Bell Helicopter Co 206L-3, VH-FFI

1. The helicopter departed Rockhampton with insufficient fuel to
   carry out the intended flight, and the pilot was apparently unaware
   of this until some point during the return flight.
2. By the time the helicopter arrived at Marlborough, thick fog
   had formed in the area, preventing a landing at the normal landing
   site.
3. The pilot did not attempt to divert from Marlborough to look
   for a fog-free landing site.
4. While manoeuvring in preparation for an approach to an
   alternative landing site, the engine lost power, possibly due to
   interruption of its fuel supply.
5. Darkness and thick fog, possibly aggravated by the illuminated
   "Nightsun", denied the pilot visual reference with the ground.
6. The investigation was unable to determine why the pilot was
   unable to carry out a safe landing following the loss of engine
   power.

Pilot aspects

The helicopter departed Rockhampton with 500 lb of fuel. This
was insufficient to enable it to fly to Yarandoo and return to
Rockhampton, which was the pilot's original intention. Whether the
pilot miscalculated his fuel requirements or did not consider them
at all, could not be established. It was clear by his decision to
divert to Marlborough that he became aware of his fuel state during
the return flight. His radio transmission to CAPCOM at 0126
reporting his estimate for Rockhampton as 0210 (by which time the
helicopter would have exhausted all its fuel) suggested that he was
unaware of his inadequate fuel state at that time. He would most
probably have become aware of the deficiency when the warning light
indicating 45 minutes of fuel remaining, illuminated shortly
thereafter.

The pilot might have been unaware of the amended area forecasts
including fog, but if he was aware, he may not have considered fog
to be a problem, as he intended to return to Rockhampton. However,
he may have become concerned after deciding to divert to
Marlborough.

A total of 19 minutes elapsed between the helicopter's initial
arrival over Marlborough and the accident. During that time, the
pilot made three attempts to position the helicopter for an
approach to the sports field and one attempt to position for an
approach to the road intersection. There is no evidence to indicate
whether the pilot had considered leaving Marlborough to seek a
fog-free landing site.

Although the pilot did not fly on a full-time basis, he had
successfully undergone a flight review 9 days before the accident.
In the light of the flight review and the short flights since the
check, the pilot's knowledge of all procedures should have been
current. The reason the pilot did not ensure that the helicopter
carried sufficient fuel for the intended flight, could not be
determined.

Any possible effects of medical conditions on the pilot's
performance could not be assessed. Aviation medical opinion was
that given the presence of advanced ischaemic heart disease,
coupled with high levels of stress, the possibility that the pilot
suffered an incapacitating medical event before impact could not be
ruled out. Similarly, the possibility that the pilot may have had
distracting chest pain, even early in the flight, cannot be ruled
out. If the pilot had suffered severe chest pain during the attempt
to land at Marlborough, he might have attempted an immediate
landing and lost control of the aircraft.

If the pilot had been asleep at the time of the CAPCOM call, he
would need to have woken, dressed, proceeded to the CHRS hangar,
prepared for departure and departed, all in a 14 minute period.
Although it cannot be confirmed, the pilot might have been affected
by sleep inertia during the pre-departure period and the early
stage of the flight. If the pilot had been affected by sleep
inertia or had been suffering any chest pain during the
pre-departure period, his ability to prepare for the flight might
have been degraded. However, if sleep inertia had been present, the
pilot would probably have recovered from its effects during the
outbound sector of the flight.

If a lipid analysis of the pilot's blood had been completed in
1997 and its results provided to CASA, it is likely that the pilot
would have been required to undergo a cardiovascular risk
assessment. Due to the inconclusive finding from the autopsy and
the absence of recent medical evidence, the investigation was
unable to determine if the pilot's medical condition contributed to
the accident.

Fuel

Fuel consumption calculations indicate that the helicopter had
125 lb of fuel remaining on arrival overhead Marlborough. Of this,
116 lb of fuel would have been useable. At the endurance
consumption rate of 230 lb/h, 116 lb of fuel would have enabled 30
minutes flying.

