Why Japan chose the F-35

A few weeks back, Flight Global ran an extensive article discussing Japanese air power and how its qualitative edge had eroded since China had begun it's military modernization in earnest.  Until then, Japan's fighter fleet was qualitatively superior to the Chinese.

However, as that began to change, the Japanese began looking at replacements for it's aging fighter fleet.  Initially it focused mainly on air superiority.  Of course the F-22 was out of the running, so Japan began by considering Boeing F/A-18E/F Super Hornet and Eurofighter Typhoon in its F-X competition for 42 aircraft.

But then something happened to change that:

In January 2011, the Chengdu J-20's maiden flight revealed China's ambition to further enhance the quality of its air force. Although little is known about this type's radar cross section, avionics or intended mission - pure fighter or long-range strike aircraft - the J-20 raised the spectre of China deploying a credible stealth aircraft by 2018. In mid-September, another advanced aircraft appeared at the Shenyang Aircraft Corporation airfield bearing all the characteristics of a stealthy airframe. Whether the type, variously designated the J-21, J-31 or F-60, is a rival programme to the J-20 or will be developed at the same time is impossible to know. Nonetheless, both programmes show how serious China takes air force modernisation. 

Suddenly, Japan was catapulted into the 5th generation.  It's main rival and potential enemy was developing not one but two 5th generation aircraft.

The focus in Japan's F-X competition shifted to stealth and advanced capabilities.  And the only aircraft available that provided both was the F-35.  There were obviously other considerations as well, but in the end, the F-35 was their fighter of choice.

Japan will also be working on its own version of a 5th generation fighter.  In the meantime, the F-35 will be the 5th generation mainstay for the Japanese Air Force.

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