This story caught my attention after knowing that there were TWO Nagato Class Battleships yet the fate of the Mutsu was never told in any history books I ve seen, it was as if she had never existed to some people, even if some files were saying the Mutsu existed and to some others she never even existed, so I started a personnal research in order to find out what had really happened to the Japanese Battleship Mutsu during the War in the Pacific and found this.
There had been a disaster with the Imperial Japanese Navy and an all-out cover up for obvious reasons since Japan was still at war in 1943.
About the Imperial Japanese Mutsu (or Nagato for that matter)
Specs
Displacement: 39 116 tonnes (38 500 tons)
Dimensions: 215.8m x 29m x 9m
Machinery: Quadruple Screws Turbines
Top Speed: 23 Knots
Main Armament: Twenty 140mm (5.5in), eight 406mm (16in) Guns
Launched: November 1919
Date of Profile: 1920
The Battleship Nagato survived WW2 only to be used as a Target Ship for the Nuclear tests in the Bikini Island in 1946.
While the Mutsu s (Nagato sister-ship) fate remained untold.
31 May 1943:
Returns to Hashirajima.
Following the landings on Guadalcanal by the US Marines and General Mac Arthur Forces going on the Offensive on New Guinea, North of Australia, the Imperial Japanese Navy task force despite their attempt to stop this to happen were beaten and the Japanese Warships still intacts were ordered back to Hashirajima Naval Base in Japan on May 31 1943, that included the Battleship Mutsu
On June 8 1943, she was midway from her trip to Hashirajima and the Suo-Oshima Islands about two-miles South-West of Hashirajima and was hosting 113 Flying cadets, possibly mostly Fighter Pilots in training and 40 Instructors of the Tsuchira Naval Air Group.
Captain Tsuruoka's FUSO (another Japanese Battleship, Kongo Class this time) is moored about 1,100 yards SW of MUTSU.
DesRon 11’s flagship, light cruiser TATSUTA and several of the
squadron’s newly commissioned destroyers are moored more distantly
south of Hashirajima.
1145: After lunch, MUTSU’s deck crew prepares to move to mooring buoy
No. 2 because NAGATO (Mutsu sister-ship) is expected to return at about 1300 from Kure
after being drydocked. There is heavy fog and visibility is down to 500
yards. MUTSU's magazines contain a full load of ammunition including
16.1-inch Type 3 "Sanshikidan" incendiary shells designed as
anti-aircraft rounds. Each shell weighs 2,064-lbs. and contains 1,200
submunitions. Each turret magazine contains 240 shells (120 per gun),
including 50 "sanshiki-dans."
1213: Suddenly, MUTSU’s No. 3 turret’s magazine explodes. Vice Admiral
Shimizu, Commander of the First Fleet, a few miles away aboard NAGATO
sees a brilliant white explosion. Shortly thereafter, he receives a
coded message from FUSO’s Captain Tsuruoka. It says: "MUTSU blew up!"
MUTSU breaks in two. The 535-ft forward section collapses to starboard,
sinks quickly and lies on the pagoda mast on the floor of the bay. The
147-ft stern section upends, but remains floating. FUSO immediately
launches two of her Vedette boats. Her crew rescues 353 survivors of
the 1,474 crewmembers aboard MUTSU. Only 13 of the visiting flying
cadets/instructors are among the survivors. The IJN can ill-afford the
loss of 140 instructors and pilot trainees, particularly after the
heavy losses sustained in April in Operation "I-GO" during the
reinforcement of the 11th Air Fleet at Rabaul. Later, destroyers
TAMANAMI and WAKATSUKI arrive, as do boats from TATSUTA and the cruiser
MOGAMI. An antisubmarine alert is put into effect immediately.
1430: NAGATO arrives after zigzagging through Hiroshima Bay (before Hiroshima got nuked). Later,
since no submarines are sighted, the alert is cancelled. Later, the
frequency of patrols by naval vessels and aircraft is increased in
Hiroshima Bay, the Iyo-nada and the Bungo and Kii Suido channels.
NAGATO moors about 3,000 yards off FUSO’s port beam and takes aboard
the survivors rescued by TATSUTA. All 39 wounded sailors are
transported by TAMANAMI to a secluded hospital on Mitsukoshima. [1] A
major cover-up is launched to conceal that something has happened to
MUTSU. To further prevent rumors from spreading, many survivors are
later sent to remote garrisons on Tarawa, Makin, Kwajalein, Saipan and
Truk.
9 June 1943:
Hashirajima: At about 0200, MUTSU’s stern section sinks and comes to
rest nearly upright in 130 feet of water in Hiroshima Bay at 33-58N,
132-24E.
In the morning, the first divers arrive and remain on the site for
several months. FUSO serves as the "headquarters" for the salvage
efforts. To conceal that MUTSU has sunk the divers are told that the
ship they are exploring is similar to sister-ship NAGATO. Then the
divers are allowed to familiarize themselves on NAGATO.
