BRIGHAM CITY, Utah — Nearly 100,000 pounds of rocket fuel in an MX missile section burst into flames at a Morton Thiokol Inc. plant Tuesday, killing five workers when fire consumed the building, officials said.
The fire, at the company's Wasatch Operations, 25 miles west of Brigham City, was the firm's fourth major accident in four years, state records indicate. None of the earlier accidents involved fatalities.
The cause of the fire was not determined, but the workers were believed to have been removing a casting from the center of the missile motor's solid fuel when the fire erupted, officials said.
"This is a normal operation for all rocket motors. There was nothing unusual or novel about it," said Phillip R. Dykstra, vice president and general manager for strategic operations at the plant.
The four-stage MX, an intercontinental ballistic missile, has a solid-fuel first stage, all of which burned before fire crews extinguished the blaze.
Tom Russell, vice president of corporate development and strategic planning for Morton Thiokol, said the fire occurred about five miles north of test bay T-24, where six days earlier Morton Thiokol conducted its second full-scale test firing of the redesigned space shuttle booster. The shuttle booster facilities were not damaged in Tuesday's fire.