Japan, once a world leader in aircraft carriers, is preparing to wade back into the world of fixed wing aviation. The Pacific country, which swore off flat-tops in the aftermath of World War II, is preparing to reverse decades of government policy and add fighter planes to so-called “helicopter destroyers" to counter Chinese air power.

At the time of the attack on Pearl Harbor in December 1941, Japan was an aircraft carrier superpower. Japan had more carriers than any other country, including the United States, and its pilots were trained to a high standard by years of war. A little more than four years later, all but one of Japan’s carriers were on the bottom of the ocean, and most of the pilots had been killed in battle.

Japan, which reinvented itself under American control as a pacifist country, swore off “offensive” weapons of war such as marines, bombers, and aircraft carriers. Despite this, for decades Japan’s navy, the Maritime Self Defense Force, quietly plotted a return to naval aviation. Over the years it has gradually built ships with increased aviation duties in mind, from destroyers with large helicopter landing decks to tank landing ships with full-length flight decks.

JS Izumo with embarked SH-60 helicopters. Getty Images

Japan’s latest aviation ships, the Izumo class “helicopter destroyers,” are aircraft carriers in all but name. Izumo and her sister ship Kaga resemble miniature carriers, with an island, full-length 814 foot long flight deck, a spacious hangar, and elevators that shuttle aircraft between the flight deck and the island. At 27,000 tons, the ships are roughly a third the size of the U.S. Navy’s Ford-class supercarriers.

Izumo and Kaga were built to embark with up to 14 SH-60K Seahawk anti-submarine helicopters and V-22 Osprey tiltrotor transports, sweeping neighboring waters of enemy submarines or acting as lily pads for marines flying Ospreys to distant islands in the Japanese archipelago. Although both ships could theoretically accommodate the vertical takeoff and landing version of the Joint Strike Fighter, the F-35B, it was thought that modifying the ships for the stealth fighter was politically risky and too expensive.

However, according to Japan’s Kyodo news service, the Japanese government is “mulling” a plan to purchase F-35B fighters and convert Izumo into a full-fledged aircraft carrier. Tokyo already plans to purchase 42 F-35As, the version of the jet that equips the U.S. Air Force, and could either change its order to include some F-35Bs or simply order more jets.

F-35B Joint Strike Fighter. Steve Thorne Getty Images

If the Japanese government goes through with the proposal, the Izumo carriers will need to head back to the shipyard at Yokohama for major design changes. The flight deck will need a new thermotolerant coating to withstand the extreme heat of the F-35B's exhaust during takeoff and landing. The bow-mounted Phalanx close-in weapon system, designed to destroy incoming missiles, will probably have to be removed as it is a hazard to larger aircraft.

Down below, the Izumo will need to set aside room in the hangar for more aviation fuel and jet-launched weapons such as the AIM-9X Sidewinder, AIM-120 AMRAAM missiles, and JDAM satellite-guided bombs. Izumo will also need to install a seagoing version of the Automated Logistics Information System, or ALIS for short, that coordinates repairs and spare parts for the F-35 fleet worldwide. Setting aside all of that space will result in a smaller hangar.

The conversion process from “helicopter destroyer” to aircraft carrier is an expensive proposition. Izumo could probably carry about ten F-35Bs at a time, and a dozen aircraft to include spares would cost about $1.4 billion. Converting the ship itself could cost another half a billion dollars, and the entire process could cost approximately 5 percent of Japan’s annual defense budget. It looks likely that Tokyo will convert both Izumo and Kaga, with a total overall cost of about $4 billion. That’s a lot of money just to put 20 fighter planes to sea, and a tough pill to swallow for a country that spends just over 1 percent of its GDP on defense and is mired in public debt.

A U.S. Marine Corps F-35B lands on the USS Essex. U.S. Marine Corps photo by Lance Cpl. Roderick Jacquote

From Japan’s perspective, however, it has little choice. Japan is particularly nervous about the increasing number of Chinese military flights at the southern end of the Japanese island chain, closer to Taiwan than Tokyo, where Chinese Air Force fighters and bombers have repeatedly flown past the Japanese islands. There’s also the matter of the Japanese-held Senkaku islands, claimed by China as the Diaoyu islands, in the nearby East China Sea.

While China has several major air bases within range of both regions, Japan has a single air base on the island of Okinawa that also doubles as a regional civilian airport. Naha Air Base, home to approximately 40 Japanese F-15J fighters, bears the brunt of responsibility responding to Chinese air incursions. In wartime, the airfield would likely be pounded flat by Chinese ballistic missiles, leaving the southernmost part of Japan without air power. Adding an aircraft carrier would allow Japan to station a floating airfield wherever it wanted, boosting regional defenses.

But what about Japan’s prohibition on aircraft carriers? Legally, the prohibition is actually against “attack aircraft carriers” meant to project offensive air power against another country. The Izumo class armed with F-35Bs would technically be “defensive” aircraft carriers meant to protect Japanese airspace.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io