Fuel starvation

FACTUAL INFORMATION

History of the flight

Before departing Moorabbin for Cooma on 17 September 1994, the aircraft's main fuel tanks were filled with aviation gasoline (AVGAS) and 50 litres were added to each auxiliary tank, providing at least 515 litres total fuel on board. The auxiliary fuel tank gauges had indicated near empty before the addition of the fuel. The pilot assessed from the gauge readings that the tanks had contained a small quantity prior to refuelling and that the total fuel load was 550 litres.

The flight time to Cooma was 70 minutes. Fuel was used from the main tanks for the departure, climb, descent and arrival phases of the flight, and the auxiliary tanks were selected for the cruise. The pilot calculated the quantity of fuel used on the flight at the rate of 130 litres/hour, flight time. He estimated that 385 litres remained for the return flight to Moorabbin, which was planned for the evening of 18 September. His planned time intervals to Moorabbin, totalling 89 minutes, were calculated using a forecast wind of 250 degrees T at 30 kt. The flight plan fuel calculations allowed 15 litres for taxi, 15 % variable reserve, 15 minutes for an alternate, although no alternate was nominated, and 45 minutes fixed reserve. Flight fuel was again calculated at 130 litres/hour. The plan indicated that the fuel required, including these allowances, was 385 litres. Late in the evening the pilot prepared the aircraft for departure, but experienced difficulty when attempting to start the left engine. Unable to correct the problem, he deferred the flight until the next day.

The following morning the pilot obtained the forecast en route winds up to 10,000 ft, and the Moorabbin terminal aerodrome forecast (TAF). The forecast wind at 10,000 ft was 230 degrees T at 50 kt. The Moorabbin TAF included intermittent periods with wind gusts to 48 kt, 4,000 m visibility, 5 octas of cloud at 1,200 ft and hail showers. No other information was requested or given. The forecast required that the pilot allow for 30 minutes holding and the much stronger head winds indicated that the en route time would be significantly extended. However, without making any changes, the pilot re-activated his flight plan from the previous night.

Having obtained advice from the aircraft operator the pilot was able to start both engines without further difficulty, and departed Cooma on climb to cruise at 10,000 ft. Other than during cruise when the right auxiliary fuel tank was selected to the right engine for about 10 minutes, the flight was conducted on the main tanks. The left auxiliary tank gauge was indicating almost empty.

The pilot extended his estimated time intervals when strong headwinds were encountered during cruise. At about Eildon Weir he requested the actual weather at Moorabbin and was advised that the sky was clear. He assessed that the remaining fuel was sufficient and elected to continue. The Moorabbin Automatic Terminal Information Service (ATIS) information Tango indicated that the wind was 170 degrees M at 20 kt to 30 kt, gusting to 45 kt, with a crosswind of up to 10 kt, and 4 octas of cloud at 1,500 ft, with lower patches and showers in the area.

At about 5 km from Moorabbin the left engine surged and failed. The pilot assessed that the problem was fuel related and selected the left auxiliary tank, which restored power to the engine. By this time, he had extended the landing gear and lowered 15 degrees of flap. With runway 17L in sight, the pilot continued the approach and selected 25 degrees of flap. The tower controller advised that a squall was approaching the airfield, and the pilot recognised that this may nesessitate a go-around. On final approach at about 1.5 km from the aerodrome at a height of about 300 ft to 500 ft, the left engine failed again. The pilot increased power on the right engine but did not feather the left propeller. He assessed that the aircraft could not reach the runway and altered heading to the left, intending to land on a grassed area of the airport which he considered was within range. The pilot had not told the tower controller of either the engine failure or of his intention to land on the grass. Consequently, on seeing that the aircraft was low and well to the left of the runway, the controller instructed the pilot to go around.

At a very low height of possibly 10 ft to 20 ft, the pilot applied full power to the right engine and selected the landing gear and flaps up. The airspeed was about 94 kt, the single engine best rate of climb speed. However, with the left propeller windmilling, little altitude was gained and the airspeed decayed below 94 kt. While drifting to the left, the aircraft tracked across the airport in a south-easterly direction towards an industrial estate. The aircraft passed very low over some buildings and with the stall warning sounding, it grazed a roof and collided with two trees before impacting the ground in a steep nose-down attitude.

