Abstract

At about 2307 on 6 September 2010 a safeworking irregularity involving freight train 2CM3 occurred at Bomen in New South Wales.

The network controller attempted to set the route for freight train 2CM3 to depart Bomen Yard and proceed onto the mainline towards Melbourne. The network controller was unable to change absolute signal BN27 from a stop (red) aspect to a proceed aspect (green), so he gave verbal authorisation to the driver of train 2CM3 to depart Bomen and pass signal BN27 while it was displaying a stop indication. However, issuing a verbal authorisation was not in compliance with the safeworking rules in this case. The network controller should have issued a written Special Proceed Authority (SPA) to authorise train 2CM3 to pass signal BN27 at stop.

The investigation found that a procedural error by the network controller was the main factor that contributed to the incident. There were no injuries or damage to rolling stock or other property as a result of the incident.

The Papua New Guinea Accident investigation Commission (PNG AIC) is investigating a runway excursion that occurred at Bwagaoia Aerodrome, Misima Island, Milne Bay Province, Papua New Guinea on 31 August 2010. The accident involved a Cessna Aircraft Company Citation 550, registration P2-TAA, with two pilots and three passengers on board. The aircraft landed at Misima Island and, when it became evident that the aircraft would not stop on the remaining runway, the pilot attempted a takeoff. The aircraft did not obtain flying speed before the end of the runway and was substantially damaged when it collided with trees shortly after. Four occupants sustained fatal injuries during the accident sequence and one occupant sustained serious injuries.

The investigation is being carried out in accordance with Papua New Guinea's obligations as the State of Occurrence under Annex 13 to the Convention on International Civil Aviation. Shortly after the accident, the AIC requested Australian Transport Safety Bureau (ATSB) assistance in the conduct of the investigation by providing investigator support, technical advice and facilities support.

In accordance with paragraph 5.23 of Annex 13, the ATSB appointed an accredited representative and a number of advisers to assist the AIC. To facilitate this support, the ATSB commenced an investigation under the Transport Safety Investigation Act (2003) and assisted the AIC during the on-site phase of the investigation, in the technical examination of a number of recovered aircraft items and components, and as requested by the AIC during the remainder of its investigation.

The PNG AIC is responsible for and will administer the release of the final investigation report into this accident. Any enquiries in respect of the ongoing AIC investigation should, in the first instance, be directed to:

Mr David Inau
CEO, Accident Investigation Commission
Telephone: +675 311 2406
Facsimile: +675 342 7727
E-mail: dinau@aic.gov.pg

Address:
Accident Investigation Commission
C/- PO Box 1489
Port Moresby
National Capital District
Papua New Guinea

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Released in accordance with section 25 of the Transport Safety Investigation Act 2003.

Preliminary report released 25 October 2010

On 30 August 2010 at approximately 2330 Pacific Daylight Time, a Boeing 747-438 aircraft, registered VH-OJP, departed San Francisco International Airport on a scheduled passenger service to Sydney, Australia. As the aircraft passed through 25,000 ft, the aircraft's number 4 engine sustained an internal mechanical failure, resulting in the energetic release of debris and puncturing of the engine casing and nacelle. The engine was shut down and the flight crew returned the aircraft to San Francisco, where it landed without further incident.

Updated: 29 August 2011

Disassembly and examination of the number 4, Rolls-Royce RB211-524 engine at Hong Kong Aero Engine Services Limited (HAESL) has been completed under supervision of ATSB investigators, as well as representatives from the engine manufacturer, airframe manufacturer, and aircraft operator. Based on the outcomes of the disassembly, numerous engine components were retained for further, detailed testing and analysis by the engine manufacturer.

The manufacturer's investigation has concluded that the fracture and release of a low-pressure turbine (LPT) blade was likely to have initiated the engine failure.  This produced rotor imbalance forces that resulted in significant damage to the LPT support bearing.  The bearing damage promoted additional secondary damage to core turbine hardware, to the extent that a turbine casing was ruptured, and low energy blade and nozzle guide vane debris was released.

An alternative bearing standard, which featured a more robust construction, had previously been introduced as an optional replacement part for reasons of continuity of supply for production. This bearing standard was not fitted in the event engine.  To minimise the risk of complications arising from rotor imbalance, the engine manufacturer is working with operators to embody this more robust bearing standard into engines, which, at the time of writing, is installed in more than 50% of the worldwide fleet.  The engine manufacturer has issued an Alert Non-Modification Service Bulletin (NMSB72-AG729) to instruct the installation of this improved bearing across the remainder of the fleet.   

