A U.S. Air Force Global Hawk UAV based out of Guam flew over the damaged reactors at the Fukushima Daichi nuclear plant, in order to provide a more complete picture of what’s going on inside the facility.
The Global Hawk is an autonomous, jet-powered UAV with a sensor package that includes synthetic-aperture radar as well as electro-optical and infrared sensors with telescopic capability for high-resolution imagery.
The infrared sensors, which can detect heat, may be able to acquire images of the reactors showing which parts of them are at what temperatures, and repeated observations could provide critical data about the effectiveness of different attempts at cooling the reactor vessels and spent fuel pools.
The Global Hawk, with a 115-foot wingspan, is capable of conducting surveillance for 36 hours at a stretch at altitudes of up to 60,000 feet (18 kilometers). It can survey about 40,000 square miles (100,000 square kilometers) of terrain — the size of the state of Illinois — in a single day, entirely without human intervention: Once the robot receives its instructions, everything from taxiing to takeoff to data collection to landing is performed entirely autonomously.
The drone was originally designed for the U.S. Air Force as a long-duration surveillance aircraft, and has a history of successful and effective use in Iraq and Afghanistan, offering on-demand near real-time imagery that can’t be provided by satellites. The platform proved to be successful enough that Global Hawks have been adapted for climate monitoring and environmental mapping, and NASA has a pair of the UAVs that it’s using as technology demonstrators.