Marine Corps Air Station Iwakuni
Iwakuni, Yamaguchi Prefecture in Japan
A US Marine Corps KC-130J Super Hercules of VMGR-152 taxies to the runway at MCAS Iwakuni in 2014.
MCAS Iwakuni is located in Yamaguchi Prefecture
MCAS Iwakuni
MCAS Iwakuni
Location in Japan
MCAS Iwakuni is located in Japan
MCAS Iwakuni
MCAS Iwakuni
MCAS Iwakuni (Japan)
Coordinates34°08′42″N 132°14′39″E / 34.14500°N 132.24417°E / 34.14500; 132.24417
TypeMarine Corps Air Station
Site information
OwnerVarious (leased by Government of Japan and made available to the US)
Controlled byMarine Corps Installations Pacific (MCIPAC)
ConditionOperational Edit this at Wikidata
Site history
Built1940 (1940)
In use1940 – present
Garrison information
Colonel Richard M. Rusnok, Jr.
Airfield information
IdentifiersIATA: IWK, ICAO: RJOI, WMO: 477640
Elevation3 metres (10 ft) AMSL
Direction Length and surface
02/20 2,440 metres (8,005 ft) Concrete
Other airfield facilities1x seaplane ramp and 1x V/STOL pad
Airfield shared with Iwakuni Kintaikyo Airport.
Source: Japanese AIP at AIS Japan[1]

Marine Corps Air Station Iwakuni or MCAS Iwakuni (岩国飛行場, Iwakuni hikōjō) (IATA: IWK, ICAO: RJOI) is a United States Marine Corps air station located in the Nishiki river delta, 1.3 NM (2.4 km; 1.5 mi) southeast of Iwakuni Station[1] in the city of Iwakuni, Yamaguchi Prefecture, Japan.


The Japanese government bought a large portion of what is today MCAS Iwakuni in 1938, with the view of establishing a naval air station. They commissioned the new base on 8 July 1940. When World War II started, the Iwakuni Air Station was used as a training and defense base. The station housed 96 trainers and 150 Zero fighter planes on the airstrip. In September 1943, a branch of the Etajima Naval Academy was established here, with approximately 1,000 cadets undergoing training in the Basic, Junior, and Senior Officer's schools at any one time. American B-29's bombed Iwakuni in May and August 1945, concentrating on the oil refinery and Rail Transport Office or train station areas. The last air raid took place just a day before the war was brought to a close.

The first allies to reach Iwakuni at the war's end were a group of U.S. Marines who had signed papers ending the conflict for the Japanese air base. After the end of World War II, various military forces from the United States, Britain, Australia, and New Zealand occupied the base and it was repaired by No. 5 Airfield Construction Squadron RAAF and designated a Royal Australian Air Force Base in 1948. The Americans first occupied the base in 1950 to use it as a springboard for aircraft heading to the Korean War. In 1952, the base officially became a United States military base.[2]

F-51Ds of RAAF No. 77 Squadron in maintenance at Iwakuni Airfield, June 1950.

Iwakuni had scheduled international service by private airlines from 1952 to 1964, during which time it had the IATA airport code IWJ. This code was later reassigned to Iwami Airport in neighboring Shimane Prefecture.[3]

Nuclear weapons were moved from Okinawa to the base for storage during a brief period in 1966. When U.S. ambassador to Japan Edwin O. Reischauer learned of the presence of the weapons, which was a violation of the Treaty of Mutual Cooperation and Security between the United States and Japan, he told the United States Department of State that if the weapons were not removed within 90 days he would resign and go public with the information. The weapons were removed shortly thereafter, and their presence at the base did not become publicly known until 2010.[4]

It is currently home to around 10,000 United States Marines, sailors, and family members. The base is detailed for Marine pilot training and air patrol, using F/A-18 Hornet fighter-attack aircraft among others in compliance with the Treaty of Mutual Cooperation and Security obligations to protect Japan. MCAS Iwakuni is also shared with the Japanese Maritime Self Defense Force. MCAS Iwakuni is home to a Department of Defense school, Matthew C. Perry (Elementary, Middle School, and High School).

