Chapter 8
Human factors
8.1
The term 'human factors' refers to the study of 'people's performance in
their work and non-work environments.'[1]
The term denotes both positive and negative aspects of human performance. In
the aviation safety context, the term is often used in reference to factors
influencing human error.
8.2
The committee heard about the central importance of human factors to an
investigation in order to understand why an accident occurred. However, the
committee heard that such information was lacking in the ATSB report.[2]
In this chapter the committee will cover some of these areas which witnesses
believe should have been included in the ATSB report.
Importance of human factors
8.3
The ATSB acknowledges the importance of human factors:
The purpose of applying Human Factors knowledge to such
investigations is to not only understand what happened in a given accident, but
more importantly, why it happened.[3]
8.4
The ATSB's own information notes:
Human Factors are a critical part of the safety investigation
process and are at the heart of most aircraft accidents.[4]
8.5
The ATSB website points out the agencies expertise in and contribution
to the field of human factors at both the individual and organisational level
which is acknowledged as world class.[5]
8.6
The ATSB Chief Commissioner has also personally emphasised the importance
of human factors:
The field of human factors is—and always will be—an essential
part of the ATSB’s investigation process.[6]
8.7
The importance of human factors principles was also stressed to the committee:
As we said in our submission to the committee, we have a
comprehensive methodology for doing this [assessing whether existing
arrangements for managing safety risk are adequate]. That methodology takes as
its starting point, its base, the principles of human factors that were
initially enunciated by Professor Reason and have been built on by a range of
others. So, rather than seeing human factors as a separate issue in our
investigations, we have integrated them into our overall processes.[7]
8.8
Mr Bryan Aherne, an independent aviation accident investigator and
safety and risk adviser to the aviation industry, pointed out the international
requirements for an investigation which include human factors:
The collection of Human Factors information is an integral
part of the investigation. Thus, the Human Factors information should be
integrated into the appropriate areas of the factual part of the report, rather
than being placed under a separate heading. Human Factors information should be
presented in a language that is consistent with the presentation of the other
factual information.[8]
Lack of human factors information in the ATSB report
8.9
The Australian and International Pilots Association (AIPA) submitted
that from its perspective the ATSB report:
...lacks any significant analysis of why the pilot in command
attempted the task in the manner he did. The presentation of 'facts' alone is
unhelpful, since the investigators must have some insight into what, at least
in the raw form, appear to be an apparently uninformed approach to conducting a
potentially risky flight.[9]
Factors influencing decision making
8.10
Witnesses raised a number of examples where in their opinion a greater
analysis of human factors was warranted. Unless otherwise indicated, the
committee's analysis of specific VH-NGA flight details relies on material drawn
from the ATSB investigation report.
The effect of incorrect weather
information provided and weather not provided
8.11
After entering Fijian airspace at 0716,[10]
at 0756 Capt. James requested the weather for Norfolk Island. Fijian ATC provided
an observation (METAR) that was an hour-and-a-half old (METAR are issued every
30 minutes) (0630) which Capt. James queried by asking for confirmation of the
time of issue. It also contained the wrong cloud height which was read out as 6000
instead of 600 ft.[11]
This was not corrected by Fijian ATC (Air Traffic Control) at the time. It was also
not corrected in the ATSB final report until the day after it was published.[12]
There is therefore no discussion in the ATSB report of the possible effect of
this incorrect cloud height on the decisions made subsequently by Capt. James.
8.12
Very shortly after the METAR with the incorrect cloud height was read
out, the controller advised the availability of the latest weather observation
for Norfolk Island. The SPECI (0800) was provided by Fijian ATC at 0802 and was
only read out because Capt. James queried the time of the 0630 weather report.[13]
It reported an observed visibility of greater than 10 km and overcast cloud at
1100 ft above the aerodrome reference point (ARP). The ATSB noted that these
conditions were less than the alternate minima but above the landing minima.
The report then goes on to say that Capt. James acknowledged the information.[14]
The report does not discuss this matter further and the reader is left to
conclude for themselves whether or not the information is received and
understood by Capt. James.
8.13
To clarify, the two reports read out to Capt. James were issued an hour
and a half apart but were provided less than a minute apart.
