Tanker 910 is a converted McDonnell Douglas DC-10 aircraft used for fighting wildfires, typically in rural areas. The turbofan-powered former airliner carries up to 12,000 US gallons of water or fire retardant in an exterior belly-mounted tank, the contents of which can be released in eight seconds.
The water or retardant is carried in three center-line belly tanks. The tanks have internal baffles to prevent fluid shift (and consequent shift in center of gravity) while in flight, and sit with a 15-inch ground clearance. All three tanks can be filled simultaneously on the ground in eight minutes. The retardant is gravity-fed out of the tanks, and the entire load can be dumped in eight seconds, although the actual drop rate is computer controlled by the flight crew in order to produce the desired retardant spread over the fire lines. The aircraft is capable of applying a line of retardant 300 ft wide by 1 mile long.