The U.S. already has Global Hawks stationed at Andersen Air Force Base, Guam. The U.S. Air Force plans to expand the number of spy drones at Andersen and welcome Japan drones over the next decade as the Japanese military plans to buy its own drone fleet.
Japan's Self-Defense Force had planned to buy Global Hawks of its own before the deal was scuttled due to price concerns. The Japanese have remained confident in their plans to buy their own drones, especially as the Chinese naval fleet has stepped up their patrols throughout the Pacific.
Japanese military leaders currently fly the P-3C patrol aircraft to monitor Chinese naval movements. The investment in a Global Hawk or the U.S. Navy's version of the RG-4, the Triton, would be a considerable step up in Japan's intelligence, surveillance and reconnaissance capability.
U.S. and Japan air forces would share hangars and maintenance facilities for their drone fleets, according to the Japan Times report.
The U.S. Air Force's Global Hawk arrived at Andersen in 2010. It's the Air Force's largest drone, although it does not carry weapons like the Predator or the Reaper.
U.S. Global Hawks from Guam flew missions over Japan after the massive tsunami obliterated the country. The Global Hawks provided intelligence and imagery for humanitarian clean up.
Northrop Grumman unveiled the RG-4C Triton in June as part of the U.S. Navy's Broad Area Maritime Surveillance program. It's expected to fly a considerable chunk of it's missions over the Pacific monitoring the Chinese and North Koreans.