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.

On 29 September 2011, a Robinson Helicopter, R22 Beta II helicopter (R22), registered VH-RTB, was conducting aerial stock mustering operations about 43 km east-south-east of Maningrida, Northern Territory.

While guiding a herd of buffalo into the yarding area, at about 20 ft above ground level, the helicopter's tail rotor struck a tree. The helicopter landed heavily and sustained serious damage.

This accident not only highlights the challenging nature of aerial stock mustering operations, but also the benefits of utilising resources such as a ground support teams, when operating within the yarding area.

Preliminary report released 29 November 2011

On 1 October 2011, a Cheetah Sierra 200 aircraft, registered 24-7634, departed Taree Airport for the Old Bar Airstrip, New South Wales. On board were the pilot and a passenger. After arriving overhead the Old Bar Airstrip, the pilot conducted a left circuit followed by a touch-and-go landing on runway 17. The pilot then flew an additional circuit, from which a full-stop landing was planned.

On the second landing, the pilot estimated that he would not be able to stop before the end of the airstrip. As a result, the landing was aborted, and a go-around was commenced. During the initial climb phase of the go-around, the aircraft collided with a ferris wheel that was located to the south of the airstrip. The ferris wheel was part of a beach festival and, at the time of the collision, there were four people on the ferris wheel.

The aircraft and ferris wheel were damaged in the collision and the passenger and a person on the ground sustained minor injuries.

What happened

On 29 September 2011 at 1240 Central Standard Time, a Gippsland Aeronautics GA-8 Airvan, registered VH-AJZ, departed Marree, South Australia with one pilot and six passengers for a scenic charter flight over Lake Eyre and surrounding regions. About 45 minutes after take-off and while flying at a height of about 500 ft above ground level the pilot felt a shudder through the airframe, then heard a loud pop and the propeller stopped. The pilot carried out a successful forced landing on the Birdsville Track, approximately 135 km north-north-east of Marree.

What the ATSB found

The No. 5 piston of the aircraft’s single engine sustained a fatigue failure, resulting in severe mechanical damage that stopped the engine. The engine’s oil system was contaminated by metal chipping (spalling) from the bodies of two tappets because of contact fatigue to the tappets. This increased the risk of abnormal wear and failure of pistons and other engine components. The ATSB could not conclusively establish that this led to the piston failure, although similar failures in comparable engines had been attributed to that mechanism.

Although there was little warning to the pilot during flight of the impending engine failure, the operator had recently noted an abnormally high consumption of engine oil, which could have indicated poor engine condition. The oil consumption in fact exceeded the manufacturer’s limits for continued operation, but was misinterpreted, when referred to the maintenance organisation, as falling within those limits.

Finally, there was severe spline wear on the engine-driven fuel pump (EDFP) drive which could, if undetected, have led to EDFP drive failure and sudden loss of fuel flow to the engine, although this did not contribute to the occurrence.

What has been done as a result

The engine manufacturer had previously introduced a factory-fitted roller tappet to reduce spalling. Subsequently, for engines not yet incorporating that modification, the manufacturer introduced a flat tappet with an improved bonded coating, providing a more resilient sliding surface.

The aircraft operator reviewed the circumstances of this occurrence and has improved their monitoring of engine operating data, including oil consumption. 

Accelerated and abnormal EDFP spline wear in this engine type has been subject to ongoing study by the Civil Aviation Safety Authority (CASA). A number of failed EDFP shafts were examined by the ATSB in support of the CASA study.

Safety message

The investigation highlights the importance of operators monitoring and using engine oil consumption data as a diagnostic tool and of immediately investigating oil consumption figures that fall outside the manufacturer’s acceptable limits. Also highlighted are the importance of the engine manufacturer’s recommended oil filter inspections during scheduled maintenance and the associated guidance material when assessing any debris or contamination found.

On 26 September 2011 at 1151 Eastern Standard Time, the crew of an Airbus A321 (Airbus) aircraft, registered VH-VWW, received on the aircraft's traffic alert and collision avoidance system (TCAS) a traffic advisory (TA) alert, for an aircraft that was approaching from their front-right position at 2 NM (3.7 km) at 2,700 ft. The Airbus was maintaining 3,000 ft on an ARBEY standard terminal arrival route to runway 34 Left at Melbourne Airport, Victoria and was in Class C controlled airspace. The upper limit of non-controlled Class G airspace in the area was 2,500 ft.

It was later found that the pilot of the other aircraft a Piper PA-28-181 Archer, registered VH-TXD, had incorrectly set the aircraft's altimeter barometric pressure subscale setting, resulting in the aircraft entering controlled airspace without a clearance and a violation of controlled airspace occurring.

The occurrence was quickly resolved due to the traffic alert from the Airbus A321 aircraft's TCAS and the subsequent response from the flight crew.

This incident acts as a reminder to pilots of the importance to cross-check cockpit settings before flight.

At about 1142 Eastern Standard Time on 26 September 2011, two Beech A36 (Bonanza) aircraft, registered VH-IOL (IOL) and VH-YEN (YEN), operating under the Visual Flight Rules in G airspace, came into close proximity near Ravensworth, New South Wales, at 2,700 ft above mean sea level. The pilot of IOL was successfully alerted by Brisbane air traffic service (ATS), in time to see the other aircraft and initiate an avoidance manoeuvre. The pilot of YEN had not been monitoring that radio frequency and never saw the other aircraft. IOL was equipped with a portable collision avoidance system, but the pilot had switched it off because of ground-based machinery interference.