8.14
At 0803 an amended forecast (TAF) was issued by the Bureau of
Meteorology (BoM) which had broken cloud at 1000 ft above the ARP.[15]
It indicated conditions below the alternate minima but above the landing minima
at the ETA. This also was not passed on to the crew.[16]
The ATSB notes that this information was not required to be passed on[17]
and this issue is discussed further in Chapter 9. An 0830 SPECI not requested
showed a marked deterioration but this also was not passed on.[18]
8.15
The ATSB report mentions that the pilot did not enquire about the
availability of an updated forecast.[19]
Mr Davies pointed out that they were not required to make this enquiry and they
had no compelling reason to do so. At this time they had a valid TAF for
Norfolk Island with forecast conditions above the alternate minima and were not
aware of the significance of the SPECI that had been passed on.[20]
8.16
The mental picture the crew would have developed as a result is
discussed later in this chapter. Discussion around the reasons for the crew not
being aware of the information contained in the SPECI is below.
Changing weather reports
8.17
As an example, witnesses highlighted that the crew did not have an
awareness or appreciation of the 0800 SPECI[21]
so its influence on their in-flight decision making was nugatory. It was argued
that the reasons for this lack of awareness or appreciation are not adequately
examined in the ATSB report.[22]
8.18
The contention by the ATSB appears to be that the pilot-in-charge was
alert to the wrong timing of the requested (0630) observation but then after
hearing about the deteriorating conditions in Norfolk shortly afterwards via
the SPECI, took no action. The contrasting view would be that because the pilot
queried the issue time of the 0630 METAR but did not query the SPECI and took
no further action, that this shows the transmission was never heard or
assimilated in its entirety. The ATSB report indicates that the crew reported
that they were either not aware of or did not recognise the significance of the
SPECI, and if they had, would have planned in case an en route diversion
was necessary.[23]
However, the report does not discuss possible scenarios regarding why the crew
were not aware of the relevant information in the SPECI.
High frequency radio issues
8.19
The committee noted some conjecture around whether the pilot-in-command
heard the SPECI transmitted by high frequency (HF) radio. Further detail on
this is provided below.
8.20
The reliability issues with HF were recognized by the ATSB at a
committee hearing but not in any detail in its report. Any possible influence
is dismissed by the ATSB report in noting that no difficulties were identified
by the flight crew with their radio communications during the flight.[24]
However, when discussing the provision of weather information at a hearing Mr
Dolan acknowledged that the reliability of HF ‘can vary, depending on the time
of the day, among other things’.[25]
Mr Dolan also admitted that despite the pilot's acknowledgement of the
information, the receipt could have been distorted by HF.[26]
Mr Dolan added that although the transmission to and from the aircraft that was
recorded by Auckland does not appear to show any distortion he recognised that
it may have been different in the cockpit.[27]
8.21
At the 21 November 2012 hearing when asked about the number of times the
crew asked for information to be repeated, Mr Dolan's response was that it
occurred once to Fijian ATC.[28]
In answering this question on notice the ATSB maintained that the pilot only
used 'say again' once at 0630 to query the time associated with the 0630 METAR.[29]
Overall the ATSB indicated that the flight crew used the term 'say again' a
total of three times during the conduct of the flight.[30]
8.22
Mr Aherne pointed out that according to the partial transcript provided
to Capt. James the words 'say again' appear seven times—five times between
Auckland ATC and the aircraft in the period 0600–0637 and twice between the
aircraft and Fijian ATC and the aircraft in the period 0716–0801.[31]
8.23
With the transcripts available, which were the same as those referenced
by Mr Aherne, the committee concurs with Mr Aherne that the term 'say again'
was used at least seven times. As these transcripts were obtained from the ATSB
the committee concludes that, in this regard, the ATSB report is factually
incorrect.
Expectations/state of mind
8.24
There was no analysis in the ATSB report on what effect the error of the
cloud height had on the crew's understanding and mental picture of the weather[32]and
subsequent decision making. The information in the 630 METAR and the incorrect cloud
base at 6000 instead of 600 ft may have contributed to a mindset or expectation
that with an hour and a half until the ETA and cloud at 6000 ft nothing could
happen in that time that would close the airfield.
