(Type KD6 submarine - colorized photo by Irootoko Jr)

IJN Submarine I-171: Tabular Record of Movement

2001-2010 Bob Hackett & Sander Kingsepp

Revision 3

24 December 1935:
I-71 is completed at Kawasaki Kobe Yard, commissioned in the IJN and based in the Kure Naval District.

11 November 1941:
I-71 is in SubRon 3's SubDiv 20 in the Sixth Fleet. LtCdr Kawasaki Michio is the Commanding Officer. Departs Saeki with I-68, I-69, I70, I-72 and I-73.

20 November 1941:
Arrives at Kwajalein.

23 November 1941:
Departs Kwajalein.

2 December 1941:
The coded signal "Niitakayama nobore (Climb Mt. Niitaka) 1208" is received from the Combined Fleet. It signifies that hostilities will commence on 8 December (Japan time). [1]

5 December 1941:
I-71 reconnoiters off the Hawaiian Islands in the Alalakeiki Channel between Maui and Kahoolawe. Later, I-71 and I-73 reconnoiter the Lahaina anchorage.

7 December 1941: The Attack on Pearl Harbor:
SubRon 3 is deployed south of Oahu. Its mission is to reconnoiter and attack any ships that try to sortie from Pearl Harbor. I-71 is assigned to patrol from 25 to 50 miles south of Oahu with I-8, I-68, I-69, I-70, I-72, I-73, I-74 and I-75. During this mission in December, I-71 is subjected to several depth-charge attacks.

21 December 1941:
After dark, I-71 surfaces off Johnston Island and attempts to shell it, but fire is returned and she dives again.

28 December 1941:
Returns to Kwajalein with I-68 and I-72.

12 January 1942:
Departs Kwajalein, on her second war patrol, with I-72 and I-73 to relieve I-18, I-22 and I-24 that form a picket line in the Hawaii area.

29 January 1942:
Hawaiian Islands. During the evening, I-71 attacks a three ship convoy bound from Kahului, Maui for Hilo, Hawaii that includes 622-ton Army transport GENERAL ROYAL T. FRANK carrying army recruits and small freighter KALAE with a barge in tow. Both ships are being escorted by an old flush-deck destroyer. I-71 torpedoes FRANK. She explodes and sinks in 30 seconds in the Alenuihaha Channel about two miles W of Maui.

1 February 1942:
Vice Admiral (later Fleet Admiral) William F. Halsey Jr's (former CO of SARATOGA, CV-3) Task Force 8's USS ENTERPRISE (CV-6) raids Kwajalein and Wotje in the Marshall Islands. Douglas SBD "Dauntless" dive-bombers of VB-6 and VS-6 and TBD "Devastators" of VT-6 sink a transport and damage light cruiser KATORI, flagship of the Sixth Fleet's (Submarines) Commander, Vice Admiral Shimizu Mitsumi (former CO of ISE). Shimizu is wounded. I-23, submarine depot ship YASUKUNI MARU and several other important ships are also damaged in the raid.

16 February 1942:
Arrives at Kwajalein.

18 February 1942:
Departs Kwajalein with I-72.

20 February 1942:
Vice Admiral Wilson Brown Jr.'s (later President Roosevelt's Naval Aide) Task Force 11's USS LEXINGTON, (CV-2) is en route to attack Rabaul, but is spotted by a Kawanishi H6K "Mavis" flying boat of the Yokohama Kokutai. Since surprise is lost, the American attack is cancelled. TF 11 is attacked off Bougainville by naval land-based bombers of the 4th Kokutai, but they are beaten off with heavy losses.

I-71 and I-72 are diverted E of Wake Island.

6 March 1942:
I-71 arrives at Kure.

15 April 1942:
Departs Kure to form a picket line.

16 March 1942:
Vice Admiral, the Marquis, Komatsu Teruhisa (former CO of CA NACHI) assumes command of the Sixth Fleet (Submarines). Vice Admiral Shimizu, wounded in the raid on Kwajalein, returns to Japan to convalesce.

20 March 1942:
SubDiv 20 is disbanded. I-71 is reassigned to SubDiv 12.

15 April 1942:
Departs Kure on her third war patrol with I-72 to form a picket line.

10 May 1942:
Arrives at Kwajalein.

20 May 1942:
I-71 is renumbered as I-171.

24 May 1942: Operation "K-2" - The second surprise raid on Pearl Harbor:
Prior to the Battle of Midway, I-171 departs Kwajalein to act as the radio beacon for Kawanishi H8K "Emily" flying boats east of the French Fregate Shoal.

May-June 1942: Operation "MI" - The Battle of Midway:
1-171 is in Rear Admiral Kono Chimaki's SubRon 3 with I-168, I-169, I-174 and I-175. She is part of a picket line formed in the Hawaii area. SubRon 3 is deployed between 20N, 166-20W and 23-30N, 166-20W.

20 June 1942:
Returns to Kwajalein with I-174 and I-175.

5 July 1942:
LtCdr Kobayshi Shigeo assumes command.

8 July 1942:
Departs Kwajalein to reconnoiter the Fiji-Samoa area on her fourth war patrol.

16 to 24 July 1942:
Fiji. LtCdr Kobayashi reports that there are no ships in Suva harbor, then heads for the Samoa area.