USMC F/A-18D takes off from MCAS Iwakuni in December 2005

A new off-shore runway opened at the base on 30 May 2010. The new runway is 2,440 meters in length.[5]

On 22 November 2017, a C-2A Greyhound cargo plane with 11 crew and passengers aboard crashed southeast of Okinawa after departing the base for the aircraft carrier USS Ronald Reagan. Eight of the 11 were rescued.[6]

On 6 December 2018, a F/A-18D Hornet (callsign "Profane 12") belonging to VMFA(AW)-242 collided mid-air with a KC-130 (callsign "Sumo 41") from VMGR-152 during a nighttime training exercise. The crew of Sumo 41 were killed in the collision along with the pilot of Profane 12. The co-pilot of Profane 12 was rescued by JMSDF Search & Rescue in Japanese waters. An investigation into the accident was led by the Marine Corps. ProPublica later conducted their independent investigation after finding the Marine Corps's initial results to be inaccurate.[7][8]

USN Carrier Air Wing 5 relocation to MCAS Iwakuni

Since at least 2005 there had been plans to relocate Carrier Air Wing Five's fixed wing aircraft from Naval Air Facility Atsugi in Kanagawa Prefecture to Iwakuni.[9] Yamaguchi governor Sekinari Nii said there was "no way" Yamaguchi prefecture would accept this.[10] In 2006 Iwakuni voters rejected the plan in a plebiscite[11] and Iwakuni mayor Katsusuke Ihara urged Tokyo to drop the plan.[12] In 2007 the Japanese government passed legislation to prepare for the relocation of US Forces in Japan including subsidies for local affected areas.[13]

The move was planned to have been done in 2014, but after construction delays the move was delayed by three years, to 2017.[14][15][16]

The move did not include the wing's two helicopter squadrons. The first CVW-5 squadron, VAW-125 flying the E-2D Hawkeye arrived in January 2017. The Boeing E/A-18G Growlers of VAQ-141 "Shadowhawks" completed relocation in January, 2018. By March 2018, all fixed wing aircraft of Carrier Air Wing 5 had completed relocation from NAF Atsugi.[17]

USMC F-35B aircraft

The first aircraft of Marine Fighter Attack Squadron 121 "Green Knights" (VMFA-121) arrived on 18 January 2017.[18] This became the first forward deployed F-35B Lightning II squadron in the United States Marine Corps. They have since flown show of force sorties against North Korea.[19]

Role and operations

F-35B Lightning IIs with Marine Fighter Attack Squadron (VMFA) 121, taxi to the runway at Marine Corps Air Station Iwakuni

US Marine Corps

Taxiing F/A-18D Hornet of VMFA(AW)-242 at Marine Corps Air Station Iwakuni (2018)

Marine Aircraft Group 12 (MAG-12) contains the rotary and fixed wing aircraft assets of Marine Corps Air Station Iwakuni. MAG-12 is home to three flying squadrons, an aviation logistics squadron, and a ground support squadron.

US Air Force

The 374th Communications Squadron provides communications support to H&HS, MAG-12, Branch Medical Clinic Iwakuni, Army Corps of Engineers, and the JMSDF.

Based units

Flying and notable non-flying units based at MCAS Iwakuni.[21][22][23]

Commercial services

Iwakuni Kintaikyo Airport

Regular commercial service started from 13 December 2012 with a civilian airport terminal built to accommodate commercial flights. It was initially projected that up to 430,000 passengers would use the airport each year,[24] and in the first seven months of operations the airport handled over 200,000 passengers, with average load factors between Iwakuni and Tokyo exceeding 70% during June 2013.[25]

Since the IATA airport code IWJ, formerly assigned to Iwakuni, was reassigned to Iwami Airport, a new IATA code of IWK was assigned to Iwakuni. The inaugural flight was operated by All Nippon Airways from Haneda Airport. Iwakuni Airport is called by its official nickname "Iwakuni Kintaikyo Airport", named after the Kintaikyo bridge near the airport. In the future, the airport plans to serve international flights to China and South Korea, as well as more cities within Japan.

Airlines and destinations

All Nippon Airways Tokyo–Haneda
ANA Wings Naha,[26] Tokyo–Haneda

Friendship Day

A child tries on a Kevlar helmet during the Marine Corps Air Station Iwakuni Friendship Day 2016 Air Show, 5 May 2016.

Every year on 5 May, Japanese nationals and U.S. service members, government employees and their families officially celebrate their long-standing friendship by opening the gates of MCAS Iwakuni for one of Japan's largest air shows dedicated to enhancing the friendship of the two nations. The event, entitled Friendship Day, hosts an average 250,000 visitors who travel from all over Japan.[27][28]

See also


This article incorporates text in the public domain from the United States Marine Corps.

