Flying Boats at Iwakuni Air Station; Iwakuni, November 8, 2019

Japan Maritime Self Defense Force, part 7; Text and Photograph's by Alex van Noye

The maritime airbase Iwakuni Air Station is home to the Japanese 31st Fleet Air Wing which is part of the Japan Maritime Self Defense Force. This unit flies with several versions of the P-3 Orion, the EH101 Merlin and uses the US-2 flying boat. There are also US aircraft from the US Navy and the Marines based on Iwakuni.

The Japanese 31st Fleet Air Wing (Di Sanshi Hangkong Jituan) (31 FAW) is part of the Japan Maritime Self Defense Force (JMSDF). The unit falls under the Japanese Navy's aviation command and is based on Iwakuni Air Station. The unit is led by an assistant naval admiral. The 31 FAW is a specialized unit of the JMSDF aviation service. The 31 FAW is made up of three units that are equipped with different types of aircraft. The first unit is the 81st Fleet Air Squadron and is equipped with the EP-3C Orion and the OP-3C Orion. These versions of the Orion are used for electronic observations and intelligence. The aircraft of the 81st Fleet Air Squadron operate under the name "Violet" and therefore mainly act in the role of gathering information above the sea and creating images of the situation on and below sea level. The OP-3C is equipped with SLAR (Side Looking Areal Radar) or LOROP (Long Range Optics). The second unit at Iwakuni is the 91st Fleet Air Squadron and is equipped with the UP-3D Orion and the U-36A. These aircraft serve to support training for electronic warfare and anti-aircraft training by naval units. The UP-3D no longer has a MAD system in the tail of the aircraft and is used purely and exclusively for electronic warfare. The U-36A is suitable for training with ships in the field of electronic warfare and the aircraft is also capable of dragging targets for shooting practice. The aircraft of the 91st Fleet Air Squadron operate under the name "Delphi" and "Cupid".

The best known unit of the JMSDF units at Iwakuni is the 71st Fleet Air Squadron. This unit is equipped with the US-2 Shin Meiwa flying boat for SAR duties. US-2 is a flying boat developed by Shin Meiwa Industries and specializes in ocean rescues. The Japan Maritime Self-Defense Force has introduced the type as a successor to US-1A. The latter type dates back to the early 1970s and has been phased out by the Japanese navy since 2017. The US-2 is an amphibious aircraft that is comparable to the US-1, since it is a further developed variant of its predecessor. The US-1A was redesigned

as a rescue aircraft and turned out to be an excellent flying boat compared to the PS-1 which was derived from a patrol aircraft. The type was further developed, because the customer, the JMSDF, set higher requirements for such a type. The aircraft had to have better maneuverability when taking off and landing and the aircraft had to have better facilities for patient transport and improved offshore rescue capabilities. When it became known that the US-1 would be phased out after more than forty years of service, the development of its successor in this role was started in 1991. The development of the US-1 Kai was finally started by Shin Meiwa from October 1996. The builder Shin Meiwa entered into a partnership with aircraft builders such as Kawasaki Heavy Industries, Fuji Heavy Industries and Nippon Aircraft to build the flying boats. The design was later renamed as the "US-2 Rescue Flying Boat" and was officially deployed from March 2007, after the MoD had approved the aircraft.

The US-2 is a strong technical advance compared to the US-1. Unlike the US-1, the US-2 has a fly-by-wire system and the aircraft also has an autopilot on board. The US-2 has a fully glass cockpit and a pressure cabin, which gives passengers and patients in the aircraft a much more pleasant flight. The US-2 also has improved engines and propellers, which has considerably reduced fuel consumption. Much lighter materials have also been used, such as composite materials in the design of the US-2, making the aircraft much lighter and better to fly. Finally, the US-2 also has a FLIR system which makes it easier to search above the sea. The 71st Fleet Air Squadron on Iwakuni is the only unit in Japan that operates with these flying boats. The JMSDF has received a total of only six of these flying boats for the SAR duties at sea. In addition to Iwakuni, there is also often a detachment of the 71st Fleet Air Squadron at Atsugi Air Station based near Tokyo. So far, the flying boats have been used several times to transport patients and to save people at sea. For example, on March 7, 2009, the unit provided assistance in the event of an accident at an asphalt plant in Minamitorishima. A US-2 was then deployed to transport the victims of that accident to a location where they could be treated. Also, a US-2 rescued humans at sea 1200 km off the coast of Japan after their ship was wrecked on June 13, 2013. The US-2 then carried out a landing rescue in the middle of the ocean to save the drowning people.

In addition to the 31st Fleet Air Wing, Iwakuni is also home to the 111th Fleet Air Squadron that operates as an independent component in the detection of sea mines. The unit is equipped with the MCH-101 Merlin for this task. The most important task of the unit is to detect and defuse sea mines on the Japanese shipping routes. There are still many remnants and old sea mines from the period of the Second World War around Japan that can cause danger. In addition to the JMSDF, the US Navy and USMC (Marines) also use Iwakuni as their home base. The majority of the maritime airbase is in use by the American units, because the Americans also house their personnel on the base. The American Marines Corps is the main user of Iwakuni. The units of the Marines on Iwakuni are VMFA(AW)-242 "Bats" which is equipped with the F/A-18D Hornet, VMFA-121 "Green Knights" which operates with the F-35B Lightning II and finally VMGR-152 "Sumos" which flies with the KC-130J Super Hercules. These combat units are the only Marines units that are permanently based at an air base outside the United States. In addition to the Marines, the Carrier Air Wing number 5 (CAW-5) is also based on Iwakuni. This whole unit is based at sea on board of the aircraft carrier "Ronald Reagan". The staff is normally based on Atsugi near Tokyo. However, due to noise there, the flying units have been moved to Iwakuni since 2017. The Ronald Reagan aircraft carrier is located in the harbor near Tokyo when the ship is not at sea. With these units, Iwakuni is one of the largest maritime airfields in Japan.