28 July 1942:
Reconnoiters Pago-Pago.

29 July 1942:
Off Tutuila, LtCdr Kobayashi sights and attacks an unidentified merchant, but misses with a torpedo.

12 August 1942:
Arrives at Truk.

17 August 1942:
Departs Truk.

24 August 1942:
Arrives at Kure for an overhaul.

18 September 1942:
Truk. I-171 is in Subron 3 with I-8, I-168, I-169, I-172, I-174 and I-175.

15 February 1943:
Departs Kure on a supply run to Kiska.

26 February 1943:
Arrives at Kiska.

2 March 1943:
Departs Kiska.

18 March 1943:
Arrives at Paramushiro, Kuriles.

20 March 1943:
Oiler TEIYO MARU refuels I-171, I-169 and I-31.

22 March 1943:
Departs Paramushiro on her fifth war patrol to form a picket line.

25 March 1943:
Takes up scouting line duties at 52-55N, 174 E.

6 April 1943:
Arrives at Yokosuka.

11 May 1943: American Operation "Landcrab" - The Invasion of Attu, Aleutians:
Rear Admiral (later Admiral) Thomas C. Kinkaid's Task Force 16, covered by Rear Admiral Francis W. Rockwell's Task Force 51, lands elements of the Army's 4th and 7th Infantry Divisions under the command of Maj Gen Eugene M. Landrum at Holtz Bay and Massacre Bay that later capture the island.

13 May 1943:
SubDiv 12 is reassigned to Northern Force.

21 May 1943: Operation "KE" - The Evacuation of Kiska:
The Imperial General Headquarters decides to evacuate the garrison at Kiska Island, Aleutians. That day, I-171 departs Yokosuka for Kiska on her sixth war patrol. En route, she is attacked by a patrol craft.

16 June 1943:
Arrives at Paramushiro. Oiler TEIYO MARU refuels I-171.

21 June 1943:
Vice Admiral (Admiral, posthumously) Takagi Takeo (former CO of MUTSU) assumes command of the Sixth Fleet (Submarines). Vice Admiral Komatsu is later appointed President of the Etajima Naval Academy.

26 June 1943:
Departs Paramushiro, on her seventh war patrol, with I-175 to raid enemy communications S of Amchitka, Aleutians.

3 August 1943:
Returns to Paramushiro.

5 August 1943:
Departs Paramushiro.

10 August 1943:
Arrives at Kure. SubDiv 12 is reassigned to SubRon 3.

30 August 1943:
LtCdr Shimada Takeo assumes command.

17 September 1943:
Departs Kure.

25 September 1943:
Arrives at Truk.

7 October 1943:
Departs Truk on her eighth war patrol, with ComSubDiv 12 embarked, to reconnoiter the area east of the New Hebrides.

19 October 1943
Vice Admiral Takagi orders ComSubDiv 12 aboard I-171 to assume temporary command over I-21 and I-32 to intercept six American fleet oilers that were sighted by I-36 off Hawaii. A Kawanishi H8K "Emily" flying boat of the 802nd NAG based at Jaluit fails to locate the oilers.

15 November 1943:
Returns to Truk.

17 December 1943:
Truk. HEIAN MARU transfers torpedoes to I-171.

22 December 1943:
Truk. HEIAN MARU transfers torpedoes to I-171 and stores to RO-42.

25 December 1943:
Truk. HEIAN MARU transfers torpedoes to I-171.

7 January 1944:
Truk. HEIAN MARU transfers torpedoes to I-171.

9 January 1944:
Departs Truk.

13 January 1944:
Arrives at Rabaul.

17 January 1944:
Departs Rabaul.

26 January 1944:
Arrives at Rabaul.

30 January 1944:
Departs Rabaul on a supply run to Buka, carrying rubber containers on her deck. I-171 is the second submarine (after the I-181) to supply Buka's garrison.

31 January 1944:
15 miles W of Buka Island. LtCdr E. K. McLaren's USS GUEST (DD-472) and LtCdr R. R. Pratt's HUDSON (DD-475) are covering the transports that land Marine raiders on Green Island.

1 February 1944:
GUEST and HUDSON pick up a surface contact on their SG radars at 3,500 yards. The submarine - probably I-171 - dives, but the destroyers reacquire her on sonar. Both destroyers make depth-charge runs that sink the I-171 at 05-37S, 154-14E.

That same day, the IJN posts LtCdr Takeuchi Yoshitake as the next CO of I-171 - a command that he never assumes.

5 February 1944:
At 1652, USN codebreakers intercept and decrypt a message that reads: I-171 departed Rabaul January 30th to engage in transportation operations to Buka but she had not arrived at Buka by February 5th at 1800 as scheduled. After 3rd, she was called a number of times but there is no response. We have no further information on her ----- personnel items------.

12 March 1944:
I-171 is presumed lost with all 91 hands off Buka.

14 March 1944:
At 0754, USN codebreakers intercept and decrypt a message from the Commander Southeastern Area Submarine Force that reads: I-171 departed Rabaul January 30, arrived Buka Feb. 2 [blurred number might be 1 or might be 2]. Completed unloading men and cargo and (continued on special transportation duties). Has not been heard from since February 1. According to report of naval force at Buka, an enemy destroyer was (sighted) to west of Buka that date. It is assumed that Captain and all hands died in battle. -----.

30 April 1944:
Removed from the Navy List.

Authors' Notes: [1] Mt. Niitaka, located in Formosa (now Taiwan), was then the highest point in the Japanese Empire.

Thanks go to Dr. Higuchi Tatsuhiro of Japan. Thanks also go to John Whitman of the USA for info on CNO intercepts of Japanese messages.

Bob Hackett and Sander Kingsepp.

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