Admiral Isoroku Yamamoto
Imperial Japanese Navy (IJN) Commander Combined Fleet

Background
Isoroku Yamamoto 山本 五十六 was born April 4, 1884 in Nagaoka in Niigata Prefecture on Honshū in Japan. On August 20, 1928 appointed as the Commanding Officer (C.O.) of Light Cruiser Isuzu. On December 10, 1928 appointed as the Commanding Officer (C.O.) of Akagi until November 1, 1929.

Pacific War
During World War II, Admiral Yamamoto was Commander in Chief (CinC) of the Imperial Japanese Navy (IJN) Combined Fleet.


On May 17, 1942 at Kure inspects damaged Shōkaku with Vice Admiral Ugaki.

On February 11, 1943 Yamamoto designates Battleship Musashi as his flagship at Truk.

Operation I-Go
On April 3, 1943 Yamamoto embarked aboard H8K2 Emily at Truk and was flown to Rabaul. The purpose of his visit was to personally oversee Operation I-Go (Sakusen A) using Japanese Navy land based bombers and fighters to attack Allied targets in the Solomon Islands and New Guinea. During I-Go, Admiral Yamamoto was photographed at Lakunai Airfield with this staff and waving or saluting to air crews wearing a Type 1 summer uniform His presence greatly contributed to moral and fighting spirit.


On April 7, 1943 the first phase X Attack began with an air strike against Allied ships in Tulagi Harbor. On April 11, 1943 the second phase targeted Allied ships in Oro Bay. On April 12, 1943 the third phase targeted Port Moresby. On April 14, 1943 two strikes were conducted against shipping and airfields at Milne Bay. On April 16, 1943 the last phase of the operation was canceled due to bad weather.

In total, Japanese land based bombers flew eighty sorties, loosing eight Bettys plus five seriously damaged. The carrier bombers operating land based conducted a total of 115 sorties with seventeen lost. A total of 487 fighter sorties were flown with 17 lost and two seriously damage. The Japanese pilots believed they had inflicted tremendous damage on the Allies ships and claimed 134 Allied aircraft shot down with 39 uncertain claims.

At the conclusion of the Operation I-Go, Yamamoto and his senior staff planned an inspection tour of forward airfields and bases in the Shortlands and southern Bougainville area. The purpose of this visit was to boost moral after the Japanese losses on Guadalcanal and thank the Japanese Army for cooperation.

April 18, 1943 "Yamamoto Mission"
On April 18, 1943 at dawn, two G4M1 Betty bombers from Vunakanau Airfield landed at Lakunai Airfield near Rabaul to pickup Yamamoto and his senior staff for the inspection tour. Aboard the first bomber, G4M1 Betty 2656 Tail 323 four passengers boarded this aircraft including: Admiral Isoroku Yamamoto, Rear Admiral Rokurou Takata, Cdr Kurio Toibana and Noburu Fukusaki plus their baggage.

Aboard the second bomber, G4M1 Betty Tail 326 five passengers boarded Vice-Admiral Matome Ugaki, Captain Motoharu Kitamura, Rinji Tomoro, Kaoru Imananka and Suteji Muroi. At 6:10am both Bettys took off from Lakunai Airfield and flew southeast bound for Ballale Airfield. Over southern Bougainville, intercepted by P-38 Lightings from 399th Fighter Squadron and shot down.

Recovery of Remains
After the crash, an Imperial Japanese Army patrol under the command of Lt. Mitsuyoshi (Tsuyoshi) Hamasuna from the 17th Army at Aku observed smoke rising from the jungle.  At first, they believed an American aircraft had crashed. Immediately, Lt. Hamasuna selected ten men from his platoon to search but was unable to find the plane and was told to try again the next day. Meanwhile, an Imperial Japanese Navy (IJN) patrol from the Sasebo 6th SNLF was also sent to the crash site to recover the remains of Yamamoto and the crew.

On April 19, 1943 Lt. Mitsuyoshi (Tsuyoshi) Hamasuna led a group of twelve back into the jungle and near dusk reached the crash site. That night, they departed and ran into the search group from the Sasebo 6th SNLF.

On April 20, 1943 both search parties: Hamasuna and the 6th SNLF returned to the crash site and recovered the remains of Yamamoto and the crew, transporting them southward to the mouth of the Wamai River on the southern coast of Bougainville. Afterwards, Hamasuna's group returned to Aku and Cdr Watanabe and his party arrived.

