French Report on Plane Crash Urges New Rules for Pilots

Following a detailed analysis of the circumstances that led to the crash of an Air France jet over the Atlantic Ocean two years ago, French accident investigators on Friday called for a series of significant changes to pilot training procedures aimed at helping flight crews to respond appropriately when they run into trouble at high altitudes.

The recommendations, part of an update on the investigation published by France’s Bureau of Investigations and Analyses, appear to support suggestions by outside experts that fundamental errors by the pilots caused the plane, an Airbus A330-200, to stall and then plummet 38,000 feet into the sea, killing all 228 people aboard.

The report itself stops short of any final conclusions, which are not expected to be made public until early next year. But initial findings highlighted by investigators indicate that the two co-pilots in the cockpit at the time the plane ran into trouble had never been trained to fly the aircraft in manual mode, nor had they been instructed how to promptly recognize and respond to a malfunction of their speed sensors at high altitude — both crucial skills that experts say should have helped them to avert disaster.

The investigators urged European and French air safety regulators to re-examine existing programs for pilot training and skills maintenance, and in particular to “make mandatory the creation of regular specific exercises aimed at manual airplane handling.” Similar training should be required in recognizing the approach to and recovering from high-altitude stalls, the report said.

They also called for more stringent skill requirements before co-pilots are authorized to replace the captain at any time during the flight.

William R. Voss, the president of the Flight Safety Foundation in Alexandria, Va., said the lack of sufficient training for high-altitude upsets was not unique to Air France.

“There is not really time being devoted anymore to these issues,” Mr. Voss said in a telephone interview earlier this week. “It’s a problem across the industry.”

Mr. Voss said long-time safety regulations requiring strict vertical separation of planes in the air have meant that pilots no longer fly manually at altitudes above 24,500 feet. “They never get to feel what the aircraft is like at altitude,” he said

An initial chronology of the flight’s final moments published in May confirmed suspicions that a loss of consistent speed readings, probably a result of icing of the plane’s airspeed sensors, had set off the chain of events that brought down Flight 447 en route from Rio de Janeiro to Paris on June 1, 2009.

Faulty airspeed indicators can mislead pilots into flying faster or slower than the plane can handle.

But investigators found that the loss of valid speed readings lasted for no more than a minute of the plane’s terrifying four-minute descent. Moreover, they found that the aircraft continued to respond to the commands of the pilot at the controls up until the impact with the water.

Those commands, however, were consistently inappropriate for a plane approaching a stall at high altitude: Instead of pointing the nose down in order to regain speed, the pilot at the controls aggressively drove it higher, exacerbating the loss of forward momentum and depriving the plane of essential lift.

According to Friday’s report, the first indication of trouble appeared three hours and 40 minutes into the flight, and 10 minutes after the captain had gone to the crew rest area for some sleep, a normal procedure for a long flight.

As the plane entered a zone of mild turbulence, the autopilot and auto-thrust functions of the plane suddenly disengaged — probably, the investigators said, due to speed sensor icing. But in less than a minute, “the airplane was outside its flight envelope following the manual inputs that were mainly nose-up,” the report said.

As abruptly as the plane climbed — at 7,000 feet per minute, more than twice the rate at take-off — its recorded speed declined, dropping almost instantaneously from 275 knots to 60 knots, the minimum valid velocity recognized by the plane’s computers.

A stall warning sounded twice. The pilots tried several times to call the captain back from his rest area. However, the investigators noted, “neither of the pilots made any reference to the stall warning” — a departure from standard industry procedures. “Neither of the pilots formally identified the stall situation,” they added.