Human
performance deficiencies were identified in the investigations of all 11
accidents and human factors overwhelmingly dominated the lists of causes and
contributory factors. The study set out to analyze these deficiencies against
two separate models, the Dupont ‘Dirty Dozen’ and the Pilot Competencies Model,
as described at the outset. All of the accidents had identifiable factors from
both models; indeed some accidents appeared to include deficiencies in
virtually all of the Pilot Competencies together with many of the ‘Dozen’.
The
graph below shows the number of accidents from the original 11, in which each
of the markers from the Pilot Competencies Model was found to be deficient:
It
is perhaps not surprising that the pilots in every accident exhibited deficient
Situational Awareness – had they been more aware of the situation it seems
likely that they would have taken more appropriate action to avoid terrain
proximity. It is disappointing to see that the pilots in all accidents were
also deficient in the application of their procedures but on the other hand
this may be encouraging, in that procedural compliance is possibly indicated as
a significant factor in the mitigation of CFIT risk. Poor communication was
also identified in most (8) of the accidents, supporting a view that CRM (crew resource management) in
general and communication in particular, are vital for the avoidance of CFIT.
The
next graph illustrates the same data for the Dupont ‘Dirty Dozen’ markers:
Once
again Lack of Awareness tops the table, appearing in all of the 11 accidents
and reflecting the deficient Pilot Competency of Situational Awareness above.
There is no Dupont marker that corresponds to the Pilot Competency of
Application of Procedures so we can’t see a correlation but Lack of Communication
again appears in the same 8 accidents. Lack of Teamwork and Lack of
Assertiveness were identified in over half of the accidents and these two
markers are in some ways related. If the Captain in particular is not a ‘team
player’ and fails to respect colleagues and their opinions, the FO may become
isolated and feel unable to intervene, even to save their own life. This risk
is exacerbated by a steep authority gradient in the cockpit. Norms featured as
a marker in almost half (5) of the accidents, when pilots developed and
employed their own processes, either when they found that the promulgated
process was inefficient, ineffective or difficult, or when there was no
applicable process for them to employ.
Stress,
Pressure, Fatigue, Complacency and Distraction each appeared in only 3 or fewer
of the accidents but these conditions are sometimes difficult to identify from
investigation reports. Unless the CVR records specific and attributable voice
characteristics, or the individual mentions that they are affected by a
condition, it may be that the condition goes unnoticed in the investigation.
It
is worthy of note that neither model specifically addresses markers for
Monitoring and/or Cross-checking, although Lack of Awareness and Situational
Awareness respectively could be taken to include those competencies.
Deficiencies in monitoring and cross-checking were apparent in several of the
accidents. It is precisely these functions, functions we know humans perform
quite poorly, that the EGPWS/GPWS/TAWS seeks to augment in CFIT prevention.
Finally,
the graph below combines the two models to show the number of markers
associated with each of the 11 accidents:
Accidents
with a greater number of markers from one model also appear to have a similarly
greater number from the other model – total markers per accident varied from 7
to 14 but the variation between models was never greater than 2. This may
indicate that the two models identify similar human performance deficiencies
but it may also be a reflection of the amount of information available from the
accident reports upon which the study was based. These varied from a few pages
to well over one hundred.
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