Northwest Airlines A330 flying from Hong Kong to Tokyo provides frightening parallel to Air France crash

A Northwest Airlines A330 flying from Hong Kong to Tokyo earlier this week, for example, ran into a situation which investigators believe may be a similar to what took place on the flight deck of the Air France jet.

The Northwest crew reported entering a storm in daylight and running into turbulence; in less than a minute their primary and standby airspeed indicators showed the plane had slowed dramatically. Other systems that automatically maintain speed and altitude also disengaged. "The master warning and master caution" indications flashed on the instrument panel, according to one crew member's written description, "and the sound of chirps and clicks (followed) letting us know these things were happening."

Things didn't return to normal for three minutes as the captain flew the aircraft out of the rain, according to information gathered by U.S. safety officials.

The scene inside Air France Flight 447 may have been more ominous from the beginning.

SHOOT: I think we've all been in these big planes through storms and wondered how they weren't pulled to pieces.

clipped from online.wsj.com Based on initial physical evidence and information from automatic maintenance messages sent by the aircraft, these people said, the plane bucked through heavy turbulence created by a thunderstorm without the full protection of its flight-control systems -- safeguards that experts say pilots now often take for granted. Relying on backup instruments, the Air France pilots apparently struggled to restart flight-management computers even as their plane may have begun breaking up from excessive speed, according to theories developed by investigators. An international team of experts is building a scenario in which it believes a cascade of system failures, seemingly beginning with malfunctioning airspeed sensors, rapidly progressed to what appeared to be sweeping computer outages, according to people familiar with the probe. The Airbus A330, en route from Rio de Janeiro to Paris, crashed into the Atlantic Ocean during a storm 26 days ago, killing all 228 aboard.