The tanker plane, the only one of its kind, is used to spray water onto other airplanes in flight to test how icy conditions affect them.
But in the next breath, he said Japan is studying the possibility of purchasing a tanker plane and helicopter-launching destroyers.
Last month, an American tanker plane conducted Japan's first air-to-air refueling.
Three helicopters and four tanker planes were being used to fight the Arcadia fire.
Buying more tanker planes, at $150 million apiece, could assure the needed number of sorties.
Before entering Iraqi air space, the F-16's topped off their fuel from a tanker plane.
"A fire in the reservation is so unexpected at this time of year that there are no tanker planes on call."
In addition, some aircraft were flown behind a tanker plane, which sprayed them with water to see how they would perform in such conditions.
Typically, tanker planes do not train regularly with the same group of fighters or bombers.
Over 2,000 firefighters fought this fire, along with 19 helicopters and five tanker planes.