Assuming that the pilot flew the helicopter for endurance during
the 19-minute period between arrival over Marlborough at 0144 and
the accident at 0203, the aircraft would have consumed 73 lb of
fuel. This would have left a useable fuel load of 43 lb at the time
of impact, permitting a theoretical 11 minutes of further
flying.

Approximately 22.5 L of fuel (40 lb total, 31 lb useable),
sufficient for 8 minutes flying, was drained from the wreckage and
there was no evidence of fuel spillage or fire. To be useable, all
this fuel would have had to be contained in the rear tank. However,
the fuel was removed from all three tanks and the interconnecting
fuel lines. If fuel in the forward tanks had not transferred to the
rear tank, the remaining flight time would have been less than 8
minutes.

Advice from experienced helicopter pilots was that, in order to
obtain an unobstructed view of a landing area ahead and below, a
pilot seated in the right-side pilot seat could place a helicopter
in an uncoordinated nose-left, right-banked flight attitude. In an
attempt to obtain the best view that he could of his potential
landing site, the pilot might have placed the helicopter into
uncoordinated flight. Alternatively, while manoeuvring the
helicopter, he might have inadvertently placed it into an
uncoordinated turn. With the low fuel level remaining in the rear
tank, an uncoordinated flight condition might have unported the
fuel outlets at the bottom of the rear tank. That could have led to
air being drawn into the fuel line that supplied the engine,
causing the engine to lose power. The pilot would then have been
faced with conducting an approach in autorotation in adverse
conditions.

"Nightsun"

In thick fog and darkness, it is unlikely that the pilot would
have been able to execute a safe approach in autorotation and a
safe landing. If the "Nightsun" had been illuminated during the
autorotation, as one witness suggested, the visibility problems
would have been aggravated due to the light reflected from the fog
droplets leading to virtual "whiteout" conditions.

Engine

The apparent non-illumination of the ENG OUT warning light
following the power loss might have been due to a very short time
between loss of engine power and impact. That time might have been
insufficient for the gas producer RPM to reduce to the 55% +/- 3%
RPM range required to illuminate the warning light.

On 23 July 2000 at 2326 EST, the pilot of a Bell 206L-3
Longranger helicopter was called by the Rockhampton Ambulance
Service Communications (CAPCOM) and requested to transport
Queensland Ambulance Service (QAS) personnel to a patient located
on "Yarandoo", a property approximately 90 NM northwest of
Rockhampton. CAPCOM records revealed that the helicopter departed
Rockhampton at 2340. The flight was conducted under the night
visual flight rules (NVFR).

After arrival at the property, a decision was made to transport
the patient (a child) and his mother to the Rockhampton Hospital.
On board for the return flight to Rockhampton were the pilot in
command, a crewman-paramedic, an intensive-care paramedic, the
child and the child's mother. Throughout the flight, the pilot was
in radio communication with CAPCOM.

At 0114 hours Eastern Standard Time (EST), the pilot reported
departure from Yarandoo and at 0126, passed an estimate for
Rockhampton "10 minutes past the hour". At 0132, the pilot reported
that "because of a fairly high fuel burn rate", he was going to
divert from his present position direct to Marlborough and that he
estimated Marlborough in about 10 minutes. He asked that CAPCOM
arrange road transport to Rockhampton for the patient, his mother
and the intensive-care paramedic. In response, CAPCOM directed a
Marlborough-based ambulance vehicle to deploy to the Marlborough
state school sports field to meet the helicopter.

Fog had formed at Marlborough before the helicopter arrived. At
0141, the pilot called the officer in charge of the
Marlborough-based ambulance vehicle, now deployed to the school
sports field, and asked him to switch on all of the vehicle's
external flashing lights. The ambulance officer replied that the
vehicle's lights were on and that visibility on the ground was
"about the length of a football field".

The helicopter arrived overhead the sports field at 0144. The
pilot could see the vehicle when the helicopter was directly
overhead, but the fog was sufficiently thick to deny the pilot any
slant visibility of ground objects. The pilot then switched the
"Nightsun" searchlight on, and made two further attempts to
initiate an approach to the sports field, without success. At 0154,
the pilot asked the ambulance officer to reposition the ambulance
vehicle to the northern intersection of the Bruce Highway and
Perkins Road, which was illuminated by overhead orange lights. The
pilot said that he could see the cross-pattern of lights and that
he would use the cross as an approach reference. At 0159, the pilot
informed the ambulance officer that he would aim his approach to
the centre of the cross-pattern, and asked the ambulance officer to
check the road going west from the intersection for aerial cables
that could become a hazard during the final approach. A witness
reported that throughout that time, the helicopter's "Nightsun"
searchlight remained illuminated.