8.25
The mental picture from the initial forecast would have been reinforced
by the incorrect cloud height information from the METAR that conditions were
good, in fact even better than the original forecast. It would have had the
effect of confirming the pre-flight forecast that weather was unlikely to be a
problem. Even if the SPECI had been heard clearly and in full, the pilot may already
had a mental model of a 6000 foot cloud base. It would be understandable human
nature to underestimate or disregard information that does not fit with the
model of good weather already developed in the pilot's mind. He may have heard
the information but not understood it clearly because he already had a mental
picture that conditions were good and so he acknowledged the information
without acknowledging the changing weather conditions. He also may have had a
picture developed in his mind that replicated his experience of the previous
evening when he flew into Norfolk Island on the outbound leg, where the poor
weather forecast on departure from Sydney did not match the actual fine conditions
on arrival.
8.26
There is no discussion of these possibilities in the ATSB report. Other
weather information that may have ensured the crew comprehended the
deteriorating conditions earlier was not passed on and this is discussed below.
Fatigue
8.27
Another possibility that may have contributed to the information not
being heard or assimilated correctly could have been fatigue. The ATSB report
has no detailed discussion of fatigue. It concluded that 'there was
insufficient evidence available to determine the level of fatigue, or the
extent to which it may have contributed to him [the pilot] not comprehending
the significance of the 0800 SPECI'.[33]
As the timing of the 0630 METAR was questioned by Capt. James, it appears that
fatigue alone cannot explain the lack of action. This however should not have
precluded the ATSB from analysing the issue of fatigue but adds weight to the
need to analyse other factors. A more detailed discussion of the issues around
fatigue is below.
8.28
Mr Mick Quinn pointed out there was no Selective Calling[34]
so the flight crew had to monitor the frequency for the duration of the trip,
listening to white noise, which adds to fatigue.[35]
Committee view
8.29
The committee acknowledges the uncertainty over whether the relevant
weather information in the SPECI was received by the flight crew in total
and/or assimilated. It too finds it strange that there is no discussion or
analysis around the possible reasons for this, particularly given the ATSB
re-enactment video of the incident showed that Capt. James was surprised when
he heard the word SPECI and was adamant he had not heard it.[36]
8.30
The committee is aware of the issues around HF radio communications and
that its reliability varies considerably depending on the frequency used and
range. The committee recognises that there are a range of known technical
issues associated with HF radio which can make it a poor form of communication
particularly over water at some range.[37]
While the ATSB report noted that no communication issues were identified by the
crew, Mr Dolan acknowledged that the transmissions may have been heard
differently in the cockpit and the committee finds it odd that there is no
discussion of this in the report.
8.31
Despite acknowledgement of the information by the pilot, the actions of
the crew and the reactions in the re-enactment video show that for whatever
reason the information was not heard and assimilated correctly or in its
entirety. It may have been heard in a way that the crew was unaware it was
incomplete. Despite the care taken by the pilot to check the time of the 0630
METAR, the ATSB appear to conclude that less than a minute later the pilot heard
of significantly deteriorating weather conditions and took no action. The
committee questions the likelihood of such a scenario.
8.32
While the committee acknowledges that using the term 'say again' is
usual to clarify information received, there is currently no requirement to
repeat critical information[38]
and perhaps there should be and this report could have provided the opportunity
for that discussion.
8.33
In the committee's view it would also be important to include some
analysis of the possible effect of the incorrect weather information on
decision making. The incorrect cloud height was corrected by the ATSB the day
after the report was published but no discussion of the effect on decision
making was included.
8.34
The committee considers there is no certainty around the transmission
and receipt of the information in the SPECI.
Recommendation 16
8.35
The committee recommends that, where relevant, the ATSB include thorough
human factors analysis and discussion in future investigation reports. Where
human factors are not considered relevant, the ATSB should include a statement explaining
why.
