- The pilot departed Margaret Bay later than planned without the certainty that the flight could be completed in the required daylight conditions.
- The pilot continued flight in weather conditions for which he was not currently qualified.
- The pilot continued flight in weather conditions for which the aircraft was not adequately equipped.
- The pilot, after receiving radar navigation assistance, was unable to see the runway lights.
- The pilot possibly experienced spatial disorientation and loss of control while manoeuvring the aircraft in darkness and poor weather without adequate visual cues.
Planning for the flight had ensured compliance with the regulations but provided little or no margin for any delay or poor weather. Despite the narrow margins, there was no evidence of any contingency planning. Although primary responsibility for the safety of the flight rested with the pilot, lack of additional guidance or alternative arrangements, did not provide an opportunity to influence the pilot's subsequent actions. In this instance the pilot considered diverting to Mareeba but, because that did not offer a better alternative, he continued flying toward Cairns rather than landing at Cooktown. It is possible that concerns for the injured passenger and the perishable cargo may have influenced the pilot's judgement and in-flight decision making.
Lack of recent exposure to that type of charter flying may have also affected the judgement and decision-making skills displayed by the pilot. The type of operational decision-making required of a charter pilot was significantly different from the type of decisions required during instructional duties and may have accounted for the pilot's expressed anxiety about undertaking the flight. It could also account for the chief pilot's assessment of the pilot's decision-making ability being inconsistent with that displayed on that occasion.
The pilot's decision to depart Margaret Bay approximately 20 minutes later than the planned latest time of departure was based on his assumption that more favourable winds at a higher altitude might allow an arrival at Cairns before last light. That decision was significant to the development of the accident sequence. The 1520 departure from Margaret Bay meant that the planned flight would arrive at Cairns seven minutes after last light. The GPS navigation unit could have provided the pilot with an estimate for Cairns that would have confirmed that a landing at Cairns before last light was unlikely. The pilot's decision to continue, especially after he received advice that weather conditions at Cairns had deteriorated below VMC, was even more crucial to the outcome. Continued flight in darkness and non-VMC weather conditions ultimately created the circumstances conducive to the accident.
The pilot elected to remain at low-level, below the cloud and in sight of the coast. Although the pilot had previously held an instrument rating, he was not trained to fly an ILS approach. He did not have any recent instrument flight time and probably lacked the confidence to climb the aircraft into cloud and to a safe altitude above terrain. Tracking visually along the coast resulted in a flight path that was not aligned with the extended runway centre line and denied the pilot the opportunity of using approach lighting, in the reduced visibility, for guidance to the runway. Light reflected from the aircraft's landing light beam in the rain and mist may have also prevented the pilot from seeing the runway lights during the unsuccessful approach attempts.
Anxiety produced by the delayed departure, deteriorating weather conditions and darkness, would have combined to increase the pilot's level of stress. The likelihood of fatigue affecting the pilot's cognitive and motor skills due to the mental and physical demands of flying the aircraft, especially in the latter stages of the flight, may have been considerably increased. High stress levels, fatigue and lack of external visual reference most likely contributed to the pilot experiencing spatial disorientation and subsequent loss of control.
The circumstances of the accident were consistent with the pilot experiencing spatial disorientation and subsequent loss of control while manoeuvring the aircraft in darkness and poor weather without adequate visual cues.
History of the flight
The pilot of a Cessna C206 was conducting a charter flight in
accordance with the visual flight rules (VFR) from Margaret Bay to
Cairns with a passenger and a cargo of live seafood. The flight was
reported to have departed Margaret Bay at 1520 EST. At 1719 the
Brisbane Daintree sector controller broadcast, on the area
frequency, the amended Cairns terminal area forecast and the trend
type forecast that indicated visual meteorological conditions (VMC)
did not exist. Six minutes later, when the aircraft was estimated
to have been northwest of Cooktown, the pilot requested the weather
conditions at Mareeba. The controller informed the pilot of the
automatic weather observing system information for Mareeba and said
that he would attempt to obtain a cloud cover report from an
overflying aircraft. The pilot was not informed of that information
nor did he subsequently request it. At 1813 he reported at Cape
Tribulation, 51 NM north of Cairns, and revised his estimate for
Cairns to 1838. That estimate was 10 minutes after last light for
Cairns. Shortly after, a pilot on the airstrip at Wonga Beach,
about 38 NM north of Cairns, sighted the lights of an aircraft
tracking coastal toward Cairns. That observer estimated that the
aircraft was flying at an altitude of 100 ft and in visibility
reduced to less than 1 NM in heavy rain and approaching
darkness.
