Tokyo-NP reported that Japan’s cabinet has finalized the defense budget for 2022 and Tokyo will allocate $445 million to buy four short take-off and vertical-landing (STOVL) F-35B fighters. Another $671 million will go towards the purchase of another eight conventional takeoffs and landing (CTOL) fighters. On 20 December 2011, the Japanese Government announced that it intended to purchase 42 F-35s for approximately US$8 billion, with the initial delivery to begin in 2016 to replace its existing F-4 Phantom II aircraft. To fully participate in the program, the Japanese government is loosening its weapons export ban.
In 2013, the Japanese government decided that since Japanese companies would merely function as subcontractors that these parts would be exempt from the usual weapons export ban. In August 2013, it was confirmed that Japanese companies will manufacture 24 components of the F-35 related to the engine and radar. Mitsubishi Electric will manufacture 7 components of the radar, and IHI Corporation will manufacture 17 fan and turbine components of the engine. Mitsubishi Heavy Industries will also be included in some form in the manufacturing of the rear fuselage, wings, and undercarriage, which will allow Japanese industry to gain a greater understanding of low-observability stealth technology and manufacture.
The United States has refused to share the F-35 software source code with its partners, despite their repeated requests for it. However, in April 2019, the United States proposed disclosing portions of that source code with Japan, if Lockheed Martin is successful in its bid to develop the new Japanese F-3 stealth fighter; those portions of the F-35 software would be reused for the F-3. On June 18, 2019, Japan’s Ministry of Defense requested the Pentagon to upgrade Japan’s status as a customer to a full-fledged partner of the F-35 program. This request comes around Turkey’s expulsion from the F-35 program. On 9 July 2020, the US Defense Security Cooperation Agency (DSCA) announced that the US Department of State has approved a potential US$23.11 billion sale of 105 F-35 aircraft to Japan – 63 F-35As and 42 F-35Bs, along with related equipment and services. This is in addition to the 42 F-35A already ordered. This would be the second-largest foreign military sale ever by the US. The deal still needs approval by the US Congress.
The Izumo-class multi-purpose destroyers or 22DDH are helicopter carriers in service with the Japan Maritime Self-Defense Force (JMSDF). The class is designated as a multi-purpose operation destroyer by the Japanese government due to limits on the Japanese Constitution prohibiting the acquisition of offensive platforms. In June 2020, Japan Marine United started work on refitting the first of two Japan Maritime Self-Defense Force Izumo-class helicopter destroyers for operations with the F-35B, confirming rumors of planned naval operation. To prepare JS Izumo for the operation of F-35Bs, a sum of $53 million was approved. Both ships of the class could operate STOVL Lockheed Martin F-35B Lightning II aircraft after modifications. Japan was planning to acquire 40 F-35Bs, the Short Take-off and Vertical Landing (STOVL) variant of the Lockheed Martin Lightning II Joint Strike Fighter (JSF), which could be operated from the Izumo class with some modifications to the ships. It was estimated that each Izumo-class carrier could operate 12 or more F-35B aircraft.