In early October two U.S. Marine Corps Lockheed Martin F-35B fighters performed the type’s first recoveries and launches from JS Izumo, one of two Japan Maritime Self-Defense Force (JMSDF) helicopter carriers to be modified to cater for F-35 operations in advance of the arrival of Japan’s own F-35Bs. In so doing, they became the first fixed-wing aircraft to operate from a Japanese vessel since the days of the Imperial Japanese Navy.
The F-35Bs came from VMFA-242 “Bats”, one of two Marine squadrons forward-based in Japan at Iwakuni. During the operation, they were refueled by a KC-130J from VMGR-152 “Sumos” from the same base. The aim of the operation was to demonstrate the ability of the type to operate from the vessel, which has recently completed the first phase of a modification to enable it to undertake F-35B operations.
“This trial has proved that the JS Izumo has the capability to support takeoffs and landings of STOVL aircraft at sea, which will allow us to provide an additional option for air defense in the Pacific Ocean in the near future,” said Rear Admiral Komuta Shukaku, commander of the JMSDF’s Escort Flotilla One. “We have work to do until the day the JMSDF can regularly employ STOVL aircraft at sea, but I am confident that the strong partnership and mutual trust between our two counties will result in its realization.”
Japan announced its intentions to acquire 42 of the short-takeoff/vertical landing (STOVL) version of the F-35B in August 2019, alongside a planned 100-aircraft buy of the F-35A land-based version. So far eight F-35Bs have been contracted. They are to be operated from two converted carriers, and from remote shore bases on Japan's islands.
In July 2021 the first modified ship, Izumo, returned to its homeport of Yokosuka following a routine five-yearly scheduled maintenance period with Japan Marine United in Yokohama. During its lay-up, a heat-resistant coating was applied to the flight deck to protect it from the effects of the F-35B’s downward-pointing exhaust, as well as new lighting and deck markings. The initial verification of the ability to recover and launch the F-35B was undertaken at the request of the Japanese defense ministry. Japan intends to operate the F-35B from its ships in a similar fashion to that employed by the Marines, with short rolling takeoffs and vertical recoveries. The two vessels will not be fitted with ski-jumps.
In the second phase of its modification, due in 2024, Izumo will have its bow re-shaped with a square end to the flight deck to facilitate F-35 operations. A second vessel, JS Kaga, is to enter the modification process around the end of the year, with the majority of the work—including the new bow shape—being accomplished in one phase. When the works are complete the ships will be able to embark a maximum of 12/14 F-35Bs.
In July it was announced that the principal shore base for the F-35B will be Nyutabaru, close to Japan’s southwest islands and also Kure, which is Kaga’s homeport. The aircraft will be operated by two Japan Air Self-Defence Force squadrons, each with around 20 aircraft. Japanese media reports that the first six aircraft are due in 2024, and another two in the following year. It is expected that initial operations from the two vessels will begin with U.S. Marine Corps aircraft in order to prepare JMSDF personnel for the beginning of operations by Japan's own F-35Bs.