At 1824, four minutes before last light, the pilot contacted
Cairns approach and reported that the aircraft was 33 NM north of
Cairns. After the pilot confirmed that his operations were normal
the approach controller advised him of the aerodrome terminal
information service (ATIS) weather at Cairns. The controller asked
the pilot if he was able to remain in sight of the coast and if he
was capable of flight in instrument meteorological conditions
(IMC). The pilot advised that he had the coast in sight and that he
was not capable of flight in IMC. The controller subsequently
issued the pilot with a clearance to follow the coast not above
1,000 ft and remain in VMC. Although the pilot had not declared an
emergency, the controller recognised the potential danger and
declared an uncertainty phase.
Radar data from the time the aircraft was identified north of
Cairns showed that the aircraft tracked east of the coast at
altitudes varying between 200 and 600 ft. During that time the
approach controller provided the pilot with cloud and visibility
information reported by pilots conducting instrument approaches to
runway 15 at Cairns. He monitored the progress of the flight and
provided the pilot with distance and groundspeed information. He
also offered the pilot radar headings to establish the aircraft
clear of terrain and position the aircraft for an approach to
runway 15. The approach controller requested that the aerodrome
controller select the approach lighting to maximum illumination.
The pilot, in response to a query by the approach controller,
advised that he had his landing lights on during the approach.
The Cairns meteorological observation at 1830 recorded a
visibility of 2,500 m in rain showers with scattered stratus cloud
at 300 ft and broken cumulus at 1,800 ft. A pilot making an
instrument approach to Cairns ahead of the C206 reported the main
cloud base as 1,100 ft with lower patches of cloud. He reported
seeing the approach lights at 4 NM and the runway lights at 1 NM.
The aerodrome controller estimated that the visibility at the time
the C206 was making its approach was 1,500 m in heavy rain.
When the C206 was almost overhead the airport the pilot reported
that he was unable to see the runway lights, so the controller
instructed him to make a left orbit for a second landing attempt.
The aerodrome controller saw the aircraft descend from 400 ft to
approximately 100 ft during the turn and activated the crash alarm
because he thought an accident was imminent. He selected
omni-directional runway lighting to aid detection. The pilot's
second approach was also unsuccessful and again the aircraft was
seen to lose altitude while turning left. The approach controller
then directed the pilot to take up a northerly heading, away from
obstacles and terrain. He intended to position the aircraft for a
third approach along the extended runway centre line so that the
pilot would be better positioned to use the approach lighting for
guidance to the runway. That flight path took the aircraft over the
water off Machans Beach. At 1851, on the third attempt to approach
and land and while being radar vectored onto a left base leg to
runway 15, the aircraft disappeared from radar 2 NM
north-north-east of Cairns.
Witnesses at Machans Beach reported seeing the lights of an
aircraft flying at low-level offshore. They described seeing the
lights rotate in a manner consistent with the aircraft rolling
steeply to the left and disappearing from view in rain and mist.
One witness reported hearing a faint sound of impact. Airport
rescue and firefighting services had been alerted nearly one minute
before the aircraft disappeared from radar. Despite the inclement
conditions, an air and sea search of the area was conducted by the
Cairns based search and rescue helicopter and rescue craft from the
airport rescue and firefighting service. At 2050, searchers found
the body of the passenger and debris in the water near the reported
accident site. The following day some personal items and debris
from the aircraft were found. Damage to the recovered aircraft
parts suggested that the aircraft had impacted the water heavily
and the accident was not survivable.
Air, sea and coastal searches continued over the next few days,
including the use of airborne electronic detection equipment, but
neither the pilot nor the main aircraft wreckage was found. On 9
November, 3 months after the accident, wreckage was sighted
approximately 4 km offshore. Divers recovered parts from the
underwater wreckage that were later identified as belonging to the
accident aircraft.
