Officials halted their search this week for pieces of the ValuJet DC-9 that crashed a month ago in the Florida Everglades, saying they have recovered enough of the aircraft to determine what caused the accident.
Robert Francis, vice chairman of the National Transportation Safety Board, said workers recovered about 75 percent of the plane from the swampy crash site. But it will take months, he said, to reconstruct the parts that have been recovered and make a final determination.
Investigators are focusing on the forward cargo hold, which showed a considerable amount of fire damage.
More than 100 oxygen generators were packed in cardboard boxes and loaded in the hold, along with three airplane tires. The boxes were marked "empty," but officials believe the generators contained chemicals used to produce oxygen for on-board emergency face masks.
In its search, the NTSB has found significant pieces of evidence, including part of a tire with pieces of oxygen canisters embedded in it, an aluminum seat frame damaged by fire, and the cockpit voice recorder and the flight data recorder. Both instruments indicate a blast occurred before flight attendants reported a fire in the cabin.
Investigators also have pieces of a circuit-breaker panel - once suspected of sparking the blaze - that had been worked on before ValuJet's Flight 592 departed from Miami on May 11. None of the pieces, however, shows any signs of fire.
Meanwhile, reporters obtained a draft copy of a Federal Aviation Administration review of ValuJet. The FAA started a comprehensive review of the airline in February and stepped up its investigation after the crash.
The draft, completed May 5, indicates the FAA found at least 100 problems with ValuJet's performance, mostly maintenance related. An FAA official said that the findings "were borne out by preliminary raw data" and that ValuJet may already have made many of the corrections.
ValuJet issued a statement Tuesday, saying it is reviewing the FAA's findings. ValuJet president Lewis Jordan said he believes the airline has already addressed many of the issues raised by the FAA but will "voluntarily and enthusiastically correct all legitimate findings immediately."