landing craft. The nearest battleship is only 500 yards away! Hashimoto decides not to endanger his supply mission by attacking. Instead, he reconnoiters Majuro and reports his sightings to Headquarters, Combined Fleet: "The Majuro anchorage is full of battleships and other capital ships”.

29 March 1944:
Returns to Truk.

11 April 1944:
Departs Truk for a position S of the island.

15 April 1944:
Returns to Truk.

17 April 1944:
B-24 "Liberators" raid Truk. RO-44 and RO-42 dive, but receive minor damage by near misses underwater.

20 April 1944:
Truk is bombed again. RO-44 and other submarines submerge to the bottom of the shallow 75 foot deep anchorage, but when LtCdr Hashimoto surfaces he finds his periscope has been damaged in the raid. It can only be repaired in Japan.

RO-44 departs Truk via Saipan for Kure. Enroute, she is bombed and strafed by an American aircraft, but only damaged slightly by machine-gun bullets.

29 April 1944:
Arrives at Kure for repairs and overhaul.

14 May 1944:
Lt (LtCdr, posthumously) Uesugi Sadao (65)(former torpedo officer of RO-500) is appointed the CO.

That same day, RO-44 departs Kure for Saipan.

20 May 1944:
Arrives at Saipan.

23 May 1944:
Departs Saipan to reconnoiter Eniwetok, Marshall Islands.

11 June 1944:
Lt Uesugi reports about his observation results and heads for the area NE of Eniwetok.

13 June 1944:
Carries out a periscope observation of Brown Island, Eniwetok. Receives an order to proceed to the Marianas area at flank speed.

15 June 1944: American Operation "FORAGER" - The Invasion of Saipan:
Vice Admiral (later Admiral) Richmond K. Turner's (USNA '08) (former CO of ASTORIA, CA-34) Task Force 52 lands Marine LtGen Holland M. Smith's V Amphibious Corps and the invasion begins. That day, LtCdr Uesugi reports the results of his reconnoitering of Brown, then proceeds towards Saipan. RO-44 is MIA thereafter.

16 June 1944:
110 miles E of Eniwetok. LtCdr E. B. Fay's USS BURDEN R. HASTINGS (DE-19) makes radar contact with a surfaced submarine. She closes and challenges with her Aldis lamp, but there is no reply and the submarine crash-dives.

LtCdr Fay fires two barrages of twenty-four Mark 10 "Hedgehog" ahead-thrown projector charges and drops four depth charges that sink the submarine at 11-13N, 164-15E. At daybreak, an aluminum plaque with "RO-44" on it is recovered from the debris.

That same day, RO-44 is ordered to assume a position SE of the Marianas.

12 July 1944:
Presumed lost with all 72 hands off Saipan. Lt Uesugi is promoted LtCdr posthumously.

10 August 1944:
Removed from the Navy List.

Authors' Note:
[1] Cdr Hashimoto's first name is misspelt as "Iko" in several postwar sources.

A review of all RO-class TROMs indicates that RO-44 likely was the unidentified RO-boat.

Thanks go to Dr. Higuchi Tatsuhiro of Japan. Special thanks for assistance in researching the IJN officers mentioned in this TROM go to Mr. Jean-François Masson of Canada.

– Bob Hackett and Sander Kingsepp

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