MIAMI (AP) _ Even as hearings opened last month into the crash of ValuJet Flight 592, whistleblowers at SabreTech were complaining that a bent pressure probe from a jet was straightened and reinstalled instead of being replaced as required by Boeing.

The Federal Aviation Administration and the Transportation Department inspector general's office are investigating the complaint, as well as other allegations against the Arizona-based maintenance company.

``Clearly, the investigation isn't limited,'' Bob Ropelewski, a spokesman for the Federal Aviation Administration, said Thursday. ``We wouldn't expect that they handle things differently from one customer than they would for another.''

A load of oxygen generators that was improperly labeled and packaged by SabreTech at its Miami maintenance hangar are suspected of causing the fire that crippled the ValuJet flight on May 11. The plane crashed into the Florida Everglades, killing all 110 people on board.

SabreTech has admitted that mechanics signed false paperwork indicating that they had installed plastic safety caps on the generators. ValuJet wasn't authorized to carry the generators as cargo, even if they were capped.

The more recent incident involved a 737-500 that was managed by the leasing firm General Electric Capital Aviation. It was undergoing maintenance last month in Orlando in preparation for delivery to Jet Airways of India, according to accounts that SabreTech workers and executives gave to the trade magazine Aviation Week and Space Technology.

On Nov. 1, a mechanic removed a pressure-sensing probe from the fan frame and discovered it was bent. It was straightened in SabreTech's machine shop, and the mechanic was told to reinstall it.

The mechanic and others were alarmed by the fix, but several supervisors, including the facility's chief inspector, said it was acceptable.

The mechanic put the part back but refused to sign the job card taking responsibility for the work. The lead mechanic signed instead, and the chief inspector stamped the card to indicate the work had been inspected and that it was in accordance with the maintenance manual put out by Boeing, the plane's manufacturer.

Still concerned, two workers not involved with the reinstallation wrote an anonymous letter Nov. 18 to general manager Robert Griswell, the top company official in Orlando.

That same day, the ValuJet crash hearing opened in Miami. SabreTech President Steven Townes defended his company's work, while pledging lessons had been learned from the crash.

In response to the anonymous letter, Griswell called a staff meeting Nov. 22 to say SabreTech was fully committed to safety, but he also concluded the probe repair was acceptable.

The next day, the mechanic who had reinstalled the probe told the pilots who were to fly the plane of his concern. He also called the FAA's safety hotline.

The FAA's principal maintenance inspector for SabreTech's Orlando shop showed up the next day, a Sunday. On Monday, Michael Block, the quality assurance director for SabreTech, reviewed the work and found there was nothing to indicate the FAA official approved the repair.

In addition, Block said, the lead mechanic and chief inspector said the work had been done in accordance with the maintenance manual, when it had not. In fact, the shop didn't even have a complete manual for the engine. At his direction, the shop contacted Boeing, which said that the part must be replaced.

SabreTech has since fired the lead mechanic who signed off on the work and the chief inspector who approved the repair has resigned, company spokesman Jim Grandone told The Associated Press on Thursday.

In addition, the mechanic who balked at reinstalling the straightened probe _ and who later called the FAA _ was fired for allegedly falsifying paperwork on a different job, a fan-blade lubrication. Also fired were another mechanic who worked on the fan-blade and the inspector who approved their work.

One other lead mechanic has also been fired, Grandone said.

``The people who were terminated took unauthorized actions not sanctioned by the repair station, and the reaction was swift and permanent,'' he said.

Townes, who had assured investigators that policies and training had been overhauled in response to the crash, on Dec. 22 ordered employees in Orlando to attend special training seminars through Jan. 1.

``There will be no one who can in any way misunderstand that we have zero tolerance for not following procedures,'' Grandone said.