The pilot and the front-seat passenger were trapped in their seats by the deformation of the forward fuselage and instrument panel. The three other passengers were able to evacuate the aircraft by the main cabin door.

Wreckage examination

The aircraft had tracked about 080 degrees M from the first contact with a factory roof to where it came to rest about 80 m further on. The impact caused substantial disruption of the fuselage nose section and the left wing. Both engines were torn from their mountings.

Less than 1 litre of fuel was obtained from the left main tank. No fuel was found in the left auxiliary tank. Thirty litres were obtained from the right main tank and 8 litres from the right auxiliary tank. The reason for the engine starting difficulty was identified and found to not affect the operation of the engines or the fuel flow at engine power settings above idle. No defects were found that might have contributed to the development of the occurrence.

Performance calculations indicated that at the time of the approach, the aircraft was capable of climbing on one engine. However, this was dependent upon the correct procedures being followed, including feathering the propeller of the inoperative engine. The aircraft loading complied with the requirements of the Flight Manual.

Pilot qualifications and experience

The pilot held a Commercial Pilot Licence with a Multi-engine Command Instrument rating. He also held a Grade 2 Instructor rating with a recently granted approval to conduct multi-engine aircraft training. He had logged a total of about 1,100 hours, including about 150 hours on multi-engine aircraft. The flight to Cooma was intended to further his experience.

The pilot's PA 31 endorsement training was conducted about 6 months before the accident. The training included engine failures after take-off and single engine approaches during which he had been instructed that the minimum safe altitude from which to conduct a single-engine go-around was 300 ft.

Engine fuel flow management

During the endorsement training, the endorsing pilot cited an example of a PA 31-310 which he knew to have an average or block fuel consumption of 140 litres/hour. Subsequently, the pilot hired VH-NNN from another operator who conducted a check flight with him. The instructor drew the pilot's attention to a placard which had been placed in the aircraft. The placard listed take-off, climb and cruise power settings. It also gave an exhaust gas temperature (EGT) setting of 1,400 degrees for the cruise. The pilot understood that the owner wanted these settings to be strictly followed. On subsequent flights in VH-NNN the pilot complied with the placarded power settings, including setting the EGT to 1,400 degrees F. The aircraft's engine management instrumentation included electronic digital fuel flow indicators, in addition to the standard fuel flow gauge. However, the pilot was not instructed in the use of the digital indicators.

The PA 31-310 Pilot Operating Handbook provides information on fuel mixture leaning procedures. The handbook indicates that for best economy the mixture should be set at peak EGT, provided 1,650 degrees F is not exceeded. To obtain the best power fuel flow setting, the handbook recommends setting the fuel flow to achieve an EGT of 125 degrees less than peak EGT. The best power fuel flow is considerably greater than that which results from the use of the best economy setting. Consequently, many operators use fuel flow settings between best power and best economy, typically 50 degrees F less than peak EGT.

The setting of 1,400 degrees as placarded, did not necessarily provide the pilot with a reference for peak EGT, which may vary between engines. By not establishing the reference peak EGT, the pilot did not verify the relevance of the 1,400 degree setting to the required fuel flow. The aircraft owner advised that the placard had been fitted for his own reference only.

Following analysis of information from previous flights of VH-NNN, and testing of the left digital fuel flow indicator, the investigation found that the standard fuel flow gauges were not accurate. Fuel consumption was calculated using the digital flow indicators, together with the manufacturer's information on fuel consumption for take-off, climb and descent. These indicated that the left engine required a total fuel consumption for the flight to Cooma and return to Moorabbin of almost all the fuel in the left main tank and the 50 litres added to the left auxiliary tank. However, the fuel flow achieved by setting the mixture control to 1,400 degrees EGT was higher than would have occurred using the best power setting.

