MELBOURNE, Australia — Japan and South Korea both reached milestones with their Lockheed Martin F-35 Lightning II Joint Strike Fighters.

The Japan Air Self-Defense Force or JASDF declared initial operating capability for its first F-35 squadron on March 29th when the 302 Hikotai at Misawa Air Base in the northern part of the main Japanese island of Honshu held a ceremony to celebrate its F-35As.

Vice Admiral Mat Winter, F-35 program executive officer said in a statement that “this is a major milestone for the F-35 enterprise, as it marks the first F-35 IOC for an Indo-Pacific region customer.”

The 302 Hikotai only stopped flying its last McDonnell-Douglas/Mitsubishi F-4EJ-kai Phantom IIs at its former base of Hyakuri, north of Japan’s capital Tokyo, the week prior. Another JASDF Phantom II squadron will transition to the F-35A over the next year.

Japan plans to eventually acquire a total of 157 F-35s, which will include 42 F-35Bs. It plans to use the latter variant, which is capable to short take off and vertical landing operations, to equip Japan’s Izumo-class helicopter destroyers. The ships, which are currently only capable of supporting helicopters on board, will be modified to handle F-35 operations.

Meanwhile, neighboring South Korea welcomed the first two F-35As on its soil that same day, when the aircraft were ferried across the Pacific to an air base in Cheongju, 140 kilometers southeast of the capital Seoul.

South Korea’s Yonhap News Agency quoted Wang Jung-hong, head of the Defense Acquisition Program Administration as saying that South Korea expects the F-35 “to enhance the Air Force’s operational capabilities in response to the neighboring countries’ introduction of stealth fighters, and to strengthen the readiness posture against threats from all directions."

The first South Korean F-35A was rolled out in March 2018 at Lockheed-Martin’s plant in Fort Worth, Texas and since that time the Republic of Korea Air Force or ROKAF has been training up its initial cadre of pilots and maintainers on its jets at Luke Air Force Base in Arizona. According to Yonhap, eight more F-35s are due to return to the country by the end of this year.

The U.S. ally has 40 F-35As on order under a 2014 contract worth about $7 billion, all of which will be delivered by 2021. Defense News understands that the first unit to operate the South Korean F-35s will be the ROKAF’s Cheongju-based 17th Fighter Wing.