Many English published accounts and references claim Yamamoto died in his seat, from a bullet wound to his chest. This is an imagined myth and is not supported by firsthand Japanese accounts. The Japanese eyewitnesses to Yamamoto's body reported few visible wounds and resulted in speculation he might have survived the initial crash and died hours later from internal injuries. The later autopsy proved he was hit in the back and face and likely dead before the crash.

On April 20, 1943 his remains were placed aboard Minesweeper W-15 (many sources incorrectly state it was a subchaser) and an initial inspection of his body was conducted aboard (some sources describe as an autopsy). The recovered remains were transported to Buin (Kangua) then to the 1st Base Command at Buin.

On April 20, 1943 a full autopsy on Yamamoto's body was preformed by LtCdr Tabuchi Jisaburo, Chief Medical Officer, 1st Base Force.

On April 21, 1943 Yamamoto's body was dressed in his uniform and placed into a cremation pit, doused with petrol and cremated by Commander Watanabe. The remains of the rest of crew and passengers were cremated in two nearby pits. After his cremation, some of Yamamoto's remains were buried in an unmarked grave at Buin.

On April 22, 1943 the remainder of Yamamoto's remains were transported to Buin Airfield (Kahili) and loaded aboard another G4M1 Betty and flown back to Lakunai Airfield and were placed overnight the Third Fleet headquarters. On April 23, 1943 the ashes were loaded aboard two G4M1 Betty bombers and departed Lakunai Airfield bound for Eten Airfield (Takeshima) at 1:45pm. His remains were secretly transferred to the Admiral's sea cabin aboard Battleship Musashi at Truk and departed for Japan arriving on May 3, 1943.

In Japan, news of Yamamoto's death was officially reported to the press as "having died in combat aboard an aircraft". On June 5, 1943 Yamamoto received a state funeral in Tokyo. His ashes laid in state at the Navy Club in Tokyo then is transported on a gun carriage to Hibiya Park before being permanently buried at Tama Cemetery. A portion of his ashes was given to his wife and buried at his family shrine in Nagaoka.


Memorials
During the war, at the G4M1 Betty 2656 Tail 323 crash site the Japanese built a shrine at the crash site. At the Yamamoto cremation site at Buin, two papayas were planted and a stone with his name caved into it atop.

In the 1960s, a Japanese delegation visited the crash site and placed a memorial plaque on the admiral's seat that read "Last place of Admiral Yamamoto". In the early 1970s, when the commander's seat was removed, the plaque was left at the crash site. The plaque was last documented in 2002 and was missing since 2004. Since the war, Japanese visitors often leave small wooden sticks with prayers or messages at the crash site.

In 1999, the Isoroku Yamamoto Memorial Hall & Museum opened in Yamamoto's hometown of Nagaoka. The museum displays the left outer wing of his Betty bomber and aircraft commander's seat where the Admiral was seat when he died. Both are on permanent loan from the PNG Museum.