By not establishing the fuel quantity on board prior to take-off from Cooma, the pilot was unable to confirm the fuel consumption rate for the engine settings used, and the actual fuel available for the return flight. However, he was confident that the aircraft contained sufficient fuel for the flight. His decision to not add fuel at Cooma was also influenced by his concern for better aircraft performance in the event of an engine failure.

Final flight path

Airport tower personnel reported that the aircraft initially appeared to be established on final for runway 17L. However, it then became apparent that the aircraft had deviated to the left of the extended runway centreline. The deviation to the left continued after the pilot was instructed to go around. The flight path carried the aircraft past the threshold of runway 17L in a shallow arc, briefly paralleling runway 13L, before crossing the aerodrome eastern boundary.

The difference in distance to run between the grass area nominated by the pilot, and the threshold of runway 17L, was found to be minimal.

ANALYSIS

Appropriate pilot decision making and adherence to established procedures are vital to the effectiveness of the response to an emergency situation. The circumstances of this occurrence did not reflect a standard of operational practice and decision-making consistent with the qualifications held by the pilot. This is apparent both in his flight fuel management, and in his response to the resulting asymmetric condition.

Fuel management

The pilot's fuel management relied on assumptions of fuel flow rates, placing an undue reliance on a block fuel consumption rate of 130 litres/hour, and on leaning the mixture to 1,400 degrees EGT. While these parameters may individually be appropriate in other circumstances, he did not verify that they were valid for this flight. By not confirming the aircraft's fuel state at Cooma, the pilot could not have known if sufficient fuel remained, and that his fuel management was appropriate.

Despite the forecast of winds considerably stronger than those for which he had planned, and the requirement to allow for possible holding at Moorabbin, the pilot did not reassess his fuel requirements or use a more appropriate engine management technique. He recognised that the initial failure of the left engine was due to fuel exhaustion and that the left auxiliary tank, which he then selected, contained little fuel. However, he did not appear to realise that a further failure of either or both engines due to fuel exhaustion could be imminent.

Asymmetric operations

The pilot demonstrated a lack of understanding of the fundamentals of multi-engine aircraft performance. This is evidenced by his not feathering the left propeller, his inability to maintain the aircraft on the runway alignment during approach, and his non-adherence to a decision height.

Following the first failure of the left engine, the pilot did not appear to understand the need to minimise drag and conserve height until assured of a safe landing. Although unable to maintain directional control during the approach, and despite having assessed that the aircraft had insufficient performance to reach the runway threshold, the pilot attempted to go around. Had he recognised the importance of nominating and maintaining a decision height, he would not have attempted to comply with the instruction to go around.

It is likely that the pilot's decision to land on the grass was made as a result of inadequate asymmetric technique rather than inadequate aircraft performance.

CONCLUSIONS

Findings

1. The pilot was appropriately licenced to conduct the flight.
2. The aircraft weight and balance were within the Flight Manual limitations.
3. The pilot did not allow for the provision of holding fuel and did not replan for the stronger headwinds and the resultant greater total fuel consumption.
4. The pilot did not establish the actual quantity of fuel on board the aircraft prior to departure from Cooma.
5. The aircraft fuel flow gauges provided erroneous readings.
6. The pilot was not familiar with the operation of the digital electronic fuel flow indicators and did not reference them during the flight.
7. The pilot did not establish whether the fuel flow management settings shown on a placard in the aircraft were appropriate to the flight.
8. The left engine failed at a late stage of the landing approach due to fuel exhaustion of the left main and auxiliary tanks.
9. The pilot did not advise the Moorabbin tower controller of the engine failure.
10. The prevailing wind conditions increased the pilot's workload.
11. The tower controller instructed the pilot to go around when, during final approach, the aircraft deviated from the runway alignment.

Significant factors

The following factors were considered relevant to the development of the accident:

1. The pilot did not ensure that the aircraft contained sufficient fuel for the flight.
2. The pilot did not establish that the engine control settings used were appropriate for his planned fuel consumption rate.
3. After the failure of the left engine the pilot did not maintain directional control of the aircraft.
4. The pilot made an inappropriate decision to attempt to go around from a very low height and did not feather the left engine propeller.