At 0201, the ambulance officer informed the pilot that
visibility was about 5 m. The pilot replied, but the reply could
not be understood. At 0203 and again one minute later, the
ambulance officer called the pilot but received no reply. Around
that time, he heard a sound consistent with a ground impact.

At 0206, a Marlborough resident arrived at the intersection and
told the ambulance officer that he believed the helicopter had
crashed. State Emergency Service volunteers, the Queensland Police
Service officer at Marlborough, the ambulance officer and several
residents immediately began to search for the accident site. About
one hour later, two residents searching in fog with 20 m visibility
located the accident site. The helicopter had been destroyed and
all occupants had received fatal injuries.

Wreckage examination

On-site examination of the wreckage revealed that the helicopter
had struck the ground in a steep nose-down attitude while in a left
bank. After striking the ground, the helicopter had rolled forward
and come to rest inverted. The entire forward section of the
fuselage back to the rear cabin bulkhead was destroyed in the
impact sequence.

During the impact sequence the tail boom, with the tail rotor
and tail rotor gearbox still attached, failed and bent downwards
relative to the fuselage. The main rotor gearbox and engine had
separated from the deck attachment and transmission mounting points
but both remained with the wreckage. The main
engine-to-transmission drive-shaft coupling had been pulled out at
the transmission end. There was no evidence of torque twisting or
bending along the shaft. The outer coupling and inner male drive
gears showed little evidence of damage. No significant torque
twisting was evident at the separation points. The type and degree
of damage to the tail rotor blades indicated that their energy
state at impact was low. The twist grip throttle control mounted on
the pilot's collective pitch lever, was badly bent and had been
overwound in the impact sequence, preventing determination of its
pre-impact position. Damage to the engine, the main and tail rotor
assemblies and drive systems was consistent with the engine
delivering little or no power at impact.

The caution/warning panel was removed for laboratory
examination. Four warning lights, ROTOR LOW RPM, TRANS CHIP,
BATTERY RLY and TRANS OIL TEMP were missing from the panel and were
not recovered from the wreckage. Inspection of the filaments of the
recovered warning lights indicated that the FUEL LOW and LITTER
DOOR OPEN lights were illuminated at impact, the GEN FAIL, L/FUEL
PUMP and R/FUEL PUMP lights filament status were inconclusive, and
all other light filaments indicated that they were not illuminated
at impact.

The FUEL LOW light should illuminate when 50 - 75 lb of useable
fuel remains. The ENG OUT warning light should illuminate when the
RPM of the gas producer reduces to 55% +/-3%.

The engine was removed from the wreckage and later set up in an
engine test cell. In the test, the engine started immediately and
accelerated to idle speed normally. After normal heat-soaking, the
engine was accelerated normally to 35% torque. The test run was
carried out using all the accessories that were fitted to the
engine in service before the accident. The test indicated that
there was no technical fault in the engine that would have
prevented it from producing power before impact.

Damage to all other helicopter systems was consistent with
impact damage. The wreckage examination did not reveal any
pre-impact technical fault that could have contributed to the
accident. The maintenance records for the helicopter showed
compliance with all applicable airworthiness directives, and all
required maintenance had been carried out.

Fuel system examination

The entire fuel system, including both main and auxiliary fuel
cells, remained intact. All fuel lines were clear of obstructions
and were intact, apart from one fracture between a bulkhead and the
engine; that fracture was assessed as impact damage. There was no
evidence of fuel spillage or any fuel smell in the wreckage. The
main fuel line to the airframe filter and from the filter to the
engine contained very little fuel. The airframe filter contained a
small quantity of clean fuel in the bottom of the bowl. The filter
was clean with no visible contaminants present.

