WASHINGTON The death plunge of EgyptAir Flight 990 apparently began as a ''controlled descent'' in the course of an otherwise routine flight, federal investigators said Wednesday.
The initial information from the Boeing 767's battered flight data recorder intensified the urgency of finding the second of the plane's two ''black boxes,'' still on the bottom of the Atlantic. The readout from the cockpit voice recorder could explain why the plane's autopilot disconnected, under what circumstances the plane began its dive and what caused it to pull out and climb before going into a final, fatal fall.
National Transportation Safety Board Chairman Jim Hall, whose agency is leading the investigation, called the new information ''preliminary'' and cautioned against drawing sweeping conclusions. But the data indicate that the plane was not spiraling out of control.
''We cannot expand on the information we have for you at this time,'' Hall said. ''We await information off the cockpit voice recorder ... that can help us put this information in context.''
Hall knocked down one of the early crash theories, that a thrust reverser designed to slow a plane down once it lands might have accidentally deployed in flight. ''There is no evidence (of that) in the data we have,'' he said.
NTSB officials say they are considering every possible explanation, including equipment problems, human error, or a combination of the two. Also among the possibilities is a hostile takeover of the flight deck, a bomb or some other criminal act. The FBI is aiding in the investigation, but the safety-oriented NTSB remains in charge.
The Halloween morning tragedy took the lives of all 217 people aboard the jetliner, which began its flight in Los Angeles and stopped to pick up passengers in New York before taking off for Cairo.
NTSB and Egyptian officials on Wednesday displayed the flight data recorder, still dripping water, before a roomful of cameras and reporters in Washington. Its bright orange outer casing was battered, but the inner ''crash case'' containing the digital recorder itself was in good shape.
The flight data recorder was designed to capture at least 55 types of information including the plane's altitude, speed, spin and roll, if and when electrical power was cut off, and how the autopilot functioned.
Searchers have isolated a signal from the plane's cockpit voice recorder and are using underwater cameras and lights to try to locate it.