The final list of those lost aboard MUTSU totals 1,121 men
including her skipper, Captain Miyoshi and his Executive Officer,
Captain Ono Koro (former CO of Japanese Battleship KIRISHIMA Kongo Class), both of whom are promoted to
Rear Admiral, posthumously.
Tokyo: The IJN suspects that the Type 3"Sanshiki-dan" incendiaries are
the cause because a fire at the Sagami arsenal a few years earlier was
caused by improper storage of the incendiary materials. After the
accident, the Minister of the Navy, Admiral Shimada Shigetaro (former
CO of Japanese Battleship HIEI Kongo Class) orders the Type 3 shells offloaded from all IJN ships
carrying them.
Hashirajima: The "M-Commission" led by 60-year old Admiral Shiozawa
Koichi (former CO of Japanese Heavy Cruiser FURATAKA class unknown) is convened to conduct a formal accident
investigation. Shiozawa considers all possibilities from the possibile
detonation of "Sanshiki" shells to improbable attacks by a lone
American torpedo plane or an attack by either a midget or fleet
submarine.
Cdr Yasui Yasukado, the inventor of the "Sanshiki" shells is called in
to testify. Tests are conducted at Kamegakubi on some shells salvaged
from turret No. 3 and on shells from the previous lot and the next lot.
An experiment is conducted by engineer troops with dozens of witnesses
of the accident who had survived. The test uses a specially built model
of turret No. 3. The final experiment is also based on the
identification of the color of the smoke generated during the burning
of Sanshiki shells compared to gunpowder. The smoke of burning powder
is reddish-brown, while the smoke of burning Sanshiki shells is white.
The witnesses of the disaster insist that they saw reddish-brown smoke.
Moreover, during testing, it becomes clear that explosions do not occur
below 80 degrees Centigrade. Cdr Yasui only escapes blame for the
disaster by the IJN's top brass because the tests disclose that the
Type 3 shells do not explode easily.
The M-Commission labors for two months and prepares their report.
The commission doubts that the shells had caused the disaster. As a
result the loading of Sanshiki shells on board ships is resumed. Later,
the IJN revises completely their standards for the handling and storage
of explosives aboard ships.
The investigation concludes that the explosion was "most likely
caused by human interference". Some investigators think there was a
ring of saboteurs, but the principal suspect is a disgruntled seaman
gunner of turret No. 3 who had brooded over theft charges and was
killed in the blast. The divers search for his body but it is never
found. During the war, the belief persists that, somehow, he managed to
escape.
22 July 1943:
Although the divers report that MUTSU is "bent like a broken nail", it
is proposed to salvage the ship, tow it to a drydock at Kure and put
her back on the line - optimistically - in three months. To convince
their superiors in Kure, a dive is made with a modified 6-man minisub,
but it snags on a railing on MUTSU. All officers aboard almost
suffocate before the minisub breaks free. Finally, it is decided that
it is impossible to raise MUTSU.
15 August 1943:
The survivors of MUTSU stationed on FUSO are transferred to NAGATO
that, with other fleet units, departs via Yashima and Yokosuka for
Truk. Once the survivors arrive on Truk, they form the reserve unit of
the local 41st Guard Force. About 150 are sent to Saipan and almost all
are killed there in 1944 during the U. S. invasion of the Marianas.
1 September 1943:
Removed from the Navy List.
Doubts as to the cause of the disaster remain, especially by those who
favor the explanation that a submarine attacked MUTSU. Several months
later IJN officials question the German naval attaché in Tokyo, Vice
Admiral (later Admiral/Knight's Cross) Paul Wenneker (former CO of
Panzerschiff also known as German Pocket Battleships DEUTSCHLAND/LUTZOW), about the circumstances surrounding
British Operation "Source." Only after completing the exploration of
MUTSU's wreck, do the Japanese decide that, indeed, the explosion must
have occurred from within the magazine itself. [2]
July 1944:
The oiled-starved IJN cut a hole in the bottom of MUTSU’s hulk and pump
out 580-tons of fuel oil for use by their ships in Operation Take
("Bamboo").
31 July 1945:
Seletar Naval Base, Singapore. Heavy Cruiser TAKAO (Mogami Class) is attacked and damaged
heavily by British X-craft. For some, doubts return about the cause of
the loss of MUTSU.
1949:
The first salvage attempt is made but soon abandoned.
20 March 1970:
The Fukada Salvage Company acquires the salvage rights to the
wreck. Salvage operations start soon thereafter and continue for eight
years.
23 August 1970:
Turret No. 4 is salvaged. Since then many artifacts are brought up
including gun barrels, propellers, the bow section, anchors and
crewmembers' personal belongings. The No. 4 turret is displayed at
Etajima.
February 1972:
The bow section is lifted in a two-stage operation in using a
1,500-ton floating crane. 272 crewmembers remain entombed within the
ship.
November 1972:
The MUTSU Memorial Museum opens in Tôwa Chô.
1978:
Salvage operations cease.
27 April 1994:
The museum moves into a new building.
1995:
According to a statement by the MUTSU Memorial Museum, no further salvage operations are planned.
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