SAFETY ACTION

The investigation found that there are no specific CAR or CAO requirements with respect to essential training or testing prior to granting a multi-engine training approval. During the investigation of another occurrence (9402804) similar safety deficiencies were identified.

There is no approved or prescribed syllabus of training, or training approval test requirements for these aircraft categories. It is not a requirement to demonstrate to a CAA FOI or an approved ATO, knowledge and understanding of all systems and procedures essential to the safe operation of the aircraft, in all flight regimes, prior to the granting of a check and training approval.

Under CAR 217, a pilot is not required to hold an instructors rating in order to hold a check and training approval. Such approval is covered by the delegation under Part 5 of the CARs and includes the delegation to conduct training for endorsement and also to issue a certificate of endorsement. The delegation leaves the test requirements and parameters to the discretion of the testing FOI.

As a result of the investigation into occurrence 9402804 the Bureau issued interim recommendation IR950063 to the Civil Aviation Authority. It stated:

The Bureau of Air Safety Investigation recommends that the Civil Aviation Authority provide a syllabus of prescribed test requirements as a standard for the testing of an applicant for the granting of a check and training approval on a specific aircraft type. The test should ensure that the applicant has adequate knowledge and understanding of all systems essential to the safe operation of the aircraft, in all flight regimes, and that the applicant has the ability to pass on such detail to a student.

The CAA response stated:

Guidance on the conduct of check pilot approvals including flight test requirements are contained in MAOC Vol 1 Part A Ch 10 Appendix C3.  The Authority agrees with this recommendation and has commenced a project to produce a standard flight test report form for candidates, both instructors and trainers, seeking multi-engine training approval. In support of this form the Authority will also produce a syllabus and a test-conduct guide.

The Bureau has classified this response as CLOSED/ACCEPTED.

During cruise the pilot stated that the aircraft had experienced stronger than expected headwinds, so he allowed the left fuel tank to run dry in order to maximise endurance before changing to the right tank, the contents gauge of which indicated about 6 US gallons remaining.

A few minutes later the engine failed, and although the pilot performed all the necessary emergency procedures, he was unable to restore power.

He made "Mayday" transmissions on the Area and CTAF frequencies, then looked for a clear area to carry out a forced landing. There being no suitable areas within gliding range he was committed to stalling the aircraft into the treetops. The emergency locator beacon activated.

An investigation of the aircraft revealed there was no fuel in the left tank, and as the right tank had suffered damage at impact it was not possible to determine if there had been fuel in it prior to the accident. Fuel stains were noted behind both tank filler caps, indicating that some fuel syphoning may have occurred in flight.

The pilot had planned to carry out a short cross-country flight from Wedderburn via Goulburn, Taralga and Mittagong before returning to Wedderburn. He said that he had owned the aircraft for about eight years and was very familiar with its operation. On the morning of the flight, he measured the fuel contents of the left and right fuel tanks using a wooden dipstick and found that each tank contained 92 litres of AVGAS. From his experience, the normal fuel consumption was 37 litres/hr.

The flight to Taralga was uneventful in clear but turbulent weather conditions. However, as the aircraft tracked towards Mittagong the engine suddenly lost complete power. About one minute earlier the pilot said he had detected a slight amount of rough running and had used carburettor heat for about 30 seconds, without any change being noticed. When the engine lost power he was at a height of about 1500 feet above ground level. Despite changing fuel tanks, and turning the fuel boost pump on, power was unable to be restored. Due to limited height the pilot had to attempt a forced landing onto a steeply sloping field with rocky outcrops. Shortly after touching down the landing gear struck an outcrop and was torn off, stopping the aircraft from continuing into a valley. Both the pilot and his passenger were unharmed.

Although the total flight time had been about 61 minutes the left fuel tank was subsequently found to have been empty at the time of the accident. The engine was later able to be started and run. The pilot was unable to account for the apparent loss of fuel.

