Four U.S. Marine Corps F-35B aircraft and a U.S. Navy CVM-22B Osprey conducted flight operations on the Japan Maritime Self-Defense Force’s largest destroyer, JS Kaga, in October. Naval News understands it was first time so many F-35B aircraft operated from JS Kaga. It was also the first time a Navy CVM-22B landed on a Japanese flat top.
This event took place as part of ANNUALEX, a Japan-U.S. bilateral exercise held from 20–31 October and conducted biennially under JMSDF leadership. This year’s ANNUALEX focused on strengthening the bilateral alliance within a multilateral context through maritime communications tactics, anti-submarine warfare (ASW) operations, air-defense warfare (AAW) operations, and underway replenishment.
On the Japanese side, approximately 20 ships—including Kaga—and roughly 20 aircraft participated. U.S. assets included the Arleigh Burke–class guided-missile destroyer USS Shoup (DDG 86), the Ticonderoga-class guided-missile cruiser USS Robert Smalls (CG 62), the P-8A Poseidon, the Lewis and Clark–class dry cargo/ammunition ships USNS Amelia Earhart (T-AKE 6) and USNS Wally Schirra (T-AKE 8), the fleet oiler USNS Tippecanoe (T-AO 199), U.S. submarines, and U.S. Marine Corps F-35B Lightning II aircraft. Beyond Japan and the United States, participating forces included the Royal Australian Navy and Royal Australian Air Force, the Royal Canadian Navy and Royal Canadian Air Force, the French Navy, and the Royal New Zealand Air Force.
The F-35Bs participating in the flight operations aboard JS Kaga belonged to Marine Fighter Attack Squadron (VMFA) 242, Marine Aircraft Group 12, 1st Marine Aircraft Wing, with additional deck-operations support provided by crew members from USS Tripoli. JS Kaga previously conducted its first F-35B flight trials with the U.S. Marine Corps in November 2024, followed by flight operations with F-35Bs from the UK Royal Navy’s aircraft carrier HMS Prince of Wales during its Indo-Pacific deployment in August 2025. The latest evolution therefore marks the third series of F-35B-related flight operations on JS Kaga.
Japan decided in 2018 to enable F-35B operations from JS Kaga in response to increased activity by Chinese bombers and other aircraft in the Pacific. The ship is undergoing a two-phase modification program. The first phase, conducted from March 2022 to March 2024, included reshaping the forward end of the flight deck from a trapezoid to a rectangle and adding heat-resistant coatings to withstand the F-35B’s exhaust. The second phase, scheduled from March 2027 to March 2029, will involve modifications to internal ship systems. Her sister ship, JS Izumo, is undergoing similar upgrades and is expected to complete all required modifications by March 2028.
