(KS type RO-109 scanned from "Submarines of the Imperial Japanese Navy" by Polmar and Carpenter)

IJN Submarine RO-109:
Tabular Record of Movement

© 2001-2016 Bob Hackett & Sander Kingsepp
Revision 3

20 April 1942:
Kobe. Laid down at Kawasaki Jukogyo K.K. as a 525-ton Kaisho (KS) Type submarine No. 400.

20 August 1942:
Numbered RO-109 and provisionally attached to Maizuru Naval District.

26 October 1942:
Launched as RO-109.

16 March 1943:
Lt (later LtCdr) Uesugi Kazuaki (63)(former torpedo officer of I-171) is appointed the Chief Equipping Officer (CEO).

30 April 1943:
Completed and attached to Sasebo Naval District. Lt Uesugi is the CO. Assigned to SubRon 11 for training.

14 August 1943:
Departs Sasebo for Rabaul.

15 August 1943:
Reassigned to Rear Admiral (later Vice Admiral) Harada Kaku's (former CO of CVS CHIYODA) SubRon 7.

24 August 1943:
Arrives at Rabaul.

1 September 1943:
Reassigned to SubRon 7's SubDiv 51, Eighth Fleet.

9 September 1943:
Departs Rabaul to patrol S of Guadalcanal on her first war patrol.

25 September 1943: Operation "SE-Go" - The Evacuation of Kolombangara, Guadalcanal:
The Japanese begin the evacuation of the garrison on Kolombangara by assault boats and barges.

2 October 1943:
Returns to Rabaul.

13 October 1943:
Departs Rabaul on her first supply run to Sarmi, New Guinea.

14 October 1943:
Arrives at Sarmi, unloads her cargo, then departs.

15-16 October 1943:
Redirected for lifeguard duty to pick up downed Mitsubishi G4M "Betty" crew, but fails to locate any survivors. Redirected to the Lae, New Guinea area.

19 October 1943:
RO-109 is detected and chased by USS REID (DD-369) and PERKINS (DD-377). PERKINS also depth-charges the submarine without damaging it. Lt Uesugi fires a spread of torpedoes at USS DRAYTON (DD-366), but misses.

31 October 1943:
Returns to Rabaul.

8 November 1943:
Departs Rabaul for her second war patrol to the Bougainville area.

24 November 1943:
Returns to Rabaul.

3 December 1943:
Departs Rabaul for her third war patrol to the Bougainville area.

9 December 1943:
Returns to Rabaul.

13 December 1943:
Departs Rabaul on her first supply run to Buin, New Guinea.

16 December 1943:
Arrives at Buin, unloads her cargo, then departs.

19 December 1943:
Returns to Rabaul.

23 December 1943:
Departs Rabaul on her second supply run to Buin.

26 December 1943:
Arrives at Buin, unloads her cargo, then departs.

30 December 1943:
Returns to Rabaul.

24 January 1944:
Departs Rabaul on her third supply run to Buin.

28 January 1944:
Arrives at Buin, unloads her cargo, then departs.

31 January 1944:
Returns to Rabaul.

7 February 1944:
Departs Rabaul on her second supply run to Sarmi.

9 February 1944:
Arrives at Sarmi, unloads her cargo, then departs.

11 February 1944:
Returns to Rabaul.

20 February 1944:
Departs Rabaul for Truk via New Hanover Island.

25 February 1944:
Arrives at Truk.

26 February 1944:
Departs Truk for Sasebo.

3 March 1944:
Arrives at Saipan, departs on the same day.

11 March 1944:
Arrives at Sasebo for repairs.

20 March 1944:
Lt (later LtCdr) Sugayoshi Tessho (65)(former CO of RO-68) is appointed the CO. [1]

13 April 1944:
Departs Sasebo for Saipan.

20 April 1944:
Arrives at Saipan.

22 April 1944:
Departs Saipan to patrol N of New Guinea on her fourth war patrol.

29 April 1944:
Joins patrol unit "B" SE of Mereyon Islet.

8 May 1944:
Returns to Saipan.

16 May 1944:
RO-109 departs Saipan on her fifth war patrol to form a picket line with RO-104, RO-105, RO-106, RO-108, RO-112 and RO-116 to warn of American invasion forces approaching the Palaus.

18 May 1944:
The U.S. Navy intercepts radio traffic indicating that the Japanese have established a new submarine picket "NA line" between Truk and the Admiralty Islands to intercept American carriers. LtCdr Walton B. Pendelton's USS ENGLAND (DE-635) departs from the Solomons with RABY (DE-698) and GEORGE (DE-697) as a hunter-killer group to attack the NA line.

27 May 1944:
The Sixth Fleet decodes American signals that indicate that several submarines of the NA line have been sunk. The Japanese flash a warning message. Lt Sugamasa moves RO-109 to a new position 60 miles NW of his original position.

31 May 1944:
Departs the patrol area.

5 June 1944:
Arrives at Truk.

12 June 1944:
Departs Truk to patrol in the vicinity of Truk on her sixth war patrol.

16 June 1944:
Joins patrol unit "D".

22 June 1944:
Departs the patrol area.

28 June 1944:
Returns to Truk.

16 July 1944:
Arrives at Sasebo for repairs and overhaul.

5 August 1944:
LtCdr (later Captain, JMSDF) Oba Saichi (62)(former CO of RO-49) is appointed the CO.

15 August 1944:
SubDiv 51 is disbanded. RO-109 and RO-112 are reassigned to Kure SubRon to serve as training vessels.

5 September 1944:
Lt (LtCdr, posthumously) Yuchi Atsushi (66)(former torpedo officer of RO-49) is appointed the CO.

25 September 1944:
Reassigned to the Kure SubRon's SubDiv 33.

13 October 1944: Operation "SHO-I-GO" - The Defense of the Philippines:
Admiral Toyoda Soemu, CINC, Combined Fleet, orders the SHO-I-GO plan activated.

