The development came after investigators said that they had located the wreckage of Flight 990 about 250ft down on the floor of the Atlantic, 60 miles south of Nantucket Island. They also said that the "ping" signal from its data and voice recording devices had been detected.
A CNN correspondent was told that a crew member mentioned the difficulty with the thrusters during the plane's turnaround at Los Angeles airport on Saturday, but it was not clear whether a formal report was made, or whether the crew member had made a passing observation about something regarded as an irritation rather than a fault. Until now, the only work known to have been done on the plane at Los Angeles was a tyre change, which contributed to the three hour delay at New York's Kennedy airport that evening.
The official report on the Lauda Air crash concluded that the disaster was probably caused by the activation of an engine thrust reverser in mid-flight. The thrust reversers are supposed to be deployable only when the plane is on the ground. Transcripts of the cockpit conversations showed the crew commenting on the intermittent flashing of the thrust reverser warning, which was dismissed as a minor electrical fault possibly attributable to moisture.
When the reverser suddenly deployed, the recording registered one of the crew swearing, the repeated crunch of metal, then nothing, as the plane dropped to the ground.
Among the similarities between that disaster and the Egyptair crash are the point and altitude in the flight, the speed of descent, and the lack of any communication from the pilot that there was a problem. As was reported yesterday, the Egyptair 767 came off the Boeing production line immediately before the Lauda Air plane, when the company was in the throes of a labour dispute.
Changes in the thrust reversers were required following the Lauda Air crash. Egyptair said the mandatory adjustments were made, but not by Boeing.