BRIGHAM CITY, Utah -- Morton Thiokol Inc. executives said Wednesday experts have begun an investigation that could take several weeks to determine the cause of a rocket propellant fire that killed five workers in an MX missile facility.
The rocket manufacturer, meanwhile, lowered its flags to half staff in memory of the four workers killed instantly Tuesday and one who died 11 hours later after suffering burns over 95 percent of his body.
The deadly fire was the worst accident in the company's 30-year history in Utah.
The fire erupted about 6:20 a.m. MST at Morton Thiokol's Wasatch Operations plant, 75 miles north of Salt Lake City, where booster rockets for space shuttles are also made. Officials said no shuttle facilities were damaged.
Thiokol officials said it could take several weeks to determine the cause of the blaze, which broke out as workers were removing tooling equipment used to cast, or shape, solid propellant in the first stage of the MX -- the Air Force's most powerful intercontinental ballistic missile, which President Reagan calls the Peacekeeper.
'It's the only facility equipped to do Peacekeeper casting at this moment,' said Capt. Louis Figuerosa of the Air Force Systems Command, which oversees research and development of weapons systems.
'However, Morton Thiokol does have other casting facilities that I'm told with some modifications could be set up for the Peacekeeper stage one casting, and keep the Peacekeeper program right on track.'
Morton Thiokol spokesman Ed Snow said two other facilities were available to produce the first-stage MX missiles.
The defense contractor has been delivering two first-stage missile motors a month to the Air Force, Snow said, but beginning next March production will be reduced to one per month.
Joining in the probe were Utah Occupational Safety and Health Compliance investigators, said supervisor Don Anderson.
'We'll try to put together what happened and why,' Anderson said, adding the probe will take 'a couple of weeks' to conduct interviews and reconstruct procedures used in loading propellant into the missile.
Meanwhile, NASA engineers were examining data from a Dec. 23 test firing of a redesigned Thiokol shuttle booster rocket that officials said showed the nozzle system failed.
The test initially was called a success, but NASA said late Tuesday post-firing analysis of the big nozzle that helps steer the rocket showed a section of a ring assembly used to anchor it to the casing had come apart, which could delay for several months the first post-Challenger shuttle flight.
Morton Thiokol stock Tuesday closed at $40.75 Tuesday, $1.125 lower than at the end of Monday's business day after word spread about the accident.
'Fundamentally, what we think happened was that through some operation associated with removing the tooling from the motor, the propellant ignited, and there's approximately 100,000 pounds of propellant in the motor and that caused a severe fire causing the destruction of the building,' said Philip Dykstra, Morton Thiokol's director of Strategic Operations who will head the company's investigation.
One engineer who requested anonymity speculated that removal of casting equipment may have set off sparks, igniting 50 tons of the propellant that burns at about 5,000 degrees Fahrenheit. Another possibility, he added, is that material used to shape the fuel may have not dried sufficiently, allowing unstable nitroglycerin to set off the rubbery material.
'We are meeting daily with the investigative team and they are being very methodic about this and systematic, so they don't want to speculate, they want to find out,' said Snow.
'We have Air Force safety people who work here at the plant, and they're already involved in the investigation. Next week, the Air Force is going to be flying in some other safety experts to assist in the investigation.'
