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Old 29th Oct 2013, 03:16
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Sarcs
 
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Three cheers to the VA crew job well done!

Given this incident has now led to two dedicated threads (Operational non-compliance involving a Boeing 777,VH-VPH, near Melbourne Airport)and numerous references in many others, I think full credit should be given to the crew for properly reporting this incident to the ATSB.

Here is the bare bones summary of the VA crew initial report (as listed in the ATSB weekly summary):
During the approach, the autopilot commanded a high rate of descent. The crew disconnected the autopilot and manually continued the approach. The investigation is continuing.

And here is where the ATSB investigation currently is at: AO-2013-130

The healthy debate that has so far occurred in both threads dealing with this incident just goes to show the value of learning from such occurrences when they are properly reported and in this case investigated.

Although the crew in this incident appear to have appropriately recovered the situation (automated dirty dive that could have had dire consequences otherwise ) there have been several recent incidents/accidents where the outcome, to say the least, has been less desirable.

sheppey mentions one of them:
Perhaps VA management and also ATSB could learn something useful about automation dependency by attending the USA conference on the Asiana 777 accident. See below.
NTSB Announces Investigative Hearing on Asiana Flight 214
Note: I would also suggest that there are a lot more stakeholders (other than VA management & the ATSB) that would benefit from attending the NTSB conference.

sheppey’s comment also highlights one of the chestnut safety issues that is troubling the worldwide aviation community and is being proactively tackled by the likes of the NTSB and the Flight Safety Foundation.

A bit of google research on the subject of Asiana Flight 214 and automation dependency brings up some interesting articles/references but surprisingly one of the most informative comes from a group of investigative journalists called the NBC Bay Area Investigative Unit: AnAutomation Trap for Pilots?

There is also another side effect of automation dependency and that is sudden and unexpected a/p disconnection (which amongst other things has got experts rethinking cockpit design):
Redesign for Sudden Autopilot Disconnection Needed, Say Flight Safety Experts

Flight safety experts studying recent high-profile plane crashes found sudden autopilot disconnection to be a design flaw that creates unnecessary emergencies by surprising pilots during critical, high-workload episodes.

"The sudden disengagement of autopilot is analogous to a pilot suddenly throwing up his or her hands and blurting to the copilot, 'Your Plane!'" says Eric E. Geiselman, lead author of a recently published two-article Ergonomics in Design series, "Flight Deck Automation: Invaluable Collaborator or Insidious Enabler" (July issue) and "A Call for Context-Aware Logic to Improve Safety" (October issue).

Eric E. Geiselman, along with coauthors Christopher M. Johnson, David R. Buck, and Timothy Patrick, have combined expertise as pilots, crew resource management instructors, and human factors researchers. They studied the 2009 Colgan Air crash in Buffalo, New York, and the 2009 Air France crash off the coast of Brazil with a focus on how humans and machines can best communicate on the flight deck.

The authors recommend that autopilot systems transfer controls following the same protocols crew members use -- with acknowledgment by the receiving pilot that he or she has assumed control. FAA regulations require a visual and auditory warning to occur following autopilot shutoff, but Geiselman et al. emphasize that such warning should occur before -- not after -- autopilot is disengaged.

Geiselman et al. report on many other design-level safety issues in these articles and offer prototypes featuring solutions that can be affordably implemented with available technology. They believe better design of automation technology on planes can prevent future accidents and that more pilot training shouldn't be the only solution pursued by the industry.
The other safety issue chestnut, that the VA 777 incident appears to be invoking debate on, is the parameters of a stabilised approach and when to initiate a go around. In light of Asiana Flight 214,amongst other similar incidents/accidents in recent years, the Flight Safety Foundation took the initiative to investigate what is regarded as the leading causal factor for runway excursions i.e. unstable approaches. The following is a FSF article on the subject which should help to liven up the debate: Failure to Mitigate

And a quote from that article to (hopefully) kick off some robust comments :
Example of a Go-Around Experience

1. At a point immediately above SAH, the pilot’s “gut,” or what we refer to as affective awareness, subtly signals him or her to confirm that the aircraft’s flight characteristics and profile are normal. In a near-instantaneous and seamless fashion, this might be followed by

2. A visual check, or what we refer to as a check to provide functional awareness, which would be made where the pilot’s expert knowledge and ability to understand the instruments plays a key role in confirming whether the cue from their gut was, in fact, correct. Simultaneously, there is …

3. An immediate and confirmatory statement from the pilot’s network of past experiences, or critical awareness, occurs, in which professional experience confirms the presence of a “normal” flight profile. Seconds later, however, imagine that in continuing its descent below SAH, the aircraft encounters significant turbulence with headwinds shifting to tailwinds and downdrafts altering VREF (reference landing speed) by +21 kt, accompanied by a vertical descent now greater than 1,100 fpm. Instantly, …

4. The pilot’s anticipatory awareness, the ability to see these threats, registers in harmony with the reactivated gut, expert instrument knowledge and experience — all awarenesses that are now signaling a non-normal event — and there arises an immediate need for a signal from...

5. Task-empirical awareness, the pilot’s expert knowledge of the safe operational envelope limits of the aircraft. Imagine further that this expert knowledge confirms that although the aircraft is now unstable, it still remains within the safe operational envelope. However, before concluding that parameters are now safe or unsafe, manageable or unmanageable, this developing event requires immediate input from another awareness competency …

6. Compensatory awareness, or the ability to understand how to compensate correctly for non-normal events, occurs by referencing through functional awareness whether the aircraft and the instruments will direct the flight state back to a normal condition if acted upon. Whether the answer, not yet fully formed but informed by critical awareness, is likely to be “yes,” “no” or uncertain, imagine that the pilot is also simultaneously receiving …

7. Through relational awareness — the pilots’ knowledge of how they use their relationships to protect safety — input from a crewmember that re-enlivens a memory trace of a prior verbal signal, based on a conversation and agreement earlier in the approach initiated by the pilot monitoring, that a go-around might be necessary should the aircraft become unstable at or below SAH, which …

8. Informs and motivates the pilot to engage hierarchical awareness, or the individual’s expert knowledge of operational procedures under specific operational conditions, so as to confirm their ability to safely fly a go-around if necessary. Finally, with the pilot-in-command and other crew rapidly coming to a common assessment of, and agreement about, the risks inherent in continuing with the unstable situation that faces them, in comparison with the inherent risks of any go-around maneuver, and...

9. Confident that their company would support a decision to initiate a go-around, and in an expression of their environmental awareness concerning the wider organizational reward structures surrounding support for safety, the pilot flying puts all of these elements of awareness together to judge that the risks confronting the flight crew are not fully manageable, and so decides to call for a go-around.
Some more articles from FSF on this safety issue: The Rare Go-Around & Why Do We Forgo the Go-Around?

Fill your boots...and IMO three cheers to the VA crew!

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