U.S. offers unmanned chopper to help remove Fukushima spent fuel

The U.S. government has told Japan that it can use a U.S. unmanned cargo transport helicopter to set up cranes to remove spent fuel rods from storage pools at the crippled Fukushima nuclear power plant, Japanese and U.S. sources close to the matter said Saturday.

The K-MAX helicopter, developed jointly by Lockheed Martin Corp. and KAMAN Aerospace Group of the United States, is being considered to set up the huge cranes.

The proposal has been communicated to the unified command headquarters set up by the Japanese government and Tokyo Electric Power Co. to deal with the nuclear crisis. Japan has not yet made a formal response to the proposal.

Since the ground positioning system-equipped chopper can be operated remotely, it would enable emergency workers to implement restoration work even in areas contaminated by high levels of radiation, they said.

TEPCO has been cooling down the spent fuel storage pools on the fifth floor of the reactor buildings by pumping water using a truck-mounted concrete pump.

Spent nuclear fuel is usually transported away from nuclear plants inside steel casks after being cooled in storage pools for a few years.

Since the original fuel transportation equipment at the Fukushima plant's reactor buildings was damaged by hydrogen explosions following the March 11 quake and tsunami, TEPCO is considering employing a huge crane to lift casks into the storage pools so that spent fuel rods can be placed in them.

The United States has proposed transporting partially assembled cranes to the plant using the unmanned helicopter. It has also proposed starting full-fledged installation of the cranes after radiation levels fall.

The proposal was originally conveyed by Adm. Robert Willard, commander of the U.S. Pacific Command, at a meeting in late March with his Japanese counterpart Self-Defense Forces Chief of Staff Ryoichi Oriki, the sources said.

The U.S. side is ready to transport the unmanned helicopter by plane from the United States to the Matsushima base of the Air Self-Defense Force in Higashimatsushima, Miyagi Prefecture, they said.

The K-MAX helicopters belong to the U.S. Marine Corps. The remote-controlled choppers were introduced by the U.S. military after a number of manned helicopters were shot down by insurgents in Afghanistan.

The improved version of the K-MAX can lift around 1.4 tons.