UK outlines role in fielding of F-35Bs on Japan's Izumo class

Commodore James Blackmore, commander of CSG25, is seen here on the flight deck of HMS Prince of Wales while it was in Singapore for its second stop in the country for 2025. (Janes/Ridzwan Rahmat)

Commander of the UK Royal Navy's Carrier Strike Group 25 (CSG25) Commodore James Blackmore has shed more light on the role that the service plays in Japan's ongoing effort to deploy F-35B Lightning fighter aircraft on its Izumo-class carriers.

On 8 August, a UK-operated F-35B landed on the flight deck of the Japan Maritime Self-Defense Force's (JMSDF's) second Izumo-class helicopter carrier JS Kaga .

It marked the first time that an operational F-35B had landed on an Izumo-class carrier, which took place during a trilateral exercise in the northern Philippine Sea involving naval forces from Japan, the UK, and US.

Kaga is the second of two Izumo-class helicopter carriers operated by the JMSDF, following JS Izumo , which was commissioned in March 2015. Kaga entered service in March 2017.

Originally designed as helicopter destroyers, both ships have since undergone major upgrades to support F-35B operations.

Izumo began its refit in 2021, followed by Kaga in March 2022. Enhancements include expanded flight decks, heat-resistant coatings, and landing aids to accommodate the F-35B's vertical lift and thrust.

The UK F-35B aircraft that landed on Kaga operated from HMS Prince of Wales , which is the marquee ship in CSG25. The carrier operated alongside Kaga and the US Navy's USS George Washington carrier strike group during the trilateral drills in the Philippine Sea.

In response to questions from Janes