Flight planning
The company was contracted to fly cargoes of live seafood,
reported to be valued at up to $18,000 per flight, from Margaret
Bay to Cairns. On the day of the accident, two company aircraft
were scheduled to make the flight. Those flights were normally
flown by instrument rated pilots. Regulations allowed cargo flights
in single engine aircraft to be conducted in accordance with
instrument flight rules (IFR) and at night. That allowed greater
planning flexibility when tide levels dictated later departure
times from Margaret Bay. Although both aircraft were equipped for
flight in accordance with IFR only one had an autopilot. A
serviceable autopilot was a requirement for single-pilot IFR. As
only one instrument rated pilot was available it was decided that
he should fly the auto-pilot equipped aircraft while the accident
pilot flew the C206.
Careful planning was necessary to ensure that the aircraft
piloted by the non-instrument rated pilot could conduct the flight
in accordance with VFR. Flights to Margaret Bay were planned to
arrive and depart during periods when tide levels below 1.8 m
permitted use of the beach as a landing area. On the day of the
accident there were two periods when tide levels were less than 1.8
m, one early to mid morning and the other from 1340 that afternoon.
The earlier period was considered impractical. A first light
departure from Cairns would not have allowed an arrival at Margaret
Bay early enough to complete a normal turnaround on the beach
before the advancing tide. The customer also preferred the later
arrival time which just made possible a normal turnaround and
return flight to Cairns in daylight. The pilot had determined 1500
as the latest time he could safely depart Margaret Bay for an
arrival at Cairns before last light.
Boat crewmembers were sometimes transported to Margaret Bay on
the flights. Regulations governing the carriage of passengers in
single, reciprocating-engine aircraft required the flights to be
conducted in accordance with day VFR. On 3 August a passenger was
to be flown to Margaret Bay. Additionally, the customer requested
that an injured deck hand on the boat be flown to Lockhart River
while the transfer of cargo from the boat to the beach was being
carried out. The deck hand had severed the tip of a finger the
previous day. Although not requiring urgent medical attention he
was anxious to get to hospital where it was reported that
arrangements had been made to have the severed part of his finger
sewn back. Overnight accommodation at Lockhart River had been
arranged for the injured deck hand and a reservation made for him
on the next day's scheduled flight to Cairns. The aircraft operator
advised that the flight was not possible because the additional
flying time to Lockhart River and return would not have ensured
arrival back at Cairns before last light. Instead the operator and
the customer agreed to limit the volume of cargo in the C206 and
fly the passenger direct to Cairns.
Delayed departure from Margaret
Bay
Arrival of the aircraft was signalled to the crew of the fishing
boat by circling overhead. When alerted, the crew commenced packing
the live seafood into tubs in preparation for air transport to
Cairns. Loading and transfer from the boat to the aircraft took
longer than normal. Witnesses reported that the pilot appeared to
be extremely agitated and was visibly distressed about the delay
but he had expressed the belief that more favourable winds at a
higher altitude might enable him to make up the lost time. The
pilot of another VFR aircraft on the beach at that time reported
that he estimated there was inadequate daylight for his return to
Cairns with the existing wind conditions and elected to remain
overnight. He had suggested the same course of action to the
accident pilot but reported that the accident pilot had made up his
mind to return to Cairns that day. Logistically, a landing at
Cooktown would have taken surface transport over eight hours for
the return journey from Cairns. The consequences of that action
would have delayed treatment to the injured passenger and risked
the loss of the perishable cargo.
Pilot
experience
The pilot held a commercial pilot licence and a valid Class 1
medical certificate. He had accumulated 13,157 hours flight
experience during 22 years of active employment in general
aviation. Most of his flying experience was flight instruction and
he held a current Grade 1 Instructor Rating. In 1991 he qualified
for a Command Instrument Rating endorsed for non-directional beacon
(NDB) approaches only. He had not renewed the rating after its
expiry on 30 April 1993. The only recent instrument flight the
pilot recorded were practice NDB approaches on a synthetic
procedure trainer in preparation for revalidation of his lapsed
instrument rating. In the 90 days prior to the accident he had
logged 6.6 hours of night flying that included a navigation
training flight and a check flight with the Chief Pilot.
During the 12 months preceding the accident the pilot had
recorded 515 hours of which 35 hours were charter flying. Nearly
all of that charter flying consisted of short local scenic and
aerial work flights. Although the pilot had not flown to Margaret
Bay for some time, he was familiar with the York Peninsula area.