Updated: 7 September 2010

The ATSB investigation team has completed its preliminary examination of the engine in San Francisco. The engine is now being shipped to an engine facility in Hong Kong for a detailed disassembly and examination, under the supervision of ATSB investigators. The investigation is ongoing and also includes:

• detailed analysis of recorded flight data, with particular focus on analysis of engine operational parameters
• examination of aircraft maintenance documentation
• interviews with crew and passengers.

This page will provide future updates on any significant developments as they come to hand.

On 30 August 2010, the pilot of a Robinson Helicopter Company R44 Clipper II, registered VH-ZVF, was intending to operate a private flight from Jandakot aerodrome to Hillside station Western Australia (WA).

Shortly after lift-off, control was lost and the main rotor blades struck the concrete apron adjacent to the departure helipad. The helicopter rolled and came to rest on its right side. The helicopter sustained serious damage and fragments of main rotor blade entered the hangar. Other fragments of main rotor blade were scattered over a large area of the aerodrome. The pilot sustained minor injuries while the passenger was uninjured.

Subsequently, the pilot reported he might have failed to turn the hydraulics on prior to lift- off. This may have been due to distraction created by a problem with a communications system and the unfamiliar departure sequence. The following ATSB publication provides some useful information on distraction:

• Dangerous Distraction: Aviation Research Investigation Report B2004/0324

For a full copy of that report, please visit the ATSB's website at www.atsb.gov.au

On 24 August 2010, a Boeing Aircraft Company 737-700 aircraft, registered VH-VBR, was being operated on a passenger flight between Sydney, New South Wales and Melbourne, Victoria.

During the descent into Melbourne, at about 900 ft, the aircraft encountered windshear, resulting in the airspeed increasing rapidly. The pilot in command (PIC) immediately initiated a missed approach in accordance with the operator's windshear escape manoeuvre. During the manoeuvre, the PIC observed a 'PULL UP' alert momentarily activate on the primary flight display (PFD).

As the crew was visual and a positive rate of climb established, the copilot believed that the windshear escape manoeuvre had been completed and the normal go-around procedure had been commenced. Consequently, the copilot selected 15 degrees of flap, the setting used when conducting a go-around, and queried whether the aircraft's landing gear should be retracted.

The aircraft was climbed to 5,000 ft and an approach and landing on runway 27 was conducted, without further incident. After landing, the PIC reported the windshear occurrence and possible flap overspeed to the maintenance engineers. An inspection of the leading and trailing edge flaps was carried out with nil defects found.

The Flight Safety Foundation states that flight crew awareness and alertness are key factors in the successful application of windshear avoidance and recovery techniques.

At about 0700 Western Standard Time on 16 August 2010, a Fairchild Industries Inc. SA226-TC (Metro II) aircraft, registered VH-NGX, departed Perth Airport on a charter flight to Fortnam Mine, Western Australia. On board the aircraft were the pilot and 10 passengers.

The aircraft was climbing through flight level 205 when the right cockpit side window suddenly failed and the cabin rapidly depressurised. The pilot put on his oxygen mask, activated the passenger oxygen system and transmitted a distress call to air traffic control. He commenced an emergency descent to 9,000 ft and returned to Perth. There were no reported injuries to the aircraft occupants and the aircraft sustained minor airframe damage as a consequence of the window failure.

The investigation determined that the window failed as a result of cracks that had propagated laterally between the retainer holes along the upper edge of the window and significantly weakened its structural integrity.

Inspection of the aircraft logbooks determined that the failed window was fitted as an outer window in 2006 by the previous aircraft owner. However, the investigation identified that the window was manufactured and supplied as an inner window only, was of reduced material thickness, and was not designed to safely withstand cabin pressurisation loads.

The work practices during the installation of the incorrect window and its reduced material thickness contributed to the window's deterioration and failure under pressurisation loads.

The investigation did not identify any organisational or systemic issues that might adversely affect the future safety of aviation operations. Notwithstanding, the aircraft operator and Civil Aviation Safety Authority initiated proactive safety action to minimise the risk of a recurrence of the window failure.

On 12 August 2010, a Cessna Aircraft Company U206F aircraft, registered VH-TZV, was conducting parachuting operations near Gladstone, Queensland. Soon after take-off, as the aircraft was climbing through 1,000 ft, the aircraft's engine lost power.

The pilot was unable to restart the engine and conducted an emergency landing in a field. The aircraft was significantly damaged and some of the occupants sustained serious injuries.

The reason for the engine failure could not be determined.