The main fuel cell was opened for examination and to determine
the quantity of fuel remaining. A total of 22.5 L of fuel was
drained from the three fuel tanks, revealing a maximum useable fuel
load of 17.5 L. There was some green/brown sedimentary growth at
the bottom of the main fuel cell and some small clumps of the
growth on the cell walls. The growth was confined to the rear fuel
tank. There was no evidence of the growth in the fuel lines,
filters or remainder of the fuel system. The "finger filter" on the
fuel control unit was removed for inspection, and found to be free
of any contamination.

A sample of the fuel was taken from the rear tank and sent for
specialist analysis, which confirmed that the fuel conformed to the
density specifications and was free of water and contaminants.

Pilot

The pilot held a Commercial Pilot Licence (Helicopter) and a
Commercial Pilot Licence (Aeroplane) with a Night Visual Flight
Rules Rating. He had 3,928 flying hours of which 3,185 were on
helicopters, including almost 50 hours on the Bell 206L-3
(Longranger). He was a former military pilot whose military flying
experience included 968 hours on Bell 206 (Kiowa) and 2,059 hours
on Bell 47 (Sioux) helicopters. As a military pilot, he had held a
command instrument rating, but his rating was no longer valid.

The pilot was employed as a relief pilot, working tours of
full-time duty with the operator as the need arose. He had
completed previous tours of duty in September and October 1997,
February 1998, April 1998, October 1998, February 1999 and
September 1999, totalling 43 flights. Between tours of duty, he did
not fly. Nine days before the accident, while preparing for his
current tour of duty, he underwent a flight review with the
operator's chief pilot. The flight review included day and night
emergency procedures. On the day following the flight review, he
flew a short NVFR flight, and on the following day, he flew a short
day flight. For the next five days until 0700 on the day of the
accident, he had been off duty.

The pilot was not a permanent resident of Rockhampton, having
taken up temporary residence there during his tours of duty. He had
been living in a house near the operator's hangar since his arrival
in Rockhampton on 14 July. He had completed flights on 15, 16, and
17 July and had then been off duty until 23 July when he assumed
duty at 0700. During that day he remained on standby at the house
of which he was the sole occupant. He was reported to have spent
the day quietly and to have retired to bed early in the
evening.

The pilot assumed the standby duty from the operator's senior
pilot at 0700 on 23 July. The senior pilot reported that he
informed the pilot, amongst other things, that the helicopter was
fully serviceable and that it had 500 lb of fuel on board. The
senior pilot reported that he then offered to brief the pilot on
any aspect of aircraft systems, but the pilot replied that he had
covered the operation of the Global Positioning System and the
"Shadin" electronic fuel management system in discussions with the
chief pilot, and that he was satisfied with his understanding. The
senior pilot also showed the pilot the weather forecast covering
the previous night and warned the pilot to expect fog during his
shift.

The pilot had undergone an annual medical examination on 8 June
2000, and was assessed as medically fit to Class 1 standard, with a
requirement to wear prescription spectacles for vision correction.
However, he had been required to provide a blood lipid analysis for
his 1997 medical renewal. There was no evidence that this analysis
was completed at the required time, but the pilot's designated
aviation medical examiner (DAME) had written a letter to the Civil
Aviation Safety Authority (CASA) dated 19 May 1997, stating that
the pilot's lipids had been analysed in 1995 and were found to be
normal, but provided no figures to substantiate the finding.

Post mortem histology indicated that the pilot had severe
calcific artherosclerosis (otherwise called coronary artery
disease) with a maximum narrowing, although difficult to assess,
estimated to be at least 50%. The post mortem also found a
"localised area of scarring and myofibre hypertrophy, consistent
with ischaemia". The histology indicated coronary vessel disease
(narrowing of the arteries causing a degree of blockage) of long
standing. The changes were indicative of long-term effects
(progressing over many years) of nutrient starvation to focal areas
of the heart muscle, caused by significant narrowing of the
critical coronary vessels responsible for supplying oxygenated
blood to those areas.

The pilot had previously rejected flights that he considered
involved unjustified risk. These decisions had given the operator's
chief pilot confidence in the pilot's judgement, and were key
factors in the operator's decision to employ him.

