The aircraft is the first of 42 F-35B Lightning IIs that will be delivered to the Japan Air Self Defense Force.
The Japanese F-35B BX-1 successfully completed its first test flight from Lockheed Martin Facility at NAS Joint Reserve Base Fort Worth, Texas, on May 12, 2025. Our friends and contributors Gherardo and Victoria Fontana caught the aircraft during the maiden flight, which started at 16:08 local time and lasted about an hour.
As usual with the first flight of a newly produced aircraft, the F-35B was escorted by an ATAC Mirage F-1 acting as safety chase. Notably, the aircraft has not received yet its full markings, with only the number 201 number stenciled below the canopy and the flaperons, as well as the Japanese roundel on the wing.
It appears that this first flight was not preceded by a formal rollout ceremony, or at least it wasn’t publicized. Also, the milestone follows the news back in January 2025 that the delivery of the first six F-35Bs to the JASDF (Japan Air Self Defense Force), which was planned to happen sometime during FY (Fiscal Year) 2024, has now been postponed to sometime during FY2025.
Japan plans to station the first batch of F-35Bs at Nyutabaru Air Base, which is located in the southern part of the island of Kyushu, due to the its close proximity to the home port of the JS Kaga in JMSDF (Japan Maritime Self Defense Force) Kure, in Hiroshima prefecture. The establishment of a temporary squadron for the F-35B in preparation for the induction continues as planned at Nyutabaru, and was expected to take place by the end of FY2024 (on Mar. 31, 2025).
With this first aircraft, Japan now joins the small pool of F-35B operators, which currently include the U.S. Marine Corps, the Italian Air Force and Navy and the UK’s Royal Air Force and Royal Navy. Singapore’s RSAF (Republic of Singapore Air Force) is also set to receive the B model in the future.
Japan’s F-35B acquisition
While initially it only acquired F-35As, Japan decided in 2018 to procure 42 F-35Bs in order to strengthen its capabilities and operate from its two aircraft carriers, small airstrips and remote islands. These 42 aircraft are part of the larger total of 147 F-35s that Japan plans to operate.
The plan was formally approved in Japan’s 2019–2023 Mid-Term Defense Program, which mentioned that 18 of the then-planned 47 F-35s would have been STOVL (Short Take-Off Vertical Landing) variants. The program of record for the F-35B was later increased to 42 aircraft.
The procurement was approved by the United States in 2020, and included both 63 F-35As and the 42 F-35Bs, for a total of 105 aircraft. According to the Defense Security Cooperation Agency’s notification to Congress, the sale was reported worth about $23.11 billion.
With 147 aircraft in service, Japan would become the second-largest operator of the F-35 after the United States. Japan also hosts in Nagoya one of three final assembly and check-out (FACO) facilities for the F-35 Lightning II program.
However, Japan’s F-35Bs will be produced in the U.S. at Lockheed Martin’s production facility in Fort Worth, Texas. The FACO facility continues to perform the final assembly and check-out of F-35A aircraft to be delivered to the JASDF, as well as Maintenance, Repair, Overhaul and Upgrade (MRO&U) activities for the North Asia region.
最終組立段階に入った🇯🇵空自向けF-35B初号機BX-1の最新写真
📷 Date Taken 2025-01-21 pic.twitter.com/ki67FbEjUT
— Fighterman_FFRC (@Fighterman_FFRC) February 21, 2025
The F-35B in Japanese service
Plans are in place to operate the STOVL fighter jets from the JMSDF’s two Izumo-class DDHs (Helicopter-carrying Destroyers), the JS Izumo and JS Kaga, which are currently undergoing conversion to allow F-35B operations. To better prepare for the arrival of the new aircraft, Japan is studying F-35s operations from other navies who already operate the type, such as the Italian Navy and Royal Navy.
The F-35B has undergone tests with Japanese vessels twice, with the Izumo conducting flight ops in 2021, while the Kaga just recently had a F-35B land on its deck. Both of these tests were conducted with non-Japanese jets and pilots. The Izumo is set to start F-35B operations in 2027, while the Kaga will induct it into service a year later in 2028.
Interestingly, although the aircraft are planned to operate from these JMSDF vessels, the F-35B itself will be operated by the JASDF. The service plans to operate up to 105 F-35A CTOL (Conventional Take Off and Landing) and 42 F-35B V/STOVL fighter jets alongside their previous inventory of F-15J/DJs and F-2A/Bs.
The JMSDF also operates its own fleet of fixed-wing assets, although it does not operate any fighter aircraft. Their fixed-wing fleet comprises mainly of maritime patrol aircraft such as various variants of the venerable P-3 and its successor, the domestically produced P-1, as well as transport aircraft like the C-130 and ShinMaywa US-2 floatplane.
