Egypt Official Says Plane Didn't Swerve, Plummet

CAIRO (CBSNewYork/AP) -- The head of Egypt's state-run provider of air navigation services says that EgyptAir Flight 804 did not swerve or lose altitude before it disappeared off radar, challenging an earlier account by Greece's defense minister.

Ehab Azmy, head of the National Air Navigation Services Company, told The Associated Press on Monday that in the minutes before the plane disappeared it was flying at its normal altitude of 37,000 feet, according to the radar reading.

He said "that fact degrades what the Greeks are saying about aircraft suddenly losing altitude before it vanished from radar.''

According to Greece's defense minister Panos Kammenos the plane swerved and dropped to 10,000 feet before it fell off radar.

Greek civil aviation authorities say all appeared fine with the flight until air traffic controllers were to hand it over to their Egyptian counterparts. The pilot did not respond to their calls, and then vanished from radars.

"There was no turning to right or left, and it was fine when it entered Egypt's FIR, which took nearly a minute or two before it disappeared,'' Azmy added.

Meanwhile, the French navy said Monday that one of its ships has arrived in the search area to help look for traces of Flight 804 and especially for its flight recorders.

The vessel is equipped with sonar that can pick up the underwater pings emitted by the recorders. It is specialized in maritime surveillance, and rescue and marine police missions.

An Egyptian government source told CBS News the black boxes have been located by their pings, but not yet recovered. However, there has been no official confirmation.

On Sunday, Egypt also sent a submarine to the Mediterranean to join the effort.

The search area is roughly halfway between Egypt's coastal city of Alexandria and the Greek island of Crete, where water is 8,000 to 10,000 feet deep.

A newly released audio recording captured a standard check-in between Flight 804's pilot and air-traffic control over Zurich, Switzerland.

Air Traffic Control: "EgyptAir 804 contact Padova 1-2-0, decimal 7-2-5, good night."

Pilot: "This is 0-7-2-5 Padova control. EgyptAir 804, thank you so much. Good day, er, good night."

Two and a half hours later, the aircraft began veering erratically before plummeting into the ocean.

Data published by an aviation industry website claims smoke was detected on board minutes before the plane went down. Aviation experts say that alone could rule out the possibility of pilot error.

"There is no human error that will trigger smoke alarms," said former pilot Alastair Rosenschein.

Airlines officials say it could take weeks to identify human remains that have been collected, adding to the grief of relatives still searching for answers.

Egyptian President Abdel-Fattah el-Sissi said mounting evidence is pointing to a sudden and dramatic catastrophe that led to the crash.

But el-Sissi is also cautioning against premature speculation.

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