Pilots should consider the effect an in-flight engine failure at low altitude would have on the time available to manage the failure and identify a suitable forced landing area. In this instance, the pilot was able complete some emergency checks and turn the aircraft away from a water course in an attempt to conduct a forced landing on a gravel road. It is likely that this action positively influenced the outcome for the occupants of the aircraft.

At about 1545 Eastern Standard Time on 7 August 2010, while returning to Moorabbin Airport, Victoria after conducting aerial photography work, the pilot of a Cessna 152 aircraft, registered VH-KKW, experienced a total loss of power that resulted in an emergency landing approximately 200 m short of the airport. The aircraft was significantly damaged. The pilot and single passenger sustained minor injuries.

The investigation found that the pilot, when preparing for the flight, had misread the aircraft's initial fuel state and had subsequently uplifted a lesser quantity of fuel than required for the flight. Although the fuel remaining was greater than the manufacturer's stated unusable quantity, the investigation determined that the accident was the result of fuel starvation. The aircraft was prone to asymmetric fuel delivery allowing one tank to deplete quicker than the other. That action may have led to the aircraft unporting fuel from the low quantity tank during manoeuvring, which allowed air to be drawn into the engine. The investigation identified inconsistencies in the application of the operator's procedures for recording aircraft fuel states.

As a result of the accident, the operator re-designed the flight time and serviceability log to provide clearer application and recording of aircraft pre- and post-refuel fuel state. It also advised that it had: introduced a requirement that a formal 'Fuel Required' calculation be made for all flights leaving the circuit or training area, with a copy to be attached to the passenger list/weight and balance data; inspected the seat-locking mechanisms on all club aircraft and reminded all staff/students/members of the importance of ensuring all seats are locked; and reviewed training requirements for engine failure

Pilots are reminded that there is the potential for asymmetric fuel delivery on Cessna 152 aircraft and as well as monitoring fuel use, they need to be alert to such situations, particularly in minimal fuel states.

The ATSB has completed its examination of the cockpit voice recorder from a Sikorsky UH-60 helicopter, registered A25-204, on behalf of the Australian Directorate of Defence Aviation and Air Force Safety (DDAAFS). The helicopter had been involved in an air safety occurrence during a training operation on 23 July 2010.

The Australian Directorate of Defence Aviation and Air Force Safety is responsible for investigating this occurrence. On 10 August 2010, DDAAFS requested assistance from the Australian Transport Safety Bureau (ATSB) in the recovery of information from a cockpit voice recorder (CVR) that was fitted to the helicopter.

To protect the information supplied by DDAAFS to the ATSB, and the investigative work undertaken to assist the Directorate, the ATSB initiated an investigation under the Transport Safety Investigation Act 2003.

The CVR was successfully downloaded on 13 August 2010 and a copy of the data file was provided to representatives from DDAAFS. The CVR was returned to the DDAAFS representatives following the download.

Information publicly released by DDAAFS is available on the Department of Defence website: www.defence.gov.au

Contact details for DDAAFS are:

Air Force Headquarters
Department of Defence
Russell Offices
Canberra ACT 2600

Switchboard: (02) 6265 9111

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Released in accordance with section 25 of the Transport Safety Investigation Act 2003.

Abstract

At about 1121on 17 June 2010, a safeworking irregularity involving CityRail passenger service SN57 and train D231, a Pacific National light engine, occurred at Moss Vale in New South Wales. On the day of the occurrence, planned maintenance on the Argyle Street bridge, (southern end of Moss Vale) was being conducted in accordance with ARTC's SAFE Notice 2-1334/2010. By way of the SAFE Notice, the Australian Rail Track Corporation (ARTC) had promulgated that Down CityRail services would be routed from the Down Main via 140 points set reverse (an unsignalled movement) then terminate alongside the Moss Vale Up Platform before forming the return Up service to Campbelltown.

The investigation determined that the network controller, in error, gave the driver of CityRail passenger train SN57 verbal authority to pass signals MV15 and MV39 in the Stop position, over 140 points set reverse, to access the Up Platform at Moss Vale. A little earlier, the controller had authorised train D231 to travel into the Moss Vale Up Refuge Siding, also over 140 points, thereby placing the two trains into direct conflict.

Fortunately the network controller recognised the error and stopped train D231 about 200 m before 140 points, the potential point of conflict. There were no injuries or damage to rolling stock or infrastructure as a result of the incident.

The investigation established that an error by the network controller was the main factor contributing to the incident. However, the ATSB considers that the use of a checklist or similar systemic defence measure by network controllers for this type of working may enhance the integrity of ARTC's current safeworking arrangements.