Did relief pilot seize control from captain?

A team of experts continues to review the tapes at an NTSB lab in Washington to determine the relationship between mechanical events and the information on the cockpit voice recorder. Hall would not comment on the expected time line for completion of the analysis, but he remained optimistic that it would yield answers.

Language experts are also cautiously translating the contents of the cockpit tape, which are in Arabic, to determine whether or not the pilot's quote was, as is alleged, a prayer.

"Because of the quality and the extensive information contained on the flight data recorder, I am confident that many of the questions we have, you have and the individuals following this investigation around the world have, will be answered," Hall said.

The investigation team also includes representatives from Egypt, the Federal Aviation Administration, Boeing Co. and the engine manufacturer, Pratt & Whitney. Hall bristled at a question about how much influence Boeing has over the investigation.

"For over 30 years, our agency has proudly and independently investigated accidents," he said. "We understand fully the important responsibilities that this investigation brings to the NTSB, as well as the importance of the independence of this investigation for all of the parties who have an interest in it."

At each step, clues from the crash have only raised more questions and have done little to rule out any theory -- be it accident or sabotage.

The FBI has conducted interviews with EgyptAir staff and family members of the pilots, each of whom had recently passed mental and physical evaluations done by the airline. The Boston Herald reported last week that a crew member had placed an ominous call to his wife before takeoff, saying there was "something wrong with the plane," and that he was "very worried."

Meanwhile, in Egypt, conspiracy theories and angry suspicions are circulating about the crash.

The South China Morning Post reported Monday that EgyptAir officials are angry that the investigation has focused on the pilots' mental health, and that they believe the black-box data "points to sabotage." The report quotes Essam Ahmed, former head of EgyptAir's committee in charge of investigating crashes, as saying that the pilots were trained to glide an aircraft down if the engines stopped. Ahmed suggested the possibility that a bomb was planted in the toilet behind the cockpit, a scenario that the U.S. investigation has not ruled out.

On Tuesday, the AP quoted veteran EgyptAir pilot Yusry Hamid rejecting pilot sabotage as the cause of the crash. Hamid has flown the New York-to-Cairo route often and said of the pilots, "I know them very well." He suggested that co-pilot Anwar was responding to an emergency caused "possibly by an explosion, possibly by a missile or some mysterious thing." As for the widely reported prayer, Hamid insisted, "Any pilot who sees he is heading toward trouble will say religious prayers, whether he is a Muslim or a Christian."

Hamid also provided an explanation for why the engines were shut off, saying the pilots were "trying to reduce the speed" and prevent the plane from collapsing. Shortly after engines were shut off, the plane rose from 16,000 feet to 24,000, before it stalled and fell into the Atlantic.

The Middle East Times reports that the editor in chief of "conspiracy-minded" official Egyptian newspaper Al Gomhuriya published an editorial on Nov. 6 accusing the U.S. military of bringing down the plane with missiles.

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