Fatigue
8.36
As mentioned above, the possible contribution of fatigue was not
examined in any depth by the ATSB. The ATSB report acknowledged that the flight
crew had been awake for over 12 hours before being called on duty at 0900 for
the departure from Sydney on the previous day. They had been awake for over
22 hours when they landed in Samoa.[39]
The report stated:
After having breakfast they had about 8 hours opportunity at
a hotel for rest prior to returning to the airport. The captain initially
reported to the ATSB that he slept for most of this period and was well rested,
but later reported to the Civil Aviation Authority (CASA) that he had only
about 4 hours sleep but did not feel fatigued. The first officer advised of
having 5 to 6 hours of sleep and feeling well rested.[40]
8.37
The ATSB noted that based on this information 'it is likely that the
flight crew were experiencing a significant level of fatigue on the flight to
Samoa, and if the captain only had 4 hours sleep then it is likely he was
experiencing fatigue on the return flight at a level likely to have had at
least some effect on performance.' However, the ATSB concluded:
...there was insufficient evidence available to determine the
level of fatigue...[41]
8.38
While the ATSB concluded it could not determine the level of fatigue, Mr
Quinn pointed out that the crew were still alive and could have been re‑interviewed,
the crew could have provided a 72 hour history for fatigue analysis and the
ATSB could have commissioned an external review by fatigue specialists.[42]
8.39
Mr McCormick commented that only a pilot knows whether or not they are
fatigued.[43]
Other witnesses highlighted that the individual concerned is usually the worst
placed to accurately assess their own level of fatigue which is why best
practice involves various tools and systems to support individual and
organisational decision making.[44]
8.40
The committee is aware that 'managing fatigue and associated risks are
the dual responsibility of employers and employees'.[45]
CASA's guidance to industry on this issue states that an employer's responsibilities
include:
- develop work schedules that prevent high levels of fatigue from
developing during a work shift.
- develop work schedules that allow for adequate rest and recovery
periods during between shifts (that allows for an anchor sleep period of seven
to eight hours).
- ensure safe work practices, such as limiting overtime to sensible
levels.
-
implement appropriate and safe shift duration.
- continuously assess, control, and monitor fatigue-related
hazards.
- develop policies, procedures, and practices to manage risks
related to fatigue. For example, where napping is allowed, there should be
clear instructions on how to deal with sleep inertia.
- provide information on workplace hazards, such as fatigue.[46]
8.41
Mr Dolan was questioned about the view that only a pilot can decide if
they are fatigued. He clarified that in the context of a Fatigue Risk
Management System (FRMS) there is the ultimate decision of a pilot that needs
to be made with appropriate knowledge and training as to whether their fatigue
levels make them fit for the flight. The committee reminded the ATSB of the
deficiencies with the operators' FRMS and training and asked if it had
effectively analysed the issue. Mr Dolan argued that the ATSB analysis was
adequate for the purposes of its investigation.[47]
8.42
The committee notes that CASA sought independent advice from the UK
Civil Aviation Authority (CAA) which indicated that the scheduled flight would
never have received UK CAA approval as it would have exceeded its
bio-mathematical model (SAFE[48])
fatigue limits. Accordingly to the UK CAA analysis, the crew exceeded the
fatigue limit on arrival in Apia from Norfolk Island and would most certainly
have exceeded the fatigue limit during the return flight. The UK CAA went
further and criticised the culture of Pel-Air based on the extent to which
crews were kept on standby.[49]
CASA did not pass this analysis onto the ATSB.
8.43
The ATSB confirmed that it did not obtain any independent analysis of
fatigue levels and did not think it necessary to do so. It also questioned
aspects of the UK CAA analysis.[50]
8.44
The ATSB's reticence to analyse whether fatigue contributed to the
accident was criticised by Mr Aherne who noted:
...the reader cannot ignore that ATSB's reluctance to develop
any analytical arguments regarding fatigue and its potential contribution to
the accident sequence despite its statement regarding fatigue in the final
report, that...it was likely that on the return flight the pilot in command was
experiencing fatigue.[51]
8.45
The ATSB[52]
and CASA[53]
both played down the usefulness of fatigue modelling. However, the committee
heard this is disingenuous as fatigue models such as SAFE are the most accurate
tool available and are very accurate in predicting fatigue and retrospectively
analysing fatigue. The committee was told that these fatigue models are not
perfect but are a significant step forward when compared with the arbitrary
limitations established in CAO 48.0.[54]
8.46
Relying on the crew's recollection of fatigue[55]
should be treated with caution as any admission by flight crew of flying while
knowingly fatigued invites a charge of negligence and second, humans are a poor
judge of their fatigue levels.[56]
8.47
Mr Aherne also pointed out the obvious learning opportunity which should
be a standalone finding regardless of whether it contributed to the accident or
not:
It is inadvisable for an operator to place the burden of
responsibility on the flight crew to determine their level of fatigue prior to
commencing a duty and make a prediction as to their likely level of fatigue
many hours hence.[57]
Committee view
8.48
It seems a matter of common sense that if the crew had been awake for
22 hours by the time they landed in Samoa the issue of fatigue and
management of it would be analysed by the ATSB. The statement that there was
insufficient evidence available to determine the precise level of fatigue,
despite acknowledging that the PIC was likely to be experiencing fatigue,
should not have prevented the ATSB from analysing this issue.
