Beech Aircraft Corp 76, VH-TTB

Company safety action

The company has undertaken to provide a fuel tank dipstick for
the aircraft.

CASA safety action

Prior to this incident, the Civil Aviation Safety Authority
(CASA) had released an NPRM (Notice of Proposed Rule Making),
which, in part, deals with precautions before flight and fuel
management, as part of the review of the Civil Aviation
Regulations. CASA's intent is to introduce regulations that are
simple and unambiguous.

The NPRM document contained the following proposed
regulations:

'91.180 Precautions before flight

1. The pilot in command of an aircraft must, before flight,
inspect the aircraft and review all factors relevant to the safety
of the flight that can reasonably be assessed before departure.

2. When reviewing factors likely to affect the safety of the
flight, the pilot in command of an aircraft must take such action
as is reasonable to ensure that, before take-off, all of the
following requirements are met:

k) sufficient fuel is on board the aircraft for it to land at
the end of the flight with the required fuel reserves still on
board;

l) the quantity of fuel in the aircraft's fuel tank or tanks has
been checked by visual inspection or by 2 different methods.'

The pilot did not establish the actual fuel quantity on board
the aircraft prior to departure.
The aircraft fuel tanks contained insufficient fuel for the
planned flight.
The right fuel quantity gauge transmitter unit was
inoperative.

The checks conducted by the pilot prior to the flight were
inadequate to the extent that the pilot significantly
over-estimated the quantity of fuel available for the flight.

The right engine failed due to insufficient fuel in the right
tank while the aircraft was in a climb attitude. However, the pilot
was apparently confused by the indications of the failure, as
evidenced by his attempts to feather the propeller, but then
continued with the propeller windmilling, on the assumption that
some power was still available. This was despite readily available
indications that the engine had failed. The pilot's apparent
confusion was probably due to insufficient recurrent training in
emergency procedures relevant to the aircraft type.

The pilot apparently over-relied on the tachometer and manifold
pressure gauge indications, but lacked an understanding of those
indications. Had the pilot recognised that the engine was not
producing power, he may have persisted with his attempts and
feathered the propeller. This would have increased the aircraft's
performance by significantly reducing drag and should have
permitted a greater degree of safety for the subsequent return to
Essendon.

When the pilot manipulated the throttle lever of the failed
engine as part of his engine failure confirmation checks, he should
have realised that the engine had lost all power. The yawing of the
aircraft as the pilot moved the pitch lever towards the feather
position, due to reduced propeller drag, should also have provided
a strong indication that the engine had failed.

With marginal aircraft performance, the pilot passed two
suitable airfields and rather than divert to Moorabbin, continued
to Essendon. This may suggest that fatigue, and possibly a desire
to minimise inconvenience to the passengers and the operator
adversely affected the pilot's judgement.

The pilot had planned to conduct a charter flight, with three
passengers, from Essendon to Latrobe Valley, Vic. in a twin engine
Beech Duchess aircraft. The pilot reported that he arrived at the
Essendon airport about 90 minutes prior to the scheduled departure,
carried out the daily inspection on the aircraft and submitted an
instrument flight rules flight notification. He checked the
aircraft maintenance release and the company fuel log that included
the aircraft's last flight four days earlier. The pilot reported
that he checked the two fuel quantity gauge readings which
indicated a half-full tank and a slightly less than half full tank.
He then visually checked the contents of the tanks relative to the
'30 US gallon' metal tabs that are visible through the filler
opening. He estimated that the fuel tanks contained a total of
about 200 litres, but did not confirm this, as a fuel tank dipstick
was not provided for that aircraft. The pilot's flight plan
indicated that 128 litres of fuel, including reserves, would be
required for the flight.

During the climb to the planned altitude of 7,000 ft, the right
engine's power reduced. The pilot concluded that, from the engine
tachometer reading of 1,500 revolutions per minute, and the
manifold pressure indications, the right engine had partially
failed. He carried out engine failure confirmation checks, but as
the propeller pitch lever was very stiff, was unable to place it in
the feather position. The pilot later reported that, during
manipulation of the pitch lever, the aircraft had yawed
significantly. Therefore, he decided to reset the right engine
controls to a cruise setting because partial power was preferable
to no power.

