Union tells NASA to halt work on Pluto spacecraft

Boeing workers fret about safety

The union representing striking Boeing machinists asked NASA on Monday to halt work on a plutonium-powered spacecraft, claiming it is irresponsible to allow five replacement workers to complete the job.

NASA said the managers and supervisors have the skills needed to complete the work safely, and the agency intends to press ahead with plans to launch its Pluto-bound New Horizons spacecraft next month.

The replacement workers "are certified, have extensive previous experience and have met the safety criteria," NASA launch services manager Steve Francois said. "No exceptions to either safety or quality assurance have been made and none are planned."

The New Horizons mission must be launched during a time-critical 35-day window that opens Jan. 11. A delay past Feb. 14 would force NASA to postpone the launch until early 2007, the next time the planets are aligned properly for the trip.

The mission is one of four that Delta rocket machinists were working on before they went on strike Nov. 2. Work on the other missions ceased then.

The grounded missions include launch of an advanced weather satellite for the National Oceanic and Atmospheric Administration at Cape Canaveral Air Force Station.

On hold at Vandenberg Air Force Base in California are a NASA atmospheric science mission and a classified flight for the National Reconnaissance Office.

"If it's not safe to work on all the other projects with replacement workers, it's irresponsible to continue with New Horizons," said Robert Wood, a spokesman for the International Association of Machinists and Aerospace Workers.

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