The 72-hour history of the pilot did not reveal any circumstances
that would have affected his ability to perform his duties. The
family of the pilot reported that he was unusually anxious about
undertaking the flight and had expressed concern about the
available time frame for the flight. The chief pilot, who was
responsible for rostering pilots, described the pilot as reliable
and possessing sound judgement. He described the pilot's decision
to continue the flight in darkness and poor weather as
uncharacteristic.
Aircraft and
equipment
It was not possible to determine if there was any aircraft
defect that may have contributed to the accident sequence.
Examination of the small amount of wreckage that was recovered
indicated that the aircraft engine was developing some power at the
time of impact. Inspection of the aircraft's maintenance
documentation showed that the required maintenance had been
certified as completed. Pilots who flew the aircraft before the
accident flight reported that it had been serviceable. The aircraft
was certified for flight in accordance with the instrument flight
rules (IFR). An entry on the duplicate copy of the maintenance
release stated that there was no autopilot fitted and that for IFR
operation in accordance with Civil Aviation Order (CAO) 20.18
subsection 4.1B (ie, Charter or Airwork), two instrument rated
pilots were required. The duplicate copy of the maintenance release
also noted that no Emergency Locator Transmitter (ELT) was
installed. The aircraft was equipped with a VHF omni-directional
radio range (VOR) receiver, incorporating glideslope information
that enabled instrument landing system (ILS) approaches to be flown
and automatic direction finding (ADF) radio navigation aids. The
pilot had borrowed a portable hand-held Global Positioning System
(GPS) satellite navigation unit for the flight and had mounted it
on top of the instrument panel. The unit also displayed tracking
and groundspeed information.
Weather
The forecast obtained by the pilot that morning indicated that
VMC could be expected along the planned route but with visibility
reduced to 2,000 m in isolated areas of drizzle, showers and smoke.
The Cairns terminal area forecast (TAF) issued at 0825 forecast VMC
with showers of rain but no further deterioration until 2000; well
after the planned arrival at Cairns. At 1328 the Cairns TAF was
amended to include an intermittent (INTER) deterioration in
conditions below VMC from 1600. An INTER is used to indicate
changes expected to occur frequently for periods of less than 30
minutes duration, with conditions fluctuating almost constantly,
between the times specified in the forecast. The amended Cairns TAF
also included a temporary (TEMPO) deterioration in conditions from
2000. TEMPO is used to indicate changes in prevailing conditions
expected to last for a period of less than one hour in each
instance. A further amendment to the Cairns TAF was issued at 1531
that forecast a visibility reduced to 9,000 m in showers and
patches of low cloud with a base of 800 ft. A TEMPO period from
1800 forecast visibility reduced to 2,000 m in showers with patches
of low cloud at 300 ft. This was the forecast broadcast by the
controller at 1719, while the aircraft was estimated to be
north-west of Cooktown.
Recorded rainfall data indicated that rainfall intensity at
Cairns airport for that day was greatest between 1800 and 1900.
VFR
considerations
The Aeronautical Information Publication stated that day VFR
flights must not depart from an aerodrome unless the Estimated Time
of Arrival (ETA) for the destination or alternate is at least 10
minutes before last light, after allowing for any required holding.
Calculations based on aircraft performance and forecast winds gave
a planned time interval of 3 hours 15 minutes. That meant that a
departure from Margaret Bay at 1520 would result in an ETA for
Cairns of 1835, seven minutes after last light. The amended Cairns
TAF with the INTER requirement, broadcast by the controller at
1719, would have necessitated an arrival at Cairns no later than
1748 in order to meet the requirements for VFR flight. Pilots of
VFR aircraft faced with similar circumstances were taught, as part
of their training, to make an in-flight diversion to another
destination while weather and daylight permitted. Weather
conditions at Cooktown that afternoon were reported to be VMC.
Operational
control
Operational control was defined as the exercise of authority
over the initiation, continuation, termination or diversion of a
flight, in the interest of the safety of an aircraft.
Prior to January 1992 the then Civil Aviation Authority through
its specialist air traffic services personnel provided a
comprehensive operational control service. Pilots of VFR flights
proceeding more than 50 NM were required to submit flight plan
information that was checked by controllers to ensure compliance
with regulations and operational requirements. Operations
controllers with access to current weather and NOTAM information
monitored all flights to ensure that pilots were aware of
significant changes to weather and other operational factors that
may affect the safety of the flight. That information was
transmitted through the aeronautical communications network to a
pilot and, when considered necessary, an appropriate response
sought. In extreme cases, pilots could be directed to land or be
diverted to ensure the safety of the flight.
