© 2001-2002 Bob Hackett & Sander Kingsepp
Revision 3
31 March 1927: 9 March 1928: 1 June 1938: 1 May 1941: November 1941: 1 December 1941: 2 December 1941: 6 December 1941: Operation "M" - The Attack on the Southern
Philippines: 7 December 1941: 9 January 1942: Operation "H" - The Invasion of the Celebes: 11 January 1942: 12 January 1942: 18 January 1942: 30 January 1942: 1 February 1942: 9 February 1942: 19 February 1942: The Attack on Darwin: 16 March 1942: 21 March 1942: April 1942: Operation "MI": The Battle of Midway: 2 April 1942: 26 May 1942: 1 June 1942: 6 June 1942: June 1942: 14 July 1942: 16 July 1942: 4 August 1942: 7 August 1942 - American Operation "Watchtower" - The Invasion of
Guadalcanal, Solomons: That day, the I-121 and the I-122 depart Rabaul to shell and reconnoiter Guadalcanal and Tulagi.
Completed at Kawasaki, Kobe, commissioned in the IJN as
the I-21 and based in the Kure Naval District.
The I-21 is conducting speed trials off Yokosuka Bay. About
1100, the I-21 collides with the destroyer SHIOKAZE that is on torpedo launch
trials. Both ships suffer light damage with no casualties. The I-21 returns to
Yokosuka to repair her bow that is bent 60 degrees to starboard.
The I-21 is renumbered as the I-121.
The I-121 is assigned to the Third Fleet in Rear Admiral Kono
Chimaki’s SubRon 6 under Captain Miyazaki Takeji’s (former of RO-57, I-122, I-1)
SubDiv 13 with the I-122.
The I-121, under LtCdr Endo Shinobu, departs Yokosuka for
Samah, Hainan Island, China.
Departs Samah.
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). Mt. Niitaka, located in Formosa (now
Taiwan), is then the highest point in the Japanese Empire.
Vice Admiral Takahashi Ibo's (former CO of KIRISHIMA) Second
Fleet, Southern Force, Philippines Seizure Force departs Palau.
The I-121 and I-122 lay a minefield NE of Singapore. The
I-121 lays 42 Type 88 mines.
Vice Admiral Takahashi's
force invades Legaspi covered by the light carrier RYUJO, CruDiv 5's HAGURO,
MYOKO, NACHI, DesRon 2's light cruiser JINTSU and nine destroyers and Rear
Admiral Kubo's (former CO of MIKUMA) seaplane tenders CHITOSE, MIZUHO, light
cruisers NAKA, NAGARA, five destroyers and seven transports.
19-20 December 1941:
Takahashi's force invades Davao, Philippines.
24 December 1941:
Takahashi's force invades Jolo, Philippines.
31 December 1941:
The I-121 and the I-22 arrive at Davao. They are
joined there by SubRon 6's flagship, the 6,600-ton submarine tender CHOGEI and
the I-123 and I-124.
5 January 1942:
SubRon 6's I-121, -122, -123 and the I-124's
operational area is the Flores Sea and the Torres Strait N of Australia. SubRon
6 departs Davao to reconnoiter the Port Darwin area, northern Australia.
Vice Admiral
Takahashi's Netherlands East Indies Force lands invasion forces on Mendado and
Kema (11 January), Kendari (24 January), Ambon (30 January) and Makassar (9
February).
125 miles SW of Darwin. The I-121 is in the shallow
waters of Joseph Bonaparte Gulf.
N Australia. The I-121 lays 39 mines in the Clarence
Strait that connects the Van Diemen Gulf and the Timor Sea at the approaches to
Port Darwin, the U.S. Asiatic Fleet's main logistics base.
The I-124 sights the USS HOUSTON (CA-30) and two destroyers but is
unable to attack.
Indian Ocean. The I-121 fires three torpedoes at an
unidentified 10,000-ton ship, but misses.
After the loss of the I-124, SubRon 6's I-121 and the
I-122 arrive at Davao, Philippines. They are serviced by the tender CHOGEI. The
I-121's damaged fuel tanks are repaired.
LtCdr Fujimori Yasuo (former CO of RO-60) assumes
command. SubRon 6's mission is to protect the shipping route between Davao and
Kendari, Celebes from American submarines.
