An investigator’s conclusion that the Air France jet that crashed into the Atlantic last month did not break up in the air makes it more likely that many of the 228 people on board were alive when it hit the water, say experts.

Two separate trails of bodies and debris more than 50 miles apart suggested a high-altitude break-up of the Rio-to-Paris flight on June 1, in which passengers would have died instantly. The first official report on flight AF447’s crash ruled that out, however, suggesting some passengers may have survived until impact.

Debris indicated the Airbus A330 hit the water intact, on its belly and in the direction of the flight, said Alain Bouillard of the French air accident investigation unit.

None of the bodies discovered was in a life jacket and it is thought many passengers were not wearing seatbelts. If the cabin became depressurised, they may have lost consciousness as the plane began a descent from 35,000ft — oxygen masks are not thought to have been deployed.

Without data from the “black box” flight recorders, it may never be known what went wrong. A submarine search for the recorders’ location signals will continue until Friday, after which their batteries are sure to be dead.

Some suspicion rests on the plane’s exterior air speed sensors (pitot tubes), which have been known to get blocked and confuse the onboard computer — in recent years causing cockpit emergencies. But investigators said potentially faulty pitot tubes were “a factor but not the cause” of the crash.

Some 640 pieces of wreckage have been found and 51 bodies, including the pilot and one of five Britons killed in the crash.

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