References
Kodochosho, 705 Kōkūtai, April 18, 1943
13th Fighter Command "Fighter Interception Report" April 18, 1943
USAF Historical Study No. 85 USAF Credits For The Destruction of Enemy Aircraft, World War II [PDF] Barber Rex T. page 17 (PDF page 22), Lanphier Thomas G Jr. page 111 (PDF page 118), 70 FTR SQ page 365 (PDF page 569), 339 FTR SQ 608 (PDF page 612)
Nippon Times “Fighting Spirit Surges Up Among Men of Nippon Navy” by Hiroshi Okamoto (Navy Press Corps) May 27, 1943, page 2 (left)
Nippon Times “Inspired Our Navy Wild Eagles” (Photo) May 27, 1943, page 2 (center)
Nippon Times “Yamamoto’s ashes to be buried here - granted site in Tama Cemetery next to grave of Fleet Admiral Togo” May 27, 1943, page 2 (right)
Nippon Times “Fleet-Admiral now rests in Tama Cemetery; entire nation pays homage at state funeral” June 6, 1943, page 1 (headline)
Nippon Times “Thousands attend services held in Hibiya Park compound as East Asia joins in tribute” June 6, 1943, page 1 (right)
Nippon Times “Final Ceremonies for Fleet-Admiral set at Tama Today” June 6, 1943, page 1 (center right)
Nippon Times “Farm in New Guinea jungle is dedicated to memory o Fleet-Admiral Yamamoto” by Hiroshi Mashita (Navy Press Corps) January 26, 1944 page 2 (center upper)
Nippon Times “Farm in New Guinea jungle is dedicated to memory o Fleet-Admiral Yamamoto” by Hiroshi Mashita (Navy Press Corps) January 26, 1944 page 2 (center upper)
Nippon Times “Yamamoto Foresaw Defeat for Japan in 1943” November 14, 1945 page 1 (center lower)
Admiral Jinichi Kusaka (1958) part 5 Fleet Admiral Yamamoto
Nippon Times “12:45-1:00pm (ch. 6) ‘Women’s News’ December 26, 1966 page 5 (right lower)
“Adm Isoroku Yamamoto of Japan’s once vaunted navy crashed in his plane as he headed on an observation trip from Rabaul to Bougainville [sic Ballale], due to an attack by U.S. P38 fighter plane over Bougainville. His body was recovered and a national funeral was held; but the wreckage of the plane in which he crashed was left at the site. Hiroyuki Akawa, who wrote the novel ‘Yamamoto Isoroku,’ visited Bougainville in November and managed to find a fragment of what seems to be the plane in question. The designer of the plane Suero Honjo of the SDF University on inspecting the piece of wreckage, averred it to be unmistakably that of Isoroku Yamamoto’s plane, and plans are about to retrieve the entire plane.”
Japanese Information Clearinghouse Bulletin (1983) Issue 1 18 April The Admiral's Last Flight 1943–1983
Yamamoto Autopsy (1971) by Chikamasa Ninagawa
Rust In Peace (1975) page 201-207
The Reluctant Admiral (1979) pages 374-378
Pacific Aircraft Wrecks... And Where To Find Them (1979) pages 34 (photos)
Air Force Board for Correction of Military Records testimony of Dr. Charles Darby, October 17-18, 1991 (AFBMR Docket: 91-02347) "There was no evidence on any remaining wreckage of an attack from the bomber's starboard beam as related in all of Lanphier's accounts."
Papua New Guinea Pacific War Images (1984)
Attack on Yamamoto (1990) page 102 (photos) 230-231
Fading Victory The Diary of Admiral Matome Ugaki 1941-1945 (1991) pages 222-223, 330-331, 350-360 plus footnotes
Pacific Air Combat WWII (1993) "A country boy from Niigata Prefecture" pages 32-35
Ballale Naval Engineering Group (1994) part 7, section 4 The Fleet Admiral shot down
Hostages To Freedom The Fall of Rabaul (1995) page 177, 179, 184
P-38 Lightning Aces of the Pacific and CBI (1997) chapter 2 "The Yamamoto Mission" pages 14-17
Last Flight Of Yamamoto (1999) by Jack Fellows
Yamamoto Crash Site Landowner Association (1999, 2002)
Osprey Combat Aircraft 22 Mitsubishi Type 1 Rikko 'Betty' Units of WWII (2001) by Osamu Tagaya page 52 (profile 12), 70-71, 107, 112 (index)
13th Fighter Command in World War II (2004) chapter 8 Yamamoto Mission by Jim Lansdale pages 137 -162, 320 (profile)
USNI Blog "The Solomons Campaign: Operation Vengeance – The Shootdown Of Yamamoto" (2009)
Fortress Rabaul (2010) pages 342-343
Aviation History Magazine "Death by P-38" (2012) by Don Hollway
Killing a Peacock: A Case Study of the Targeted Killing of Admiral Isoroku Yamamoto (2015) by Maj Adonis C. Arvanitakis
ABC "Japanese ambassador to PNG HE Hiroharu Iwasaki with Deputy Director of National Planning at the Yamamoto crash site" (May 12, 2015) by Sam Bolitho
Military History Magazine "Yamamoto Crash Site Reopens to Visitors" November 2015 page 12
Chicago Tribune "Does Chicago hot dog king have WWII Japanese admiral's gold tooth?" by Ted Gregory September 18, 2016
Japan Times "Chicago hot dog czar may have Japanese World War II admirals’s gold tooth" September 21, 2016
World War II Magazine "Appraising An Unexpected discovery" Jan/Feb 2017 Vol. 31 Issue 5, p12
The Japan Times “Museum honoring Adm. Yamamoto opens” April 17, 1999 page 3 (lower left)
Mitsubishi Type 1 Rikko 'Betty' Units of WWII (2001) page 70-71
Solomons: April to mid-June (2018) by Richard Dunn
Operation A: New Guinea (2018) by Richard Dunn