At least three Britons were on board flight SU593, which disappeared from radar screens four hours into the 10-hour flight from Moscow to Hong Kong and crashed in a wooded valley near the town of Mezhdurechensk, 40 miles east of Novokuznetsk in Siberia. Rescuers reached the site on skis and found no sign of life. The Airbus was capable of carrying 185 passengers.
The bomb theory was initially discounted by Russian authorities but last night it seemed more likely that terrorism was to blame. The Deputy Minister for Emergencies, Yuri Vorobyev, was quoted by the Interfax agency as saying that he could not rule out terrorism as a possible cause.
Suspicions arose because fewer than one in ten air crashes occur when planes are at their cruising altitude of about 30,000 feet. In this case, air traffic control lost contact with the three crew in the cockpit nearly 20 minutes before the Airbus crashed. Yuri Korinevsky, an official with the Russian Transport Ministry, described the lengthy communications break as 'suspicious'.
David Learmount, safety editor of Flight International, who collates statistics on air accidents around the world, said there were two similarities with the crash of a Pan Am Boeing 747 in December 1988 which killed 270 people. 'As with the Lockerbie crash, there was no communication with the pilots between cruising height and the crash, and no emergency call was put out.'
He said control of the engines on modern planes was always through computers which, along with the communication system, could be disabled by quite a small bomb - as happened in the Lockerbie disaster.
Russian investigators, who were still searching for the flight recorder last night, said it would take 10 days to ascertain the cause. Local lumberjacks say they saw the plane coming down out of control but not on fire.
This is the second major crash involving Aeroflot this year - at least 120 people died when a Tupolev 154 went down in January. But while the Russian airline's standards of maintenance have been questioned in the past, this aircraft was maintained by a French company.
Aeroflot's international flights have a much better safety record than its internal ones and this was the first accident on an international flight since a Tupolev-134 crashed near East Berlin in 1986.
The Foreign Office was unable to confirm whether there were more Britons among the 63 passengers and 12 crew; there were also a number of Chinese and citizens of Canada, the United States, India and Australia.Reuse content