Wednesday, April 2, 2014


Pointing fingers


In a NY Times article hededcq Airline Blames Bad Software in San Francisco Crash , Asiana is blaming everyone except its own flight crew.

The NYT article reports that even though Asiana faulted its crew for failing to notice that the airplane was flying far too slowly to stay in the air it claimed that it was not the air crew's fault.

South Korea's Asiana management claims, according to the Times article that

  1. Bad software design led to the unexpected disabling of airspeed protection without adequate warning to the flight crew,
  2. A system to warn the crew of low airspeed did not sound soon enough, and
  3. The approach ordered by air traffic controllers “led to an excessive pilot workload during the final approach.”

Question: Were the Korean airline pilots novices? Did they even have license to fly a Cessna 150 (the modern equivalent of an Aronica Champ or Piper Cub)?

Question: Were the Asiana pilots blind? According to Wikipedia, the weather was fair and the aircraft was cleared for a visual approach - translation: the pilots should have been watching as the aircraft made its final approach rather than depending solely on instrumentation.

Someone recently pointed out that while an airline pilot's log book may show the pilot has thousands of hours at the controls, most of those hours were flown on auto-pilot, cruise control for airplanes.

That's not entirely bad; it should mean the pilots are alert during the most dangerous times of any flight: take off and landing.

In Asiana's case, the pilots apparently were busy with "other" things, depending on automation to do their work for them.

The Times' article states that In the Asiana crash, the crew believed that an auto-throttle would manipulate the engines to keep the plane’s airspeed in the range needed for a safe landing, somewhat like the way the cruise control in a car will adjust the throttle to keep the speed constant. It later became obvious that because of a quirk in two tightly linked systems, the autopilot and the auto-throttle, and because the crew had manually adjusted the throttles at one point, the auto-throttle had gone into sleep mode.

Aside from the fact that it is foolish to depend solely on automation during critical flight periods (take off and landing in particular) there is the suggestion of human err; someone apparently forgot to confirm the auto-throttle was active. Allegedly the Asiana pilots had been trained to be alert for this situation.

To be fair, Boeing (perhaps in General Motors mode?) was warned by the FAA about the way the throttles went into sleep mode but it declined to make a change and agreed to put a warning into the pilot manuals, and, according to the Times, when test pilots from the FAA and the airline tried to fly the approach that air traffic controllers had given the Asiana flight, they had severe difficulties doing so while following other rules, according to papers filed with the board.

Other aircraft regularly successfully land at SFO using the same approach, difficult though it may be, so while the finger Asiana is pointing elsewhere, four fingers are pointing back at Asiana and its pilots.

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