The chance of a successful avoidance manoeuvre was increased because one of the pilots had been successfully alerted by ATS. The alert occurred because both aircraft had transponders active on Mode C, enabling ATS to be aware of the proximity between the two aircraft.

The incident highlights the safety benefits for pilots to maintain an active listening watch on the appropriate radio frequency. Traffic information from any source can direct the attention of pilots to help them 'see-and-avoid' other aircraft in the vicinity.

On 22 September 2011, at about 1317 hours Western Standard Time (WST), a Cessna Aircraft model U206G (C206), registered VH-SHZ, departed Kalumburru Aerodrome, Western Australia (WA) with the pilot and six passengers on the return leg of a charter flight returning to Wyndham, WA. Following climb-out and in level flight at 5,500 ft above mean sea level (AMSL), the engine shutdown without warning. At the time of the engine shutdown, the right-wing fuel tank was selected and the right fuel quantity gauge indicated less that ¼ tank.

The pilot actioned emergency procedures including switching fuel tanks, and, at about 2,000 ft above mean sea level, the engine restarted. The flight continued on uneventfully and the aircraft landed at Wyndham. Post-flight inspection revealed that the pilot had not properly secured the right-wing fuel tank filler cap following refuelling that morning, resulting in fuel venting from the right tank.

On 25 September 2011, the pilot of a Cessna Aircraft Company 182, registered VH-MST (MST) was inbound to Toowoomba, Queensland (Qld) from Roma, Qld.  At the same time, a Schempp-Hirth Ventus 2c glider, registered VH-ULZ (ULZ) was competing in the Qld State Soaring championships and thermalling west of Toowoomba on track for Jimbour.

Whilst on descent through 4,000 ft the pilot of MST sighted a glider between 300 m and 500 m in front and at the same level.  The glider was heading directly for MST and the pilot was required to take evasive action. 

The distance between the two aircraft was estimated at 100m horizontally.

The incident highlights the need for pilots to apply the principles of 'see-and-avoid' in combination with an active listening watch on the appropriate radio frequency. Furthermore, simply having a radio is no guarantee of safety. It is imperative that pilots broadcast their position and intentions, for the performance of the more effective 'alerted see-and-avoid'.

On 27 September 2011, a flight instructor and student pilot of a Piper Aircraft Corporation PA 28 151 (Warrior) aircraft, registered VH-CIX (CIX), were conducting circuits at Mangalore Airport, Victoria. After completing a stop-and-go on runway 05 and climbing to 1,500 ft above mean sea level (AMSL), the aircraft was turned onto crosswind. When the turn was completed, the instructor of CIX observed a Piper Aircraft Corporation PA-44-180 (Seminole) aircraft, registered VH-KHG (KHG), on downwind, about 30 to 45 m to the right and at the same height. The instructor of CIX immediately assumed control of the aircraft, reducing the engine power to idle and descending about 200 ft.

The flight instructor and student pilot on KHG had joined downwind for runway 05 from a practice instrument approach to the Mangalore runway 23 very high frequency (VHF) omnidirectional radio range (VOR)¹. Soon after, the instructor sighted CIX off to his left flying straight and level, established on a slightly earlier than normal crosswind leg. CIX then passed in front of KHG, about 100 to 200 ft below and 100 m in front.

As CIX was straight and level and established on crosswind when first sighted by KHG, it is likely that the pilots of KHG did not sight CIX until after the airprox² had occurred and CIX had descended.

CIX and KHG were both operated by the same operator. As a result of this serious incident, the operator conducted an internal investigation into the incident and advised the ATSB that they had introduced a procedure whereby, when the wind conditions favoured a take-off towards the north or north-east, aircraft joining the circuit from a practice instrument approach were to descend to an overfly height of 2,000 ft AMSL and join the circuit from the non-active side of the circuit.

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1.      A ground-based navigation aid that emits a signal that can be received by appropriately equipped aircraft and represented as the aircraft's bearing (called a 'radial') to or from that aid.
2.      An occurrence in which two or more aircraft come into such close proximity that a threat to the safety of the aircraft exists, or may exist, in airspace where separation is a pilot responsibility.

At 0835 Eastern Standard Time on 26 September 2011, a flight instructor and student pilot in a Cessna Aircraft Company 152, registered VH-HCE, was operating at Bankstown Airport, New South Wales, on a training flight.

After a series of simulated rejected take-offs, the aircraft departed runway 11 to conduct circuits. After completion of the second touch and go, at a height of approximately 200 ft, the engine gradually lost power. The instructor resumed control, and with minimal runway remaining, and engine power further reducing, identified a suitable grassed landing area. The instructor declared a MAYDAY to air traffic control and positioned the aircraft for an emergency landing.

After the main wheels contacted the ground, and just prior to nose wheel contact, the engine power suddenly increased. The instructor reduced the throttle to idle and continued with the landing. As the nose wheel contacted the ground it detached, the aircraft nosed over and slid a short distance before coming to rest inverted. The instructor and student vacated the aircraft with no injuries.

A subsequent inspection identified a quantity of water in the right fuel tank that probably entered the tank via the right fuel cap receptacle following a period of heavy rain. Immediately following the accident, the operator conducted a fleet check, identifying an additional aircraft with water contamination in the fuel.

As a result of this occurrence, the aircraft operator advised the ATSB that they were taking the following safety actions:

• Instructor training on fuel system in Cessna aircraft type operated by the company;
• Student information sessions on water contamination incidents; and
• Compulsory instructor training.

This accident highlights that following periods of heavy rain, extra vigilance is needed during pre-flight checks to ensure that fuel is free of contamination.