8.49
The ATSB's own documentation prepared for the investigation noted that 'there
is a discrepancy between self-reports of fatigue and actual fatigue levels,
with people generally underestimating their level of fatigue'.[58]
The committee believes that the ATSB report is a lost opportunity to have a detailed
discussion on the management of fatigue, particularly given the deficiencies in
this area identified in the CASA Special Audit (see Chapter 5).
8.50
The committee notes the ability for CASA to outsource or confirm fatigue
analysis by going to the UK CAA. It notes the ATSB concerns with the analysis
but that this option would have been available to the ATSB as well, or
alternatively CASA could have shared the information it received from its UK
counterpart. This aside, the CASA FRMS report (Chapter 5) combined with the
evidence received by the committee provide a robust case that the management of
fatigue was inadequate.
8.51
The Committee notes the early expectation of ATSB officers that human
factors, including fatigue, would form part of the investigation. Worryingly,
when the ATSB again looked at fatigue, prompted by the DIP process, the ATSB
documentation indicated that the officers wanted to review the operator's FRMS,
re-interview the crew and take further action[59]
but that ATSB management concluded that the investigation could not deviate at
this point in the investigation and that the investigation team have to work
with what they already have.[60]
8.52
The committee considers that there are questions to be answered around why
there was no discussion or analysis of degraded performance due to fatigue when
decisions were a) being made in Apia regarding fuel load or b) being made en
route in response to weather forecasts. With the latter, the committee is
concerned with the inexplicable interaction with Fiji where crucial information
appears to not have been heard or assimilated.
8.53
The point of the ATSB report should be to cause other pilots and
operators to consider how fatigue may affect their safety. It is an example of
why the approach taken by the ATSB is flawed and does not optimise safety
outcomes from the investigation which should be about why this accident
occurred.
Retrieval of the CVR/FDR
8.54
As noted in Chapter 3 of the committee's report, which among other
matters highlights the importance of information contained in flight data
recorders, the ATSB chose not to retrieve the aircraft after the accident.
8.55
Mr Aherne pointed out that the retrieval of the cockpit voice recorder
would have assisted to fill in some gaps in terms of the human factors such as:
the relationship between the pilot and the co-pilot; their reaction to the
ATC's requests or instructions; their lines of thinking; and the conversations they
were having on the flight deck.[61]
Committee view
8.56
The committee agrees that flight recorders can reveal facts which are surely
key assets to an investigator as they provide concrete data and information,
helping them avoid theories and assumptions.[62]
The industry has expended significant capital to equip aircraft with FDR and
CVR creating the expectation that having made the investment that the ATSB will
recover the records so that any lessons will be evidence based.
Other issues around survivability
aspects
8.57
The committee heard that there are numerous aspects relating to the
ditching that many pilots would find useful. The committee heard that the adequacy
and location of emergency equipment should have been more thoroughly examined
after the accident.[63]
8.58
Mr Aherne pointed out that without the pilot-in-command's waterproof
torch this could easily have been a six-person fatality. The role of failed
safety equipment on the lifejackets (lights and inflation chambers and
whistles) and the incorrect position of the life raft (positioned untethered in
the aisle before ditching) are important issues that in the committee's view
should have received more attention in the ATSB report.[64]
Lifejackets
8.59
Reports from the crew and passengers were that the lifejackets did not
function appropriately. This was not reflected in the ATSB report. The issues
were described by the pilot-in-charge:
Only three of us managed to fit life jackets before exiting
the aircraft—the doctor, David; the nurse, Karen; and the patient’s husband,
Gary. Zoe and I were far too busy while flying the aircraft to undo our
seatbelts and fit the life jackets. The patient, Bernie, was not fitted with a
life jacket as per CareFlight’s procedures for someone on a stretcher. During
the evacuation, there was also no chance to grab additional jackets to make up
the shortfall...
