WASHINGTON — The Air Force, disclosing a new problem with production of the MX nuclear missile, said Wednesday that it has begun penalizing Morton Thiokol because of "unsatisfactory workmanship practices" on the weapon's first-stage booster.
The service said the disciplinary measure entailed withholding 10% of the usual monthly contract payment made to the Chicago-based company for work on the first-stage rocket motors. That amounts "to approximately $1 million per month," the Air Force added.
The MX--called the Peacekeeper by the Reagan Administration--is a long-range, four-stage intercontinental ballistic missile capable of carrying 10 nuclear warheads. Its first stage is made by Morton Thiokol's Wasatch Operations in Brigham City, Utah, the same unit that made the solid-fuel boosters for the ill-fated space shuttle Challenger.
The remaining rocket stages for the MX are made by other defense contractors.
An Air Force statement said the penalty was imposed "because of unsatisfactory workmanship practices relating to the production of the Stage I rocket motor for the Peacekeeper missile system."
It added: "Deficiencies in contractor performance in this case are characterized by inadequate work instructions, poor workmanship and a lack of proper quality-control management during the production process for the Stage I rocket motor."
The Air Force asserted that, as of now, the problems at Morton Thiokol are not expected to affect the schedule for deployment of completed missiles. "However, internal Morton Thiokol production schedules have been missed, which, if left unchecked, could impact on future delivery schedules," it said.
At another point, however, the Air Force appeared to contradict the statement that only internal production schedules had been missed, saying that there have been "some short delivery delays."
The Air Force's public affairs office said it could not immediately answer such questions as when and how the service became aware of the workmanship problems or explain why it felt confident in saying that the problems "have had no impact on the quality of units already accepted by the Air Force."
Telephone calls to Morton Thiokol officials were not immediately returned.
The disclosure of the disciplinary move against Morton Thiokol followed similar action earlier this spring against Northrop, which makes the guidance system for the MX. The Air Force has so far withheld about $90 million in contract payments to Northrop because of delivery delays.
The Air Force acknowledged last month that because of the problems on the Northrop production line, seven of the 21 MX missiles installed at F. E. Warren Air Force Base, Wyo., have not been brought to alert status.
Responding to congressional concerns, the Air Force last week ordered a technical review by a scientific advisory board to ensure that the guidance units that have been delivered will work properly.
Northrop has acknowledged production delays but dismissed suggestions that the guidance units might malfunction.