Friday, May 27, 2011

Air France 447: How Not to Handle a Stall

Air France flight 447 was supposed to take 228 folks from Rio de Janeiro to Paris. Instead, it crashed into the Atlantic. Nobody survived.

That was in June, 2009.

Searchers found wreckage of AF 447 this year: on the floor of the Atlantic, more than a mile under water. They also recovered the flight's data recorders. Pieces of the 'black boxes,' anyway.

A French agency, the BEA, has been looking into why the Airbus fell out of the sky.

Part of the BEA report hit the news today.

Before getting into that, here's what the airline had to say about the accident, in part:

"...Air France praised the three pilots, who 'demonstrated a totally professional attitude and were committed to carrying out their task to the very end,' the airline said in a statement...."
(Wall Street Journal, via FoxNews.com)

That statement may be accurate.

The French BEA's early report shows that the Airbus engines were working normally when the airliner went into a stall: and during the three-plus minutes it took for the airliner to fall into the Atlantic.

The Airbus A330's pitot tubes, a sort of air speed sensor, are known to have trouble with icing. The pilots knew about that, or should have. The pilots also should have known what to do if the things iced up. And what to do if the airliner stalled.

Instead, they did the opposite.

Nose Down During a Stall: Not Up

"Black Box Shows Air France Captain Was Absent When Descent Began"
The Wall Street Journal, via FoxNews.com (May 27, 2011)

"The flight recorders from an Air France plane that crashed nearly two years ago show that the captain only arrived in the cockpit after the plane had begun its fateful 3 1/2-minute descent, officials said Friday.

"The initial findings of the French air accident investigation agency, the BEA, based on a reading of the black boxes recovered from the ocean depths, found that the captain had been resting when the emergency began....

"... 'At the time of the event, the two co-pilots were seated in the cockpit and the captain was resting,' a BEA statement says. The captain returned to the cockpit about 1 1/2 minutes after the autopilot disengaged at 2:10 a.m. and 5 seconds, Coordinated Universal Time....

"...Reacting to wildly fluctuating airspeed indications ... pilots of an Air France jetliner in 2009 continued to pull the nose up sharply - contrary to standard procedure - even as the Airbus A330 plummeted toward the Atlantic Ocean, according to information released Friday by French accident investigators.

"The long-awaited factual report, though it doesn't include any formal conclusions about the cause of the June 2009 crash that killed 228 people, provides details about a prolonged stall that lasted more than three and a half minutes. Throughout the descent, according to the report, 'inputs made by the [pilot flying] were mainly nose-up' and the 'angle of attack,' or the position of the longitudinal axis of the plane in relation to the airflow 'remained above 35 degrees.'

"If an airplane has entered an aerodynamic stall, which means its wings have lost necessary lift to remain airborne, from their earliest training pilots are taught to immediately push the nose down to regain speed, lift and maneuverability.

"The report also paints a somewhat unflattering picture of a seemingly confused cockpit, with the crew making extreme inputs to their flight controls and the engines spooling up to full power and later the thrust levers being pulled back to idle. At one point, according to the report, both pilots sitting in front of the controls tried to put in simultaneous commands....

"...Pilots are trained to avoid such simultaneous commands."

Oh, dear.

Figuring out what went wrong won't bring back any of the 228 people who died on Air France 447. But it might show how to keep another air crew from - apparently - making the same mistakes.

Related posts:
More:

No comments:

Unique, innovative candles

Visit us online:
Spiral Light CandleFind a Retailer
Spiral Light Candle online store

Pinterest: From the Man Behind the Lemming

Top 10 Most-Viewed Posts

Today's News! Some of it, anyway

Actually, some of yesterday's news may be here. Or maybe last week's.
The software and science stuff might still be interesting, though. Or not.
The Lemming thinks it's interesting: Your experience may vary.
("Following" list moved here, after Blogger changed formats)

Who Follows the Lemming?

WebSTAT

Family Blogs - Blog Catalog Blog Directory