They will stay in the country until October and will be used to watch North Korean nuclear bases and Chinese naval operations.
The units at Misawa Air Base will be operated from the ground until it reaches a certain height after takeoff. They will then be operated from Beale Air Force Base in California via satellite. They used to have drones stationed in Guam but the weather there often interrupted or scrubbed missions.
Japan currently monitors North Korea's nuclear activities using satellites but the surveillance is limited as they have restricted time frames in orbit. In addition to using them to monitor nuclear activities, they also plan to keep an eye on China's activities in the South China Sea.
"The Global Hawk provided us with a wealth of data, including surveillance of crippled reactors at Tokyo Electric Power Co.'s Fukushima No. 1 nuclear power plant," said a senior Japanese Self-Defense Force official. "The device will be effective in surveying the activities of North Korea and the Chinese military."
The Japanese transport ministry issued a warning to civilian and military aircraft to avoid collisions with the unmanned vehicles as they are deployed in late May.
Japan plans to buy three of their own Global Hawk drones in the future.