The aircraft was unable to maintain altitude so the pilot
decided to return to Essendon. He requested an air traffic
clearance from the Melbourne Approach air traffic controller (ATC)
when the aircraft was about 50 NM east of Essendon. After receiving
a clearance, and as he turned onto a westerly heading, the aircraft
descended into cloud. At the pilot's request, ATC provided headings
for the pilot to track further to the south to avoid the higher
terrain on the direct track to Essendon. Lowest safe altitude
(LSALT) is a published or pilot calculated minimum altitude that
ensures terrain clearance during flight in instrument flight
conditions. Flight below an LSALT altitude is only permissible
during visual meteorological conditions or while conducting a
published instrument approach. When the aircraft descended below
the LSALT, ATC advised that a diversion to the closer Moorabbin
airport, which was to the south east of Essendon and to the south
of the aircraft, was available. That option would have allowed the
aircraft to track over lower terrain and would have minimised the
track distance over the Melbourne suburbs. However, the pilot
decided to return to Essendon, where the operator's maintenance
facilities were located and the passengers could be transferred to
another company aircraft. After descending through the next LSALT
step while in cloud, the aircraft descended into visual conditions
about 21 NM east of Essendon at about 2,500 ft. The aircraft
continued to descend until it stabilised in almost level flight at
about 1,500 ft. The pilot then tracked direct to Essendon and
carried out a visual approach and landing.

The pilot had bypassed two other suitable airfields, Lilydale
and Coldstream, approximately 10-15 NM to the right of his track.
The Civil Aviation Safety Authority (CASA) Civil Aviation Orders
(CAO) 20.6 permitted the pilot of an aircraft with a failed engine
to fly past a suitable aerodrome if another suitable aerodrome was
available nearby and the pilot assessed that the aircraft could be
flown safely to that aerodrome.

Company engineering inspection of the aircraft found that the
right fuel tank, that was supplying the right engine when it lost
power, contained no fuel. The right fuel quantity gauge transmitter
unit was corroded and seized in a position that resulted in the
gauge always indicating half-full. It was possible to feather the
right propeller, although the pitch control was stiff.

The control cable and the fuel tank sender unit were
subsequently replaced. The pilot commented that he had conducted a
feather check as part of the pre-takeoff checks and although the
right pitch lever was stiff to operate, he was satisfied that the
propeller feathering mechanism was operating satisfactorily. The
pilot later commented that the engine had failed due to fuel
starvation and that he had not recognised the symptoms of a piston
engine failure. He reported that he did not notice the reduced fuel
pressure to the right engine until after the aircraft descended
into visual conditions.

The aircraft's pilots operating handbook cautioned pilots
against attempting to determine the inoperative engine by reference
to the tachometers or the manifold pressure gauges and stated that
those instruments often indicated near normal readings after an
in-flight engine failure.

The pilot had recently resumed employment with the operator. He
began his career with the operator and had flown as a first officer
on F-27 turboprop aircraft for four years. He then obtained
employment with a regional airline for two years as a first officer
on turboprop aircraft, and had just completed line training as
first officer on a jet aircraft when that airline suspended
operations.

The day before the incident, the pilot had completed a 12-hour
tour of duty, including 8.1 hours of flight time completing a
co-pilot endorsement on a business jet. The two days prior to that
had been spent on ground duties. He had 6-8 hours rest overnight at
home and had risen early on the day of the occurrence. The pilot
reported that he was tired on the day of the occurrence and that he
had felt similarly for some time. He had been on duty for 16
consecutive days or a total of 159.4 hours duty time, primarily in
a capacity unrelated to his employment as a pilot. Those additional
duties were reflected in the pilot's recorded duty times.

The pilot had logged about 3,600 hours total flight time,
including 600 hours in command on piston-engine aircraft. Those
command hours consisted of about 200 hours twin-engine, of which 25
were in Duchess aircraft. All his other flying had been in
turboprop and jet aircraft. During the three months preceding the
incident, the pilot had flown approximately 70 hours, but had only
flown the Duchess for three hours during that time.

The pilot's work/rest history for the four weeks prior to the
incident was examined using a computerised fatigue algorithm
developed by the Centre for Sleep Research, University of South
Australia. The results indicated that the pilot was probably
experiencing moderate levels of fatigue in the week leading up to,
and on the day of the incident.