The Defense Ministry is considering buying dozens of additional F-35 stealth fighter jets to replace Air Self-Defense Force (ASDF) F-15s, government sources said.
The ministry is already moving forward with the introduction of 42 F-35s to replace the ASDF's aging F-4 fighters.
U.S. President Donald Trump urged Japan to buy F-35s when he visited Japan in November. Tokyo's plan to buy more of the jets is partly aimed at fending off pressure from Washington to reduce the U.S. trade deficit with Japan.
The F-15 Eagle is a fourth-generation air superiority fighter. Japan began introducing the planes in fiscal 1980, and about 200 F-15s have been deployed. Around half of them are being upgraded to extend their service life, though the modernization program reportedly costs billions of yen per aircraft. The older planes in the F-15 fleet are set to be retired in the late 2020s, and the ministry has been considering new aircraft to replace them.
The F-35 Lightning II is a fifth-generation jet fighter with stealthy qualities, and is designed for both air combat and strikes on surface targets such as ships or enemy ground troops.
When President Trump visited Japan, he told a news conference that the F-35 is the world's best fighter plane and urged Tokyo to buy them, saying that a Japanese purchase would create many jobs in the U.S. and make Japan safer.
The Defense Ministry began to earmark funds in fiscal 2012 to purchase the first 42 F-35s, and will start deploying the new jet this fiscal year. Some 13 billion yen has been allocated for each aircraft in the fiscal 2018 budget, with budget appropriations to acquire the 42 fighters expected to wind down in fiscal 2020. The ministry is considering procuring additional F-35s to replace aging F-15s beginning in fiscal 2021. Introducing more of the same aircraft is expected to increase maintenance and pilot training efficiency.
The ASDF plans to introduce F-35As, a standard takeoff and landing model designed for air forces. However, a plan has emerged to buy some F-35Bs, a short takeoff and vertical landing variant in service with the U.S. Marine Corps. Under the plan, F-35Bs would be loaded on amphibious assault ships, which the Maritime Self-Defense Force plans to introduce to transport supplies and troops for the defense of Japan's far-flung island territories.