The Japan Maritime Self-Defense Force (JMSDF) released new photos of the JS Kaga (DDH 184), which had been undergoing major modifications that will allow the Izumo-class helicopter carrier to operate with the Lockheed Martin F-35B.

In a post to X, the social media platform formerly known as Twitter, the JMSDF's Escort Flotilla Four announced that the refit has been completed and the flattop is now undergoing sea trials.

JS Kaga underwent the year-long modifications at the JUM shipyard near her home port at the JMSDF Kure Naval Base, where the Escort Division Four of the Escort Flotilla Four is also based.

According to a report from Naval News, the transformation was largely completed earlier this year. "The bow section of its flight deck had been modified from a trapezoid into a square shape, similar to that found on the US Navy's Wasp-class and America-class amphibious assault ships."

The modifications were far more than cosmetic and included reinforcing the flight deck to support additional weight, placing additional guidance lights, drawing the yellow lines on the flight deck necessary for launching and landing F-35Bs, and fitting the ship with heat-resistant deck spots for vertical landings. The second and final modifications, which are expected to be made during Kaga's next overhaul beginning at the end of fiscal year 2026 (FY26), will reportedly include changes to the ship's interior compartments.

The JMSDF has also been modifying Kaga's sister ship, JS Izumo, as part of naval expansion. Beginning next April, the lead vessel of the Izumo-class will begin modifications of the bow section of its flight deck. The helicopter carriers measure over 800 feet (248 meters) in length and displace 27,000 tons, and while far smaller than the U.S. Navy's 100,000-ton nuclear-powered supercarriers, these are still the largest Japanese military ship built since the Second World War, can carry up to 14 helicopters.

Preparing for The F-35

In November, a delegation from the JMSDF traveled to Norfolk, Virginia, to observe portions of the F-35 trials on the Royal Navy's aircraft HMS Prince of Wales (R09) to help them prepare for carrying out the same drills in 12 months with the Kaga.

The island nation is expected to receive six F-35Bs in 2024 from a total order of 42 aircraft and a provisional F35B squadron will be established the same year.

"Japan is acquiring the most F-35s of any international customer," Lockheed Martin noted on its website.

Japan Will Again Operate Sort of Aircraft Carriers

As previously reported, Tokyo hasn't operated actual aircraft carriers since the end of the Second World War, but in August 2013, Japanese officials announced that its two helicopter destroyers would be modified for use in national defense – notably to confront China's naval expansion.

However, the Japanese decision to modify the ships had been seen with caution in China, which has described it as an aircraft carrier in disguise and suggested that it could be used to launch other fixed-wing aircraft.

Japanese military sources have confirmed that the possibility of operating such fixed-wing aircraft had been incorporated into its design. However, that fact was not made public as Article 9 of the Japanese Constitution, which was adopted after World War II prohibited Japan from possessing offensive military weapons including aircraft carriers.

The Japanese Defense Ministry's recent record budget request of $52.9 billion will go toward ongoing naval upgrades as well as the procurement of F-35 jets and cruise missiles that can strike deep into enemy territory, Newsweek reported.

First Tests Completed

In October 2021, months after it completed its first phase modifications, a United States Marine Corps F-35B conducted the first-ever takeoff and landing test on JS Izumo.

The event marked the first time since the days of the Imperial Japanese Navy that a fixed-wing aircraft took off from a Japanese vessel. It is also notable that the Imperial Japanese Navy also operated an aircraft carrier named after the Kaga Province – and it was a Tosa-class battleship converted into a carrier.

Although it won't have as sizeable a fleet as it had during the Second World War, the JMSDF will operate with far more advanced aircraft and could help serve as a deterrent to China in the Indo-Pacific region.

Author Experience and Expertise

Peter Suciu is a Michigan-based writer. He has contributed to more than four dozen magazines, newspapers, and websites with over 3,200 published pieces over a twenty-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a Contributing Writer for Forbes and Clearance Jobs. You can follow him on Twitter: @PeterSuciu.