FACTUAL INFORMATION

The aircraft was making its last spray run before refuelling when it suffered a loss of engine power. The pilot climbed the aircraft while attempting to restart the engine.

When the engine failed to respond, a forced landing was carried out into a paddock but during the landing roll the aircraft entered a 2-metre-deep ditch at low speed, causing damage to the propeller and left wingtip.

Subsequent inspection revealed that while there was a small amount of fuel in one wing tank, the header tank feeding the engine was empty.

ANALYSIS

When the aircraft type was originally designed, it was fitted with a radial piston engine. A turboprop engine was fitted to later models, and the fuel system was redesigned with a small header tank in the fuselage between the wing tanks and the engine. The header tank should supply fuel to the engine for a short time if the tank outlets become uncovered by fuel during manoeuvring with small amounts of fuel remaining.

If the fuel supply to a turboprop engine is interrupted and then restored, the engine is not likely to restart without action from the pilot unless an automatic re-ignition system is installed. There was no such system on the accident aircraft.

Other similar engine failures have been experienced with this type of aircraft due to the location of the fuel tank outlet, which can become uncovered when the fuel level in the tank is low, and the aircraft is in a nose-down attitude.  This was the most likely situation which led to interruption of the flow of fuel to the header tank and to the engine of VH-ODR.

SIGNIFICANT FACTORS

1. The aircraft was operating with a small amount of fuel in the wing tanks.
2. Although there was some fuel in one wing tank, the header tank feeding fuel to the engine was empty probably because a nose-down attitude allowed the tank outlets to become uncovered.
3. The engine failed, probably because of fuel starvation, at too low a height for the pilot to effect a restart.

SAFETY ACTION

As a result of the investigation into this and a subsequent occurrence (BASI No. 9601185, VH-XST), the Bureau of Air Safety Investigation forwarded the following Safety Advisory Notice to the Civil Aviation Safety Authority (CASA) on 1 July 1996.

SAN960052

The Bureau of Air Safety Investigation suggests that the Civil Aviation Safety Authority, in consultation with the US Federal Aviation Administration (FAA), review the fuel system design of aircraft conforming to Type Certificate A17SW to ensure the adequacy of the fuel system with all applicable airframe/engine combinations.

The CASA response dated 18 July 1996 stated in part: 'I have written to the President of Air Tractor, and the Small

Airplane Directorate of the Federal Aviation Administration, advising them of the fuel starvation incidents in

Australia and asking for their comments.  I will advise you of the responses when I receive them.'

The pilot was conducting a charter flight involving four legs. He was familiar with the routes being flown and carried fuel sufficient to complete all legs without refuelling.

It was the pilot's normal fuel management practice to fly the first leg on the left tank and change to the right tank prior to landing. He would then fly the next leg on the right tank and change to the left tank for landing. This procedure was normally used for each of the remaining legs.

During the second leg the pilot forgot to change to the left tank for landing. He did not recognise his error until taxiing for departure for the final leg to Kununurra. At that point the pilot was uncertain as to the exact contents of each tank although it was evident that the left tank contained significantly more fuel than the right. He decided to fly the final leg using the contents of the right tank with the intention of changing to the left tank for the landing. The pilot was not in the practice of changing fuel tanks during transit due to the inhospitable terrain in the Kimberley region.

The engine stopped, due to fuel starvation, as the aircraft entered the circuit for a low-level approach. The pilot selected the left hand tank, which contained almost two hours of fuel, but the engine did not restart before the pilot was forced to manoeuvre for an abnormal approach and landing. The aircraft was landed across the runway, and the impact was sufficiently hard to cause the mainwheel legs to splay, the nosewheel leg to collapse and the bottom of the fuselage and the propeller to contact the ground. The aircraft stopped within the runway flight strip and the occupants evacuated uninjured.

The aircraft fuel gauges were serviceable, and the aircraft was fitted with a fuel calibration card.