Weather

The Bureau of Meteorology issued an amended area forecast for
Area 44 at 1852 on 23 July. The amended forecast covered the period
from 230900 Universal Co-ordinated Time (UTC) (231900 EST) to
232300 UTC (240900 EST) and included isolated smoke areas with
scattered fog patches along the coast and ranges from 1400 UTC
(midnight EST) to 2200 UTC (240800 EST). The Bureau issued a second
amended forecast for Area 44 at 2147. That forecast covered the
period from 231130 UTC (232130 EST) to 232300 UTC (240900 EST) and
included isolated smoke areas and isolated fog patches, tending
scattered along the coast and ranges from 1500 UTC (240100 EST) to
2130 UTC (240730 EST). (Area 44 is bounded approximately by the
coastal areas from just south of Rockhampton to just north of
Townsville, inland to Emerald in the south, thence north-west along
a line approximately parallel to the coast and about 250 km
inland.)

By the time the helicopter arrived at Marlborough, extensive
areas of fog had formed. The ambulance officer at Marlborough
estimated the horizontal visibility in the fog from "the length of
a football field" at the school sports ground initially, down to 5
m at the intersection of the Bruce Highway and Perkins Road by the
time of the accident.

The Bureau of Meteorology reported that the temperature profiles
obtained on the day before and on the day after the accident, plus
a pilot report at 2100 UTC (0700 EST), indicated that the top of
some fog patches could have been up to 2,000 ft above mean seal
level (AMSL). The altitude of the top of the fog over Marlborough
at the time of the accident was not determined but observation of
fog patches in the area on the day after the accident indicated
that the top of the fog was about 300 ft above ground level (AGL).
Above the top of the fog, there was little or no cloud.
[Marlborough is 80 m (approximately 260 ft) AMSL.]

Whether the pilot was aware of the amended area forecasts could
not be established.

Fuel management

In addition to the standard fuel management system, the
helicopter had been fitted with a "Shadin" electronic fuel
management system. The system provided information to the pilot,
such as flight time remaining, fuel used and fuel remaining in
addition to fuel flow. According to its manufacturer, the system
had an accuracy of +/- 2% or better. The pilot received information
through a two-window instrument and a flashing warning light
placarded CAUTION - ABOUT TO USE RESERVE FUEL. The warning light
was programmable to illuminate at a given flight-time remaining,
and had been programmed to illuminate when the usable fuel
remaining was sufficient to sustain 45 minutes of flight at the
prevailing fuel flow.

The operator's procedure was to leave the helicopter on standby
with 500 lb of fuel, approximately two-thirds of a full fuel load,
in the tanks. When the operator received a task, the pilot would
calculate the required fuel load and the maximum fuel load the
aircraft could carry given the configuration and payload for the
task.

Section B2 of the company Operations Manual, para. 904, "Fuel
Management" stated that "Fuel consumption planning is to be based
on a minimum of 250 pounds per hour [lb/h] [Long Ranger] and 180
pounds per hour [lb/h] [Jet Ranger] regardless of weight, altitude
and temperature. This figure may be adjusted in flight after
completion of a fuel flow check to confirm actual consumption." For
planning purposes, the operator used a fuel consumption of 250 lb/h
when flying for range below 5,000 ft with the "Nightsun" fitted,
and 230 lb/h when flying for endurance.

The helicopter's last flight before the day of the accident took
place on 22 July; two days previously. After that flight, the
helicopter was refuelled to 500 lb in accordance with the
operator's normal procedure. The operator confirmed that the most
recent fuel delivery to the operator also took place 2 days before
the accident, after the last 500 lb refuelling. The operator's
underground fuel tanks plus six jerrycans kept in the hangar, were
full indicating that no additional fuel above the standby load of
500 lb had been added to the helicopter's tanks before its
departure on the accident task.

The helicopter departed Rockhampton at about 2340 EST and the
pilot reported on final approach for Yarandoo at 0039,
approximately 1 hour after departure. During the flight the
helicopter would have consumed approximately 250 lb of fuel. The
pilot reported departure from Yarandoo bound for Rockhampton at
0114, updated his estimate for Rockhampton at 0126, and reported
his decision to divert to Marlborough at 0132. The helicopter
arrived overhead Marlborough at 0144, after a 30 minute sector and
subsequently calculated to have consumed approximately a further
125 lb of fuel. Thus about 375 lb of fuel would have been consumed
after departure from Rockhampton, leaving approximately 125 lb of
fuel remaining on arrival at Marlborough.

