Sunday, January 4, 2015

Airasia crash raises questions about airline safety

The crash of an Airasia Airbus and several other crashes, and the disappearance of a Malaysian Airlines Boeing 777, raise questions about whether pilots in a cocoon-like cockpit are getting enough reliable data to fly safely.

Some pilots have worried that the cockpits have become like the definition of a cocoon, leaving them enveloped or surrounded “in a protective or comforting way.”

The cause of the crash of the Airasia Airbus on Dec. 28 on a flight from Indonesia to Singapore with 162 souls on board is far from being determined. Yet it shares at least two things with the crash of the Air France Airbus en route from Rio de Janeiro to Paris in 2009.

Both jets were flying into storms, and neither sent a distress message. Such disappearances of modern jets were startling.

Years of investigations, and the recovery of key flight data recording systems from Air France 447, showed members of the flight crew were mislead by some data. Essentially they pointed the nose too high, slowing the speed down, and leading to the crash.

At issue here is what pilots call “the angle of attack.” It’s pretty simple. Point the nose down and houses get bigger, pull the stick back and they get smaller. At a certain point a steep climb, which unnamed sources said occurred with Airasia, will cause a stall.

Even at that point, pilots usually can recover. In some cases just handing control back to the auto pilot would save the plane.

The Federal Aviation Administration issued an airworthiness directive on Dec. 10 expressing concern about possible problems in how pilots of Airbus aircraft would handle problems with angle of attack.

Aircraft carrier pilots are experts at being able to do two things at once that would cause many planes to crash: land at relative slow speeds with their noses up. They have to do it to get down on decks of carriers, much shorter than land airfields.

Such precision flying shouldn’t be necessary on a multiengine jet that has already reached 30,000 feet elevation or higher.

This raises the question of whether the flight crews know what they need to know when they encounter storms and turbulence.

The FAA directive said: “The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued Emergency Airworthiness Directive 2014-0266-E, dated December 9, 2014 … (referred to after this as the Mandatory Continuing Airworthiness to correct an unsafe condition on all Model A318, A319, A320, and A321 series airplanes. The MCAI states: An occurrence was reported where an Airbus A321 aeroplane encountered a blockage of two Angle of Attack (AoA) probes during climb, leading to activation of the Alpha Protection (Alpha Prot) while the Mach number increased. The flightcrew managed to regain full control and the flight landed uneventfully.”

Whether the angle-of-attack problem contributed to the Airasia crash is not known, but bears examination for the entire industry.

In the Air France crash, one interpretation of data recorder evidence is that the crew did not understand they were heading to a crash, and therefore did not issue a distress call. A similar event may have occurred with the AirAsia jet.
One old saying aviation was not worry if one of your two engines fails, the other will take you directly to the scene of your crash.

Could better, and possibly more expensive solutions be found? Has cost-cutting, such as not paying for satellite monitoring, made flying less safe than it could be?

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