The I-123
arrives at Davao from Australia.
SubRon 6's operational area is in the Flores Sea and the
Torres Strait N of Australia. The I-121 and the I-122 depart Davao. The I-121 is
to act as a weather ship in the Arafura Sea. She patrols 300 miles NE of
Morotai.
The I-122 detaches and proceeds SE. The I-121
continues south.
16 February 1942:
50 miles NW of Darwin, Australia. The I-121 is on
station. 18 February 1942:
The I-21 surfaces on station prior to sunset to
recharge her batteries, but is strafed by an Australian patrol plane. Fujimori
crash-dives. After dark he resurfaces and at 2030 sends a weather report that is
relayed to Vice Admiral (Admiral, posthumously) Nagumo Chuichi's Carrier Strike
Force then enroute from Palau.
At 0230 Fujimori sends a second
weather report. At 0957 (local), Nagumo's Striking Force raids Port Darwin.
Seventy-one "Kate" attack planes, 81 "Val" dive-bombers and 36 "Zeke" fighters
led by Cdr (later Captain) Fuchida Minoru (of Pearl Harbor) from CarDiv 1's
AKAGI, and the KAGA and CarDiv 2's HIRYU and the SORYU attack Darwin. They
destroy 15 aircraft including nine American Curtiss P-40 "Kittyhawk" fighters,
sink eight ships including the destroyer USS PEARY (DD-226) and the large Army
transport GENERAL M.C. MEIGS, damage nine ships including the seaplane tender
(WW1 destroyer conversion) USS WILLIAM B. PRESTON (AVD-7). The carrier strike is
followed by a strike of 28 twin engine land-based Mitsubishi G3M2 "Nells" of the
1st Kokutai from Ambon and 27 Mitsubishi G4M1 "Bettys" of the Kanoya Kokutai
based at Kendari on Sulawesi, Celebes.
The I-21
departs from her station.
28 February 1942:
The I-121 arrives at Staring (Teluk) Bay, near Kendari and refuels.
SubRon 6's boats are serviced by the CHOGEI that arrived earlier from Davao.
9 March 1942:
The I-121, I-122, I-123 depart Staring Bay for Japan
accompanied by the CHOGEI.
Vice Admiral, the Marquis, Komatsu Teruhisa (former CO of
CA NACHI) assumes command of the Sixth Fleet (Submarines).
The I-121’s minelaying equipment malfunctions. She returns
to Kure for repairs.
The I-121 is in Vice
Admiral’s Advance Expeditionary Force (Sixth Fleet) with SubDiv 13's I-122 and
the I-123. SubDiv 13 is assigned to carry gas and oil to Lisianski Island and
French Frigate Shoal, Hawaii. The K-2 operation plan calls for two H8K "Emily"
flying boats to refuel at the Shoal and then reconnoiter the naval base at Pearl
Harbor prior to the Midway Invasion.
Departs Japan with a cargo of aviation gasoline and oil and
proceeds via Kwajalein, Marshall Islands for the French Frigate Shoal.
SubDiv 13 completes its repairs and departs Yokosuka.
20 May 1942:
SubDiv 13 arrives at Kwajalein.
The I-121 arrives at the Shoal. LtCdr Fujimori observes an
enemy seaplane tender in the lagoon as well as patrol planes in the area. That
night, Fujimori surfaces and radios his sightings to the Sixth Fleet at
Kwajalein. The Pearl Harbor reconnaissance is cancelled. Thereafter, the I-123,
I-121, I-122 are ordered to patrol the area of Laysan Island and French Frigate
Shoal.
Departs French Frigate Shoals and heads west.
The I-121, I-122 and the I-123 begin patrolling off the Hawaiian
Islands.
SW of Lisianski Island. LtCdr Fujimori sights an American
submarine heading NE. Since the I-121 has no torpedoes, he cannot attack.
Returns to Yokosuka.
The I-121 is reassigned with the I-122 and the I-123 to the
Eighth Fleet at Rabaul in Rear Admiral Yoshitomi’s Setsuzo’s SubRon 7, under
Captain Miyazaki’s SubDiv 13.
Departs Yokosuka.