By the time the pilot reported his intention to divert to
Marlborough, the helicopter had flown for 78 minutes, representing
a fuel consumption of about 325 lb. At that time, approximately 175
lb of fuel would have remained, representing 42 minutes of flight
time available. It is likely that the flashing light in the
"Shadin" fuel management system, which was set to illuminate when
45 minutes of fuel remained, had illuminated some minutes earlier,
and that the pilot had used the intervening period to decide to
divert, to determine his new destination, and in consultation with
the paramedics, to determine the further ambulance services
required for the patient.

The flight to Yarandoo and return to Rockhampton would have
required about 120 minutes of flight time, consuming 500 lb of
fuel. The company's operating procedures specified a fuel reserve
of 30 minutes for night operations, so the task required a minimum
fuel load of 625 lb. Configured for the task, the helicopter could
have been loaded with up to 675 lb of fuel to depart Rockhampton at
maximum gross weight.

Queensland Ambulance Service (QAS) tasking

Chapter 31 of the Queensland Ambulance Service Operations Manual
"Aeromedical Operations" detailed all procedures for the operation
of aeromedical services and the persons or agencies responsible for
each step.

Paragraph 3150 of that chapter "Activation Process" detailed
each step between receipt of a request for QAS assistance and
completion of a flight followed by local area transfer of a patient
to a medical facility. The District Communications Centre (DCC) (in
this case CAPCOM) normally received the request and, generally in
consultation with the clinical co-ordinator (a designated medical
officer who determines the medical resource requirements for the
task), would activate the aircraft and crew. On this occasion, a
medical consultation was not obtained. However in retrospect,
medical officers stated that they agreed with the decision to task
the helicopter. Sub-para. (d) of para. 3150 stated:

"The District Communications Centre will then consult the pilot
or service provider to establish the feasibility of the flight,
i.e. weather, aircraft suitability, etc."

The decision to fly is made by the pilot. In discussion, DCC
staff emphasised that they never questioned a pilot's decision not
to fly. Further, it was normal practice in Rockhampton that when
considering an aero-medical operation, DCC staff did not inform a
pilot of the details of a task, thus avoiding any undue pressure on
the pilot to fly. On this occasion, normal procedure was followed
and the pilot accepted the task.

Classification of operations

At the time of the accident, CASA classified aircraft operations
in accordance with the type of flight being conducted. Operators
that carry fare-paying passengers (regular public transport and
charter) are required to meet higher regulatory standards and
receive a higher level of surveillance from CASA than other types
of operators. Emergency Medical Service Operations, and
Search-and-Rescue operations are classed as "aerial work"
operations.

CASA has undertaken a project on Classification of Operations
Policy. Civil Aviation Safety Regulation (CASR) 133, entitled "Air
transport and aerial work operations (rotorcraft)" has been
included within the project. Among other matters, the project is
considering:

1. aircraft certification requirements and crew (including
   supernumery crew) training requirements for aerial work
   operations;
2. introducing performance requirements for helicopters in line
   with similar requirements for aeroplanes;
3. introducing rules specific to certain types of aerial work
   operations;
4. re-introducing minimum fuel requirements; and
5. the issue of "persons directly involved" (including patients
   whose travel has been requested by a medical officer and an escort,
   usually a member of the patient's immediate family) travelling on
   aerial work flights.

CASR 133 is expected to be available from October 2002.

Sleep inertia

Sleep inertia refers to a feeling of disorientation, mental
dullness or sluggishness that occurs after awakening from a period
of sleep. In broad terms, sleep inertia may affect mood, memory,
attention, concentration, cognitive processing, performance
accuracy and reaction time. It is a recognised state of transition
from sleep to wakefulness.

A variety of factors can influence the effect of sleep inertia
on performance. When awakening from sleep normally, the effect of
sleep inertia is believed to last for less than 5 minutes. When
abruptly awoken, the effects have been identified as typically
lasting up to 30 minutes, with some research indicating that
performance can be impaired for over 1 hour.