Japan could arm its upgraded F-15Js with AAM-4B air-to-air missiles.

Japan’s Ministry of Defense has not discounted the possibility of arming the upgraded F-15Js with the indigenous AAM-4B air-to-air missile.

AAM-4B prototype (Picture source:Hunini )

The Mitsubishi AAM-4 (Type 99 air-to-air missile, is a medium-range active radar homing air-to-air missile, considered as modern beyond-visual-range missile developed in Japan and intended to replace the semi-active radar homing AIM-7 Sparrow missile in service. It has been operational since 1999.

The improved AAM-4B was the world's first air-to-air missile with an AESA radar seeker.The AAM-4B entered production in 2010 for service on Japan’s F-2 and F-15J fighter jets. However, it’s also a large weapon that is carried externally on a fighter’s fuselage (such as the F-35).