Arrives at Rabaul.
Rear Admiral (later Admiral) Richmond K. Turner's Amphibious Task Force 62, covered by Vice Admiral (later Admiral) Frank J. Fletcher's Task Force 61 and Rear Admiral (later Admiral) John S. McCain's Task Force 63's land-based aircraft, lands Maj Gen (later General/MOH/Commandant) Alexander A. Vandegrift's 1st Marine Division on Florida, Tulagi, Gavutu, Tanambogo and Guadalcanal opening a campaign to take the island.
30 miles S of Cape St. George, New Ireland. Lookouts aboard LtCdr H. G. Munson's USS S-38 spot the I-121 enroute on the surface from Rabaul to Savo Island, but Munson is unable to attack.
22 August 1942:
SE of San Cristobal. The I-121 fires torpedoes at
warships in Task Force 16, but misses. Lookouts on the USS PORTLAND (CA-33) spot their wake.
24 August 1942: The Battle of the Eastern Solomons:
Vice Admiral (later
Admiral) Frank J. Fletcher’s Task Force 61: USS SARATOGA (CV-3) and the
ENTERPRISE (CV-6) launches aircraft that find and sink the light carrier RYUJO.
In turn, CarDiv 1’s SHOKAKU and the ZUIKAKU launch aircraft that find and damage
the ENTERPRISE. That evening, aircraft from the SARATOGA damage the seaplane
carrier CHITOSE.
175 miles SW of San Cristobal Island, Solomons. The 1-121 is spotted on the surface by American patrol planes and attacked. Slow to dive, her stern is damaged by bombs or depth charges. She ships water, but is able to trim and proceeds towards Guadalcanal.
25 August 1942:
150 NE miles SW of San Cristobal. LtCdr Fujimori sights
an American carrier of the SARATOGA-class launching planes 5 miles to the north
heading east. The carrier is screened by four destroyers. Fujimori is unable to
position the I-121 for an attack.
8 September 1942:
Departs Rabaul.
20 September 1942:
Returns to Kure for an overhaul.
1 December 1942:
Departs Kure.
21 December 1942:
Returns to Rabaul.
23 December 1942:
Departs Rabaul to participate in supply missions to New
Guinea.
29 January 1943:
Departs Rabaul to support the evacuation of troops from
Guadalcanal.
31 January 1943: Operation "KE-Go" - The Evacuation of Guadalcanal:
A
task force of units of the Second and Third Fleets from Truk including the
carriers ZUIKAKU, ZUIHO, JUNYO, Bat Div 3: KONGO, HARUNA, CruDiv 4: ATAGO,
TAKAO, CruDiv 5: HAGURO, MYOKO, DesRon 4's light cruiser NAGARA, DesRon 10's
light cruiser AGANO and destroyers steams north of the Solomons as a feint to
cover Rear Admiral (later Vice Admiral) Hashimoto Shintaro's (former CO of
HYUGA) destroyer force from Rabaul.
9 February 1943: Operation "KE-Go":
The Japanese complete the successful
evacuation of 11,700 troops from Guadalcanal.
14 February 1943:
Departs Rabaul.
5 March 1943:
Returns to Kure.
25 April 1943:
Departs Kure.
7 May 1943:
Arrives at Rabaul.
10 May - August 1943:
Makes eight supply runs from Rabaul to Lae, New
Guinea.
19 August 1943:
Departs Rabaul.
1 September 1943:
Returns to Kure. The I-121 and I-122 are withdrawn from
combat and assigned to training duties at the Kure Naval Base thereafter.
1 January 1944:
The I-121 is in the Kure SubRon’s SubDiv 18 with the
I-122 and the I-153, -154 and the I-155. Continues training duties.
12 June 1945:
Transferred to the Maizuru Naval Base, Honshu in the Kure
SubRon’s SubDiv 33. Remains there until the end of the war.
15 August 1945:
The Emperor Hirohito (Showa) broadcasts an Imperial
Rescript that calls for an end to hostilities.
September 1945:
The I-121 surrenders at Maizuru.
13 October 1945:
At Maizuru with the I-201 and the I-202.
30 November 1945:
Removed from the Navy List.
30 April 1946:
Scuttled in Wakasa Bay.