14 October 1944:
Lt (promoted LtCdr 1 November; Cdr, posthumously) Masuzawa Seiji (65)(former CO of I-158) is appointed the CO.

17 October 1944:
RO-109 is directly attached to Combined Fleet HQ.

20 October 1944: American Operation "KING TWO" - The Invasion of Leyte, Philippines:
Admiral (later Fleet Admiral) William F. Halsey's Third Fleet of 738 ships including 18 aircraft carriers, six battleships, 17 cruisers, 64 destroyers and over 600 support ships land the Army's X Corps (24th Infantry and 1st Cavalry Divisions) and the XXIV Corps (7th, 77th and 96th Infantry Divisions) that begins the campaign to retake Leyte.

That same day, RO-109 is reassigned to SubDiv 34, Sixth Fleet.

25 October 1944:
Reassigned to patrol unit "C". Departs Kure for the Lamon Bay area on her seventh war patrol.

3 November 1944:
140 miles NNE of Manila. While recharging batteries on the surface at 0700 (JST), RO-109 spots an unidentified Allied submarine and commences an approach, but the adversary crash-dives before any torpedoes are launched.

10 November 1944:
Departs her patrol area.

19 November 1944:
Arrives at Sasebo for repairs and overhaul.

18 December 1944:
Departs Sasebo on her eighth war patrol for an area E of the Philippines.

23 December 1944:
490 nms E of Cape Eluanbi, Taiwan. At 1420, RO-109's sonar operator picks up an enemy task force and tracks it for a while, but the submarine fails to reach the firing position.

5 January 1945:
330 nms SE of Cape Eluanbi. RO-109's sonarman again picks up suspicious noises, this time evidently belonging to an enemy convoy.

9 January 1945: American Operation "MIKE ONE" - The Invasion of Luzon at Lingayen Gulf, Philippines:
Vice Admiral (later Admiral) Thomas C. Kinkaid's Task Force 77 lands almost 175,000 men of General Walter Krueger's Sixth Army under cover of heavy gunfire from Vice Admiral (later Admiral) Jesse B. Oldendorf's TG 77.2 bombardment force and aircraft of Rear Admiral (later Vice Admiral) Calvin T. Durgin's TG 77.4. In a five-month campaign, the Sixth Army defeats LtGen Yamashita Tomoyuki's 14th Army Group's defenders.

12 January 1945:
Returns to Sasebo.

3 February 1945:
Departs Sasebo for an area W of Luzon.

16 February 1945:
60 miles W of Lingayen Gulf. At 1800, LtCdr Masuzawa sights one battleship and two cruisers protected by a screen of destroyers, heading north.

17 February 1945:
LtCdr Masuzawa attacks an enemy task force in the same area but scores no hits.

2 March 1945:
Returns to Kure, later transferred to Sasebo for repairs and overhaul.

17 March 1945:
Lt (LtCdr, posthumously) Nakagawa Hiroshi (68)(former CO of RO-58) is appointed Commanding Officer.

26 March 1945: American Operation "ICEBERG" - The Invasion of Okinawa:
The 77th Infantry Division lands on the Kerama Retto and captures advance bases and anchorages.

1 April 1945:
Vice Admiral (later Admiral) Raymond A. Spruance's Fifth Fleet, including more than 40 aircraft carriers, 18 battleships, 200 destroyers and over 1,000 support ships surround Okinawa. LtGen Simon B. Buckner Jr's (KIA) U.S. Tenth Army (7th, 77th, 96th Infantry, 2nd, 6th Marine divisions) makes amphibious landings and takes the island from LtGen Ushijima Mitsuru's 32nd Army.

12 April 1945:
at 1400, RO-109 departs Sasebo on her tenth war patrol for an area S of Okinawa. She makes an overnight stop in Terashima Strait, west of Sasebo, until the final departure at 1000 on the 13th. She is scheduled to arrive in an area 20 miles S of Okinawa by 20 April, but there are no further contacts after her departure.

25 April 1945:
165 nm SSW of Okino-Daito Jima. LtCdr F. W. Kuhn's fast transport USS HORACE A. BASS (APD-124) is escorting a 17-ship convoy from Guam to Okinawa, when at 1804, a sonar contact is made at 1,250 yards. BASS drops five depth charges at the submarine (probably RO-109), that commences a series of evasive maneuvers, attempting to jam its attacker's sonar with bursts of carefully tuned sound impulses. Following the DC detonations, contact is lost.

Sound contact is regained at about 900 yards. BASS makes another attack with five depth charges, but the submarine evades it, diving deeper. Several successive attacks also fail, since the submarine seems to make use of German Bold-type sonar decoys (SBT), creating multiple false targets.

Shortly before 2000, following the attack with six last depth charges, debris and oil surface at 21-58N, 129-38E. BASS is then ordered to abandon the chase and rejoin the convoy.

7 May 1945:
Presumed lost with all 65 hands off Okinawa.

10 June 1945:
Removed from the Navy List.

Authors' Note:
[1] Sugayoshi Tessho's name appears in older sources as Sugamasa Tetsuaki.

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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