The jackets themselves had issues. The lights were very dim
and did not remain illuminated for very long. I understand they are supposed to
be seen from some distance and remain on for eight hours or so. The groin strap
of David's life jacket was too long or not able to be tightened sufficiently
and at times you needed to hold his jacket down with one hand so he could
breathe without difficulty. David’s ears were also covered up, making him
effectively deaf while we were in the water. The lanyards on the signalling
whistles were not long enough or were knotted. This meant you could not use
your own whistle and instead someone else was required to. The manual inflation
and deflation tubes were a similar size and shape to the whistles and a few
times they were accidently activated when they were mistaken for a whistle in
the darkness and pulled towards the face of the person wearing the jacket,
causing the jacket to deflate.[65]
8.60
Mr Aherne pointed out:
The lifejacket lights did not work for eight hours as they
are required to. Miss Casey's [the flight nurse] life jacket only inflated in
the left chamber. She held the patient in her right arm for an hour and a half.
She has permanent disabling injuries of her hand. If her other chamber had
inflated she would have been able to cradle the patient, who did not have a
lifejacket. How that information is omitted is bizarre.[66]
8.61
The survivors reported that most of the lifejacket lights had stopped
working by the time they were recovered by the rescue vessel.[67]
8.62
The ATSB report noted that the aircraft was equipped with lifejackets
for all on board as well as two life rafts.[68]
8.63
The ATSB said that the reports about the performance of the lifesaving
equipment varied from the survivors and some of the performance issues might
have been due to the dark night or difficulty exiting the aircraft.[69]
8.64
Mr Aherne questioned why after three years the ATSB have been unable to
establish the facts around the lifejackets as they were available and should
have been examined.[70]
He submitted that the ATSB should have been able to determine whether the
damage occurred during the accident sequence. He pointed out that in the
absence of an examination there is a possibility that there is a serviceability
issue with the lifejackets which could potentially affect a large section of
the industry.[71]
8.65
Curiously, ATSB documentation showed that the ATSB assumed that CASA has
sufficient information in relation to battery life to take some action in
relation to the lifejackets. Internal ATSB documents noted that it is up to
CASA to investigate lifejacket deficiencies, as it has sufficient information
to act and so a recommendation was not made.[72]
However, it does not appear that any industry advice or caution regarding the
failures has been issued.
8.66
Mr Dolan admitted that:
As I understand it having reviewed the various materials, we
did examine the question of life jackets—on reflection, perhaps not at the
level of detail we should. With the life rafts, I do not recall that there was
any examination in detail. In terms of the survivability aspect of the report,
it is certainly not comprehensive.[73]
8.67
The ATSB committed to re-examine the lifejacket safety issues:
We will re-examine that part of the report. In light of the
evidence that has now been brought to our attention, and that was not brought
to our attention during the investigation or in the factual review of the
reports...[74]
Life rafts
8.68
The ATSB report noted:
The life rafts were reported removed from their normal stowed
position and placed in the aircraft’s central aisle ready for deployment after
the ditching.[75]
8.69
In relation to the life raft the pilot-in-command noted:
The Pel-Air ditching preparation procedures called for the
25-kilo life raft to be placed next to the exit on the floor and left there.
Unsurprisingly, during the impact, the life raft tumbled forward and was lost
in the darkness. I do not know why someone at Pel-Air or CASA did not question
the likelihood of a life raft remaining in place during the violent
deceleration of an aircraft ditching and did not suggest an alternative
procedure.[76]
8.70
He then suggested:
There needs to be a procedure where the life raft was secured
in a fashion which would ensure the raft remained in place during the impact—but
allowing it to be recovered without difficulty and put through the exit and
deployed on the surface. I understand that is not an easy undertaking, but the
processes in place at the time was inadequate.[77]
Committee view
8.71
Again the committee saw in ATSB documentation the expectation from investigation
officers that cabin safety, including location of life rafts and the design of
lifejackets, would be included.
8.72
After a three-year investigation it seems incredible, given that all on
board survived, that some issues with the lifejackets only came to light during
the course of this inquiry.
8.73
The committee finds it difficult to comprehend that no caution was
issued for the lifejackets, and that the situation and position of the life
raft was not discussed as a lesson for the aviation industry. The committee
notes the lack of action in relation to lifejackets and battery life appears
again to be linked to a decision not to issue a recommendation to CASA. This is
yet another disturbing example of an opportunity lost.
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