The U.S. attorney's office in San Francisco has reopened its criminal investigation of the crash of an Alaska Airlines jetliner off the coast of Ventura County three years ago, sources close to the case said Thursday.
The investigation had been suspended until the National Transportation Safety Board concluded its investigation of the crash, which killed all 88 aboard Flight 261 from Puerto Vallarta, Mexico, to San Francisco on Jan. 31, 2000.
The NTSB issued its final report on the crash in December, saying the MD-83 jet went into an uncontrollable dive after the failure of the horizontal stabilizer, the wing-like portion of the tail that controls the up-and-down pitch of the nose.
The stabilizer problem was blamed on the failure of a key component called the jackscrew assembly. The jackscrew is a large, threaded bolt that raises and lowers the leading edge of the stabilizer.
The jackscrew was not lubricated adequately, the NTSB said. The investigators said the lack of lubrication, which stripped the threads from a nut that held the bolt, was the immediate cause of the crash.
The NTSB report cited widespread maintenance deficiencies at Alaska Airlines and lax oversight of those maintenance operations by the Federal Aviation Administration as underlying factors in the accident.
The U.S. attorney's investigation is to determine whether that lack of lubrication is the result of a deliberate decision not to perform necessary maintenance or simply the result of poor judgment and oversight.
The NTSB said American Airlines, which requires frequent lubrication of the jackscrews, had had little trouble with its dozens of MD-80 series aircraft.
But Alaska Airlines sought -- and the FAA approved -- less frequent lubrication of the jackscrews in its planes. Alaska Airlines also obtained FAA approval for longer intervals between the inspection of its jackscrews.
About two years before the crash of Flight 261, the U.S. attorney's office began a grand jury investigation into the maintenance practices at Alaska Airlines' repair facility in Oakland. After the crash, the investigation was expanded to include the crash of Flight 261.
In December 2001, the U.S. attorney's office said the maintenance activities at Oakland did not warrant further investigation or the filing of criminal charges. The part of the probe pertaining to Flight 261 was put on hold until the NTSB issued its report.
Both the airline and the U.S. attorney's office declined comment Thursday, saying they were precluded by law from talking about the case.
Times staff writer Ricardo Alonso-Zaldivar contributed to this report.