The investigation determined that the pilot did not use a fuel logging system other than a very general mental tally of fuel used. The sequence of events indicates that the pilot failed to complete his pre-landing checks on at least two occasions as he did not change the fuel selector to the fullest tank for landing as was his normal practice. Other evidence indicated that although the fuel gauges were serviceable the pilot ignored their indications because he considered them unreliable. The company provided a fuel dip stick which the pilot did not use even when he became unsure of the actual fuel contents because he thought he had sufficient knowledge of the fuel state. Finally, the pilot was not concerned that the engine might stop as a result of fuel starvation because his experience led him to believe that it would restart quickly once a tank, with fuel in it, was selected.

The pilot was very familiar with the route flown and it is probable that he had become complacent about fuel management.

The pilot had developed a habit of completing a low-level circuit as he believed it assisted his control of aircraft speed. It is possible that the pilot's decision to conduct a low-level circuit contributed to the accident. Had the aircraft been at normal circuit height there may have been sufficient time for the engine to respond to the alternate fuel tank selection.

The operator's check and training system did not disclose the pilot's apparent complacency or unusual circuit procedures as he had performed more than adequately on check rides.

On 14 August 2013, at about 0830 Central Standard Time, the pilot of a Beech BE58 aircraft, registered VH‑ECL, was preparing for a charter flight from Tindal to the Borroloola aeroplane landing area (ALA), Northern Territory.

Using the operator’s elected fuel flow rate for the aircraft of 125 L/hr, the pilot calculated that a minimum of 545 L of fuel was required. The pilot elected to carry 570 L. In preparation for the flight, the pilot referenced the flight data log, which indicated that about 267 L of fuel was on board the aircraft. Consequently, the pilot refuelled the aircraft, adding about 153 L into each of the main fuel tanks. The pilot then conducted fuel drains and found no contaminants present.

During the cruise, the pilot observed the fuel quantity gauge for the right main fuel tank reading zero, but the fuel flow, and engine temperature and pressure indications were normal. The aircraft landed at Borroloola and the passengers disembarked. The pilot re‑checked the fuel calculations and determined that there was sufficient fuel on board for the return trip. The pilot noted that the right fuel quantity gauge was still reading zero and the fuel quantity gauge for the left main tank was indicating about three-quarters full.

On the return flight, when about 50-60 NM from Tindal, the right fuel flow gauge dropped to zero. The pilot shut down the right engine, notified air traffic control and conducted a single-engine landing at Tindal.

This incident highlights the importance of establishing known fuel status regularly and the need to use multiple sources to determine fuel quantity. This is particularly important for determining accurate fuel flow rate calculations and when the fuel quantity on board can only be accurately determined when the fuel tanks are full.

Aviation Short Investigation Bulletin - Issue 24

What happened

On 8 June 2013, the pilot of a Bell LongRanger helicopter, registered VH-RHF, was conducting an aerial survey flight with four passengers in the Buccaneer Archipelago area north of Derby, Western Australia. The helicopter was being flown at about 1,000 ft to a planned fuel stop on an island in Cone Bay and was over water when the engine flamed out.
The pilot entered autorotation to glide towards land but was unable to reach it. During the glide the pilot deployed the helicopter’s pop-out floats in preparation for an emergency ditching. Shortly after touchdown the helicopter rolled inverted. The pilot and the four passengers exited without injury. A boat crew observed the emergency landing and rescued the occupants from on top of the upturned floating helicopter.

What the ATSB found

The ATSB found that, without the pilot realising, the fuel on board was probably sufficiently low to allow momentary un-porting of the fuel boost pumps, which interrupted the flow of fuel to the engine, resulting in an engine flame-out and ditching. Contributing to the pilot’s lack of awareness of the fuel state was a likely malfunction of the helicopter’s fuel quantity indicating system and a faulty low fuel caution system. In addition, the operator’s fuel management system was almost totally reliant on the fuel quantity indicating system and as a consequence, lacked a high level of assurance.

The ATSB also found that the guidance provided by the Civil Aviation Safety Authority in relation to pre-flight crosschecking of fuel on board allowed for a reliance on aircraft fuel quantity indicating systems without reference to independent sources of fuel quantity information.

