A roundup from readers around the world.
1) Korean pilots doth protest. According to AVweb, the union representing Asiana pilots has filed a protest against the NTSB because of "NTSB's press conferences which only give prominence to the possibility of a pilot error."
Hmmm. The NTSB has pointed out that under ideal weather conditions, with no indication of mechanical failure of any kind, the plane's approach path toward the runway was never "stabilized" in altitude or air speed. Also, that about a second before impact, the cockpit voice recorder showed that the crew attempted (too late) a "go-around" to climb away and set up for another approach. Most accidents occur because of (a) a mechanical failure that redundant safety systems somehow can't cope with, (b) extreme weather of some sort, or (c) an error in judgment, execution, or decision-making, for whatever reason, by the plane's crew. The NTSB has said that so far there is no sign of causes (a) or (b).
2) Airframe improvements. On a brighter-side aspect of the crash, reader TH notes a dramatic yet under-appreciated implication of the event:
I haven't seen it remarked upon elsewhere, but one of the most incredible aspects of the accident, to me, is the fact that the plane remained virtually intact except for the tail section that took the initial impact. The crash video shows the enormous forces the airframe withstood -- the fuselage, wings still attached, whips around almost 360 degrees horizontally and perhaps 45 vertically -- and yet neither the fuselage nor the wings seem to suffer much damage, let alone shred apart. I can't help but note the extraordinary physical strength, and of course extraordinary engineering and manufacturing, involved.Leaving aside all the advances in control, reliability, sensors, etc., surely that basic physical toughness represents a giant leap forward in passenger safety compared to 50 or even 25 years ago. Similar, perhaps, to the way automobiles have gotten safer over that period?
Yes. And a similar change has been notable even in the small-aircraft world. The kind of airplane that I fly, whose design and origin I described in Free Flight and that is now the best-selling small plane of its type in the world, has a fiberglass cockpit and airframe that have proven amazingly robust. The best known safety feature of these Cirrus SR-22 airplanes is the parachute for the entire airplane that can be deployed to avert a crash. But even when the plane has been banged up by trees or towers while descending under the parachute, the tough fiberglass cabin structure has stayed intact.
3) The role of fatigue. Dr. Daniel Johnson of western Wisconsin, who has long experience in both aviation and in medicine (and has been an FAA-designated senior medical examiner since the mid-1980s), writes about another factor:
As a pilot, and as a physician interested in mistakes of perception and circadian biology, I think nothing could be more obvious than, whatever else happened mechanically or procedurally, this Asiana 777 crash was likely related to jet lag, sleep deprivation, and its consequences on judgment, perception, vigilance, and reaction time. The flying-pilot's limited hours in the 777 is a red herring, as he has 12,000 hours of experience.
1: All the pilots in this aircraft were finishing a long eastbound flight from Korea.
2: We don't know that they slept well when off duty during the flight.
3: We don't know that their duty schedule, sleep schedule, and light-dark schedule were ideal during the prior week or two.
4: We don' know that they had managed their circadian rhythms wisely.
We have clear evidence of degraded judgment and reactions:
1: A decision to perform a hand-flown visual approach to the runway...
2: A very low visual approach to the runway implies inattention, which implies degraded awareness.
It is much harder to judge altitude when over water than when over land, as any pilot of seaplanes knows. Nevertheless, there would have been adequate visual clues, particularly the perspective view of the runway and the PAPIs. [JF note: these PAPIs are the red and white lights to help you judge if you are too high, too low, or just right on the descent.] I have much experience with low approaches; there is no doubt about one's glide angle unless perception is clouded.
3: Slow reactions and obvious misperception, with degraded awareness, imply fatigue.
A: failing to correct for the low approach angle
B: failing to notice the slow airspeed (137 kt normal, about 105 knots actual) - Normally the pilot continually checks the airspeed. Failing to glance repeatedly at this indicates degraded attention, vigilance, and perception. There was not a cockpit call for more speed until 7 seconds before hitting the seawall. [JF note: if it turns out that the actual approach speed was 32 knots lower than the normal range, that is an enormous difference. Normally you try to maintain approach speed within 1 or 2 knots of the target speed.]
C: Failing to respond instantly to the stick-shaker (which began 4 seconds before impact; the pilot should have initiated instantly application of more power - jet engines don't respond instantly, but the correction should typically occur in about a half-second, even with a surprised pilot. Power was applied 2.5 seconds later, just 1.5 seconds before hitting the seawall.
D: failing to apply power before the nose was raised. This is a failure of basic pilot skills. Power first, then attitude.
E: Raising the nose as a reaction to the stick-shaker. This is wrong! The stick-shaker means that a stall is beginning; raising the nose guarantees a stall (and caused the tail to strike the ground). This a very common error, even among professional pilots, a Delta / Air Force Reserve pilot instructor has informed me. [JF note: Go back to all the discussion of the Colgan/Buffalo and Air France/mid-Atlantic crashes for more on this theme.]
Ironically, an airplane's effective stall speed and rate of descent are both significantly lower - the induced drag is perhaps halved - when the airplane is within a wingspan of the ground/water ("ground effect") If this pilot had not panicked and pulled the nose up, this airplane could have been landed - awkwardly but without breaking the tail off on the seawall - without trying to speed up or to climb - simply by continuing to fly in ground effect to the runway. [JF note: Whether continuing in "ground effect" could indeed have saved the flight is one of the things the NTSB will presumably figure out.]
So we see a collection of events that likely occurred due to degraded attention, vigilance, judgment, and reaction time. This severe impairment occurs with fatigue. This is most commonly due, in professional pilots, to jet lag and sleep deprivation...As you know better than I, fatigue is not, as is often portrayed, "not getting enough sleep." Fatigue is a complex symptom of diverse causes. Inadequate sleep duration is only one.
Dr. Johnson also sent a link to this very interesting medical-journal article about the surprising manifestations of fatigue, and the ways people and cannot try to overcome circadian rhythms.
4) Maybe it's about Confucian culture. A Westerner who has long held a senior position as a manager in China sends this view. For US readers: this Hiddink he refers to is a soccer coach whose international reputation would be comparable in American terms to Phil Jackson's or Vince Lombardi's:
Hiddink's magic transformed South Korea co-hosting the 2002 World Cup by somehow improving its record from five first round knock-outs in previous appearances to fourth place. How?He very quickly changes the attitude of a country, its team and players. When Guus went to Korea there was shyness - the younger players would not talk to the older ones,Hiddink realized while watching former games of the Korean team, that very often, young players were well positioned to score, but passed on to an older player, even though that blew most chances.He made the older players step forward in the circle of players and bow (!!) and ask the younger and more junior players to score themselves, that it was ok not to pass on to a more experienced and senior member of the squad.Hiddink had to break the pattern of Korean seniority, to get them to the semis (where they lost against Germany). He was fully aware of stories circulating at that time, that a Korean Airliner went down in Guam, as the younger pilot did not dare to correct the elder and more senior pilot
5) But maybe it's not. A reader sends in this reference:
About the "cockpit culture" discussion: I'm more interested in individuals, and it seems that a captain, for good or ill, can have an enormous impact on the rest of the crew's performance during operation of the aircraft. As shown in this story.There is a lot of commentary on the web about this particular captain's habits and reputation. This article touches on that, as well as the inadvisability of "slam-dunk" approaches.
As you'll see, the story is about a crash in Minnesota nearly 20 years ago in which blame was fixed firmly on the captain for disregarding his junior officers' warnings that the plane was headed for trouble. With, again, no sign that the captain had ever heard of Confucius. That's it for now, thanks to these and other readers.
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