Public Domain This article incorporates public domain material from the Air Force Historical Research Agency

  1. ^ a b AIS Japan
  2. ^ MCAS Iwakuni, Japan. (n.d.). MCAS Iwakuni History. Retrieved 17 March 2010, "History". Archived from the original on 13 March 2016. Retrieved 5 January 2016.
  3. ^ "12月開港の岩国空港略称、「IWK」に決まる". Nihon Keizai Shimbun. 28 July 2012. Retrieved 11 March 2014. 国交省大阪航空局などによると、1952~64年の間、岩国は国際空港として民間機が発着しており、このときの略称はIWJだったという。これは現在、石見空港(島根県益田市)の略称として使われている。
  4. ^ Jiji Press/Kyodo News, "U.S. kept nuclear arms at Iwakuni in 1966: scholar", Japan Times, 17 March 2010, p. 1.
  5. ^ Japan Times, "New Offshore Runway at U.S. Iwakuni Operational", 30 May 2010.
  6. ^ Rich, Motoko (22 November 2017). "Navy Aircraft With 11 Aboard Crashes into Waters Off Japan". The New York Times. Retrieved 22 November 2017.
  7. ^ Miller, Robert Faturechi,Megan Rose,T Christian. "Faulty Equipment, Lapsed Training, Repeated Warnings: How a Preventable Disaster Killed Six Marines". ProPublica. Retrieved 15 May 2021.((cite web)): CS1 maint: multiple names: authors list (link)
  8. ^ Miller, Robert Faturechi,Megan Rose,T Christian. "U.S. Marine Corps Concludes Its Investigation Into a Fatal 2018 Midair Crash Was Inaccurate". ProPublica. Retrieved 15 May 2021.((cite web)): CS1 maint: multiple names: authors list (link)
  9. ^ Iwakuni to take in Atsugi jets? 4 Jun 2005 Japan Times Retrieved 10 August 2016
  10. ^ Yamaguchi governor rips Iwakuni move 31 October 2005 Japan Times Retrieved 10 August 2016
  11. ^ Johnston, Eric Iwakuni voters reject realignment plan 13 Mar 2006 Japan Times
  12. ^ Drop base plan: Iwakuni mayor 17 March 2006 Japan Times Retrieved 10 August 2016
  13. ^ Diet enacts law that paves way for U.S. forces realignment 24 May 2007 Japan Times Retrieved 10 August 2016
  14. ^ Air wing's move from Atsugi to Iwakuni delayed 3 years 25 January 2013 Stars and Stripes Retrieved 10 August 2016
  15. ^ Reducing military jet noise 9 August 2015 Japan Times Retrieved 10 August 2016
  16. ^ Suga visits Yamaguchi for consent to transfer U.S. carrier wing to base in Iwakuni 5 February 2017 Japan Times Retrieved 5 February 2017
  17. ^ Final Japan-Based CVW-5 Jet Squadrons Fly-in to MCAS Iwakuni (press release), Commander Navy Region Japan Public Affairs Office, 28 March 2018
  18. ^ Insinna, Valerie (10 January 2017). "First F-35B Squadron Moves to Japan". Retrieved 8 March 2018.
  19. ^ LaGrone, Sam (31 August 2017). "Marine F-35s, Air Force Bombers Sortie with South Korea, Japan in Show of Force After North Korea Missile Tests". USNI News. Retrieved 9 March 2018.
  20. ^ Headquarters and Headquarters Squadron
  21. ^ Kaminski, Tom (2019). "Aircraft of the US Navy and US Marine Corps". US Navy & Marine Corps Air Power Yearbook 2019. Key Publishing. pp. 68–92.
  22. ^ "Organizations". MCAS Iwakuni. US Marine Corps. Retrieved 27 June 2020.
  23. ^ Air Station Iwakuni - Unit (Japanese) Archived 22 January 2013 at the Wayback Machine
  24. ^ Tritten, Travis J.; Sumida, Chiyomi (19 February 2010). "Japan carrier to offer Iwakuni flights". Stars and Stripes. Retrieved 8 January 2019.
  25. ^ "開港半年の岩国空港、利用は堅調". 日本経済新聞. Retrieved 5 August 2013.
  26. ^ "ANA Adds New Domestic Routes in S16". airlineroute. Retrieved 10 February 2016.
  27. ^ "Press Conference for 2008 Friendship Day" (Press release). MCAS Iwakuni, United States Marine Corps. 8 April 2008. Archived from the original on 26 April 2008. Retrieved 10 June 2008.
  28. ^ "Friendship Day website" (in Japanese). Archived from the original on 1 May 2008.