What caused Egypt crash? Russian airline claims 'external' factor

With investigators still combing through the wreckage of the Metrojet flight, no cause has been ruled out, including mechanical failure or a bomb.

Officials from the operator of the doomed Russian Metrojet flight that crashed in the Sinai Peninsula over the weekend have denied that the plane suffered from a mechanical failure, claiming that the plane was brought down by "an external impact."

But investigators are still combing through the wreckage, and have not yet publicly ruled out any cause for the crash, including a mechanical accident or terrorist act.

The Associated Press reports that Viktor Jung, a Metrojet deputy director general, said at a press conference Monday that the crew of the doomed flight "became incapacitated" soon after the plane began to slow and fall from the sky, and that there was not "a single attempt to get in touch [with air traffic control] and report the situation on board." Another Metrojet official, Alexander Smirnov, said the crash was not caused by pilot error or mechanical failure.

The Metrojet officials' claims contradict early reports from Egyptian officials that the crew had made a distress call just before the crash. They also may be an effort to fend off concerns over the plane's physical condition – the plane suffered tail damage during a landing in 2001, which may have weakened its structural integrity. Still, the plane passed an inspection in April conducted by the aviation authority in Ireland, where the plane is registered. The Irish Times reports that a team of Irish inspectors will join the investigation in Egypt.

Given Russia's recent intervention in Syria and Egypt's ongoing difficulties with Islamist radicals, terrorism remains a possible cause of the incident. But what little is known so far seems to weigh against this theory.

While the Islamic State's arm in Sinai has claimed responsibility for the plane's destruction, experts say that is unlikely. The Airbus had reached an altitude of 31,000 feet before it fell, a height well out of the range of the sort of anti-aircraft weapons the Sinai jihadists are known to have. While the group does have a variety of anti-aircraft weapons, writes Gulf analyst Theodore Karasik in a commentary for Al Arabiya, their maximum range is 15,000 feet, and all are likely in poor states of repair.

And even if the group did somehow get a hold of a longer range anti-aircraft weapon like the Buk missile system that brought down Malaysian Flight MH17 over Ukraine last year, such a weapon would likely be too sophisticated for IS to wield, claims British military analyst Paul Beaver. He told AP that such a system "requires a bunch of well-trained people, an integrated air-defense network around them. You can't just drive up in a vehicle and fire a missile."

The Guardian writes that a bomb is the most likely theory, assuming there is no technical failure. The Guardian writes that according to an official quoted in a Reuters report, the tail section was burned and separated from the rest of the plane, which would be consistent with an explosive going off. In addition, photos of the wreckage show indications that the tears in the fuselage pushed outward, another sign of a destructive force from within the plane.

Still, the bomb scenario has its own problems. A suicide bomber seems highly unlikely, as the passengers on the plane were almost all Russian – 209 Russians, 4 Ukrainians, and one Belarussian, as well four others whose nationalities have not yet been identified, reports CNN – including many women and children. A terrorist trying to board the plane would likely have stood out and been investigated by airport security. A bomb could still have been planted on the plane or in the luggage, but Sharm el-Sheikh's airport security is as high as most, aviation security experts told the Guardian.

The plane crash may prove particularly damaging to Egypt's tourism industry, which has already been weakened by several years of instability since the 2011 "Arab Spring." RT reports that Egypt is the most popular destination for Russians traveling abroad, with one of every five Russian tourists in the first half of the year visiting it.

But Russian tourism officials say that while they have seen an immediate short-term drop in trips to Egypt, they expect overall rates to remain high. They note that the only recent incident that has led to a sustained drop in Russian visitors was the Tunisian attack in June, and that event involved tourists being specifically targeted.