What has been done as a result

The helicopter operator advised that as a result of this occurrence they have redesigned their fuel tracking form to improve usability. In addition, the operator is considering the fitment of a fuel totaliser to their LongRanger helicopter types.

Safety message

As shown by this and other occurrences, there is a need for operators to ensure that their fuel management policy and procedures provide for at least two independent and reliable means of establishing fuel on board. These should be supplemented by criteria for identifying, recording, and resolving any discrepancy between the amounts generated by the different methods. In situations where visual or other direct means of establishing fuel quantity are not possible, equipment that measures and totalises fuel flow can provide a valid basis for derivation of fuel on board.

Low fuel level caution systems are valuable elements in a safe fuel management framework but can fail without detection and should not be relied upon as a substitute for an independent crosscheck of fuel quantity indicating systems. Operators should consider the criticality of on-board fuel quantity measuring equipment in the context of their particular operations and manage the risk of malfunction accordingly.

On 31 August 2012, at about 1230 Eastern Standard Time, a Piper Seneca aircraft, registered VH-BTW (BTW) departed Hobart Airport, Tasmania for Bankstown Airport, New South Wales on a private flight under the instrument flight rules.  The pilot was the only person on board.    

Both engines stopped during cruise at 9,000 ft above mean sea level and 19 kilometres south of Nowra, New South Wales.  The pilot ascertained that the fuel selector for the right engine was in the cross-feed position and consequently both engines were drawing fuel from the left wing tank which was empty.  The pilot repositioned the fuel selector, was able to restart both engines and continued to Bankstown Airport. 

On landing at Bankstown, the aircraft had a significant lateral imbalance, as the left wing tank was empty and the right wing tank was almost full.  As a result, the aircraft departed the runway after landing.  The pilot regained control and the aircraft taxied to the parking area without further incident.  The aircraft was not damaged and the pilot was not injured.   

The incident highlights the importance of checklists in capturing errors made before and during flight and the need to conduct them diligently during all stages of flight. 

Aviation Short Investigation Bulletin – Issue 14

What happened

At about 1710 on 27 January 2012, a De Havilland Aircraft Pty Ltd DH-82A Tiger Moth aircraft, registered VH-GVA, took off from Maryborough Airport, Victoria, with two people on board.

Immediately after lift-off, the aircraft was observed to have a partial, intermittent power loss. The pilot continued the flight with the aircraft maintaining altitude or climbing slightly. At the upwind end of the runway, the aircraft made a climbing left turn before stalling and descending. The aircraft impacted the ground, and the occupants received fatal injuries.

The aircraft was seriously damaged by the accident forces and post-impact fire.

What the ATSB found

The partial engine power loss was probably a result of a partial blockage of the aircraft’s fuel cock. Although sufficient runway remained ahead to allow a safe landing, the flight was continued under limited power without gaining sufficient height to clear trees beyond the runway. Approaching the trees the aircraft climbed, lost airspeed, stalled and collided with terrain. There would have been a safer outcome had the pilot immediately landed the aircraft straight ahead.

Safety message

This accident illustrates several of the points made in the ATSB’s research report 

On 8 October 2011, a Cessna Aircraft Company U206F, registered VH-EUW (EUW), was conducting parachute operations at Tooradin aeroplane landing area (ALA), Victoria. At about 1415 Eastern Daylight-saving Time EUW was returning to Tooradin after a parachute flight that was rejected due extensive cloud cover.

When on final for runway 22 at Tooradin the aircraft lost power and collided with terrain approximately 0.75 nm northeast of the threshold in a tidal waterway. All 6 occupants were injured in the accident, the pilot and one skydiver seriously. The aircraft sustained serious damage.

As a result of the accident, the Australian Parachute Federation provided one mandated and a number of recommended safety actions to the aircraft operator which included: mandatory use of restraints below 1,000 ft above ground level; changes to the operator's flying operations manual to include roles and responsibilities of key personnel; increased training requirements and an expanded emergency procedures section.

This accident highlights the risks associated with engine failures at low altitudes.