Plane truth about the AirAsia horror - The Daily Telegraph

THE Indonesian Transport Safety Committee has released its report on the crash of AirAsia A320 last year, in which 162 people died.

It was thought the crew lost control in a severe thunderstorm. I wrote at the time that poor pilot technique was more likely to blame, as a well-trained pilot using the correct pilot technique of just holding the level attitude in the plane’s pitch should be able to penetrate through the updrafts and downdrafts of the cell.

It now appears that weather was not the cause of the crash, but rather inadequate training of the A320 pilots. They screwed up badly.

A minor fault message kept reoccurring on the crew alerting system, called ECAM. The fault in itself did not affect flight safety.

The fourth time the message appeared, the captain decided to deny the ECAM the ability of presenting the message by pulling circuit breakers. This would have disabled certain systems, and the pulling of certain circuit breakers is not a common procedure and should only be performed as part of a checklist procedure to handle abnormal failures.

We now know that the pulling of these circuit breakers caused the plane’s autopilot to disconnect.

It has long been recognised by world aviation authorities such as International Civil Aviation Organisation, as well as flight simulator training organisations like Flight Safety International, that 90 per cent of crashes are caused by pilot error.

FSI’s motto of “safety is a well-trained pilot” says it all.

Airbus and Boeing have designed their modern jet airliners to be operated on autopilot, reducing the chance of human error.

But manufacturers never account for crazy things such as pilots disconnecting the autopilot and deliberately stalling the aircraft while not realising what they are doing.

Manual flight at high altitude requires more concentration on pitch and roll attitude, due to decreased aerodynamic damping, If yaw dampers are not working then the workload increases considerably.

By pulling the circuit breakers, the captain may have caused the loss of the yaw dampers. The ITSC report does state a roll occurred when the autopilots disconnected.

In basic instrument flying training, pilots are taught to select a pitch attitude on the attitude indicator and set the thrust with the throttles to achieve the required performance values. If autopilot disconnects you must maintain the current level pitch attitude and not touch the throttles.

However, it appears that, like the Air France A330 crash out of Rio for Paris over the Atlantic a few years back, the AirAsia co-pilot reacted by pulling back on the sidestick controller causing a massive climb and putting the plane into a full stall.

Pilots these days are not trained to recover from a full stall as the autopilot flight envelope protection will not allow a full stall.

If the pilot puts the aircraft outside the flight envelope then the automatic protection devices are disabled. The aircraft designers never accounted for the strange reactions of poorly trained pilots. Also confusing was the cockpit voice recorder, on which a voice said “pull down”. And yet the first pilot action on stall recovery should be to push the control column forward.

Sadly, the pilots screwed up.

Simulator training is expensive, and the lack of pilots’ manual flying skills is now the major problem facing airlines. This also results from simulator training that mainly concentrates on low level failures such as engine failure on takeoff.

Byron Bailey was a captain for three airlines and a former RAAF fighter pilot. He has 45 years experience and was a senior captain with Emirates for 15 years.


Featured Posts
Recent Posts
Archive
Search By Tags
No tags yet.
Follow Us
  • Facebook Basic Square
  • Twitter Basic Square
  • Google+ Basic Square