As Delta Airlines complied with a federal order to re-inspect over one hundred aircraft Tuesday, thirteen suspect parts from MD-80 series planes were headed for a federal aviation safety lab in Washington for study.
The parts were detected in inspections of MD-80 series and other aircraft ordered by the FAA Friday in the wake of the crash of Alaska Airlines Flight 261.
The second round of Delta inspections, CBS News Transportation Correspondent Bob Orr reports, was ordered by the FAA so inspectors could confirm that an upper stop on the jackscrew, which limits the downward travel of the stabilizer, was properly adjusted.
Delta spokesman John Kennedy said all 136 MD-80 and MD-90 planes had been re-examined by 8 a.m. and were back in service. Delta had had until 9 p.m. Tuesday to re-inspect all the planes. As a result of all the inspections, one jackscrew was replaced and one was re-lubricated, Kennedy said.
Airlines on Friday were given 72 hours to inspect the stabilizer control mechanism in almost 1,100 planes after problems were found in that part of the Alaska Airlines MD-83 that crashed Jan. 31, killing all 88 people aboard.
Also on Monday, the FAA said 13 suspect jackscrews had been removed from planes and sent to Washington, where the FAA was to turn them over to the National Transportation Safety Board for analysis.
The investigation into the crash of Alaska Airlines Flight 261 is focusing on the jackscrew and gimbal nut, which work together to move a planes tail wing up and down, controlling an aircrafts horizontal movement.
Flight 261's jackscrew was worn and wrapped in a metal ribbon that came from the gimbal nut. If the nut was stripped bare before the crash, investigators believe the horizontal stabilizer may have malfunctioned.
Regarding the parts sent to Washington, NTSB spokesman Terry Williams said agency technicians are studying the parts for wear and signs of damage to determine if recommendations are needed for more frequent maintenance and parts inspection.
The NTSB also is studying maintenance records of this type of plane.
Investigators revealed Monday that more than two years ago, Alaska Airlines mechanics spotted jackscrew problems in the plane that crashed. On September 29, 1997, mechanics at Alaska Airlines' Oakland, Calif. facility noted the nut on the jackscrew assembly was worn. Plans were made to immediately replace it.
But the next day, September 30, records show the nut was checked again and found to be "within the specified tolerances". In fact, it was inspected and "cleared" five times and never replaced before the crash.
However, the NTSB has not yet determined that the jackscrew caused the Alaska Airlines crash. "The significance of this information is continuing to be evaluated by the NTSB. No determination has been made as to whether this information has any bearing on the accident," the safety board said in a statemen.
Over 1,000 planes were inspected over the weekend, with a mere handful requiring repairs. Former National Transportation Safety Board Chairman Jim Burnett said even a very few problems was"disturbing."
"Even one [plane] is significant if it is a problem that might bring down an airplane," Burnett told the CBS News Early Show. "So I think we have to take all of this very, very seriously."
In addition to ordering the urgent inspections, the FAA increased the frequency of regular jackscrew inspections from every eight months to about every three months.
The military has also been checking its C-9 planes, the military version of the DC-9. No problems have been found during inspections of the 29 C-9 aircraft operated by the Navy and Marine Corps, said Navy spokeswoman Lt. Elizabeth Zimmermann.
As the probe into the cause of the crash continued, efforts to recover the bodies of victims moved ahead slowly. The Ventura County medical examiner reported Monday that 47 bodies from the downed plane had been positively identified, and families were being notified.
©2000 CBS Worldwide Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report
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