Following a review of that service, changes to Australian
regulations were made to more closely align with international
regulations. Those changes resulted in the withdrawal of the
operational control service and greater responsibility for the safe
conduct of a flight to the pilot in command. In effect that meant
that operational control was exercised by a pilot complying with
regulations, standard operating procedures as published in company
Operations Manuals and by displaying sound airmanship.
The Civil Aviation Safety Authority (CASA), in its program of
regulatory reform, intends to require air transport (incorporating
what is currently termed charter) operators to establish and
maintain a method of supervision of operations. If accepted, the
changes would require operators to state in their Operations Manual
the means by which operational control is to be exercised. It is
envisioned that such regulation would cover at least a description
of responsibilities concerning the initiation, continuation,
termination or diversion of each flight and include specific
information to pilots on suitable alternate aerodromes and the
means of updating weather and NOTAM information.
Decision-making
In the manual "Aeronautical Decision Making for Commercial
Pilots" developed for the United States Federal Aviation
Administration (FAA), the point is made that charter pilots often
have to balance commercial considerations against safety and
compliance with regulations. In doing so they can be subjected to
pressures from management, clients and passengers more attuned to
non-safety related issues such as economy and expediency. Those
people may assume that the pilot will resist these pressures if
there is any "real" danger and respond appropriately to avoid
disaster. Conversely, pilots can be persuaded, even to the
detriment of safety, by the knowledge that a decision contrary to
the wishes of the customer or management may incur economic
penalties that could adversely affect commercial viability and
hence their employment. Pilots who regularly fly in such
environments become used to recognising those conflicting demands
and practicing their decision-making skills.
The importance of good pilot decision-making skills was
recognised by the Civil Aviation Safety Authority. In 1996
decision-making as a topic was included in the Human Performance
and Limitations section of the Day VFR Syllabus (Aeroplanes) of the
Aeronautical Knowledge requirements for pilots. The requirements
included a knowledge of the basic concepts of decision making
including the influence of employer pressure, the desire to get the
task done, workload management, work overload and currency. That
knowledge requirement was not made retrospective. Transport Canada
introduced a similar requirement for commercial pilots engaged in
multi-crew operations to complete a "once only" pilot
decision-making course. Following an accident in 1998 involving a
high-performance single-engine turbine aircraft, the Canadian
Transportation Safety Board recommended that the requirement be
extended to all pilots engaged in commercial operations.
Risk
management
Identifying hazards and developing contingency plans to avoid or
mitigate their effect is a risk management strategy used by
safety-conscious individuals or organisations to reduce risk. The
transport of perishable cargo from a remote beach landing site
presented additional hazards to that of normal charter operations.
The company had addressed the hazards associated with landing and
taking off from beaches by determining tide heights that permitted
adequate runway width and by additional beach take-off and landing
training for pilots. Flights made under the IFR were not as likely
to be delayed or diverted and reduced the risk of losing valuable
cargoes because of the perishable nature of the live seafood.
However, use of VFR aircraft and pilots increased the possibility
of weather or daylight affecting an assured arrival.
The VFR pilot of the other aircraft engaged in the transport of
live seafood from Margaret Bay to Cairns had identified risks
associated with his operation and taken precautions to avoid them.
He had fitted a marine high frequency channel to his aircraft's
radio to permit direct communication with the fishing boat crew.
That enabled him to advise them of his arrival so that they could
prepare for the transfer of cargo and avoid delay. He also
forewarned the crew of his latest time of departure of 1445 and his
alternative arrangements for an overnight stay should the deadline
not be met. Importantly, when the boat crew failed to meet the
deadline he implemented his contingency plan and flew to a nearby
island where he remained overnight, returning the next day as
arranged, to collect the cargo and fly it to Cairns. That was the
course of action he had suggested to the pilot of the C206 on the
beach at Margaret Bay.
The Civil Aviation Safety Authority, in a discussion paper
issued in May 2000, proposed changes for certification of
commercial air transport operators (incorporating charter) that
included an obligation for those operators to introduce an accident
prevention and flight safety program incorporating risk management
processes and hazard identification.