How flight 9268 crashed in Egypt: Here's what we do and do not know

Aviation experts are investigating what caused a Russian airliner to crash in the Sinai peninsular on Saturday, killing all 224 people on board.

Flight FK9268 had left Egypt's Sharm el-Sheikh airport in the morning heading for St Petersburg but lost contact with air traffic controllers less than 30 minutes into the trip.

What happened to the plane?

No conclusions can be drawn until further investigations take place. Egyptian investigators have found both black boxes, one for cockpit voice recordings and one on for flight data, the Egyptian Civil Aviation Minister said. These will allow investigators to determine what happened in the plane's last moments. An official from the Egyptian Aviation Incidents Committee said the pilot had radioed to report technical difficulties and was planning an emergency landing at the nearest airport before losing contact with air traffic controllers. Kogalymavia, the company that owns Metrojet, said the plane had been fully serviced, appearing to suggest that any technical difficulties, if there were any, were not visible on the ground.

Did the plane's age play a factor?

Manufactured in 1997, the plane had accumulated 56,000 flight hours during nearly 21,000 journeys before yesterday's crash. It had been operated by Metrojet since 2012. Oksana Golovin, a spokeswoman for Kogalymavia, said the plane was in "full working order" and being operated by an extremely experienced crew. She told a press conference that the pilot had 12,000 hours of flying experience.

Was the plane shot down?

While an Isis affiliate appeared to take responsibility for bringing it down, no evidence was offered to back this up, and the group is not known to have the weapons capability to do so at the height the plane was apparently cruising. The Russian transport minister, Maksim Sokolov, told Interfax news agency that "such reports cannot be considered true".

What are the repercussions?

Other passenger flights have already been affected by the crash. Germany's Lufthansa airline said it will no longer fly across the area "as long as the cause of [the] crash has not been clarified". And Air France has said it will also avoid the area pending the outcome of the investigation "as a precaution, until further notice".

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