Data indicates smoke alerts
CNN reported on Friday that flight data, from an automatic system called the Aircraft Communications Addressing and Reporting System (ACARS), said smoke alerts were triggered aboard the EgyptAir jet shortly before it crashed.
ACARS routinely downloads flight data to the airline operating the aircraft.
Two US officials told Reuters they could not confirm CNN's report. But they said an electronic sensor system had detected some kind of disturbance outside the jet around the time investigators believe it began falling from cruising altitude.
One of the officials said the disturbance outside the aircraft may have been caused by its sudden and rapid breakup, but it also could have been generated by some kind of mechanical fault or accident or a possible explosion or attack.
The officials asked for anonymity when speaking about the still-evolving investigation.
A screen grab of the flight data transmitted by ACARS to operators on the ground, published on the website of the aviation journal AVHerald.com, indicated failures in the jet's flight control system and alerts related to smoke in a lavatory and the avionics system, minutes before the crash.
The screen grab provided on the website showed only very terse messages sent from the aircraft, such as "SMOKE LAVATORY SMOKE," "AVIONICS SMOKE" and "F/CTRL SEC 3 FAULT."
The US officials said they could not confirm the authenticity the data, however, and EgyptAir officials could not be reached for immediate comment.
The plane vanished just as it was moving from Greek to Egyptian airspace control. Greek Defence Minister Panos Kammenos said it had swerved radically and plunged from 37,000 feet to 15,000 before vanishing from Greek radar screens.
Officials from a number of US agencies told Reuters that a US review of satellite imagery so far had not produced any signs of an explosion. They said the United States had not ruled out any possible causes for the crash, including mechanical failure, terrorism or a deliberate act by the pilot or crew.
Three French investigators and a technical expert from Airbus arrived in Cairo early on Friday, airport sources said.