Description

On 21 July 2007, an Airbus A320-200 being operated by Australian operator Jetstar on a scheduled passenger flight from Christchurch, New Zealand to Melbourne, Australia made a go around after an unsuccessful ILS approach to the destination runway in day Instrument Meteorological Conditions (IMC) because of insufficient visual reference at the applicable ILS Decision Height. The go-around procedure was not flown correctly and descent to within 38 ft of the ground occurred in fog before the required climb away was begun. A further unsuccessful approach with a correctly flown go around had then followed before a diversion to Avalon.

The Investigation

An Investigation of the event as a Serious Incident by the ATSB did not commence until 11 September 2007 and was prompted by media interest following the Operator’s failure to fully report the event. The Operator had no awareness of any event until a flight crew report was filed two days later and as this did not disclose the seriousness of the occurrence, this only became apparent during an internal investigation commenced on 2 August. The more serious nature of the event was not disclosed to the ATSB by the Operator until a request following the media interest referred to above.

The Investigation found that during the initial part of the missed approach with the AP remaining engaged, the aircraft commander as PF had not moved the thrust levers to the TO/GA position with the result that the aircraft automated flight mode did not transition correctly to Go Around. The flight crew had failed to notice and /or respond to this and descent towards the runway had continued at increasing airspeed for the next 8 seconds to a minimum recorded height of 38 ft above the runway before the aircraft responded to manual flight crew inputs and began to climb away, albeit erratically at first

It was noted that a procedure of moving the thrust levers to the TO/GA position for a short time and then retarding them to another position, colloquially referred to by some of the Operators’ pilots as a ‘TOGA tap’, was used widely by line and training pilots despite the absence of any approved procedure in the aircraft operating manuals by that name. The flight crew of the incident aircraft were aware of this ‘procedure’ - although it was not applied ‘correctly’ during their mis-flown go around. Operator management pilots told investigators that a ‘TOGA tap’ could be used to minimise the chances of exceeding flap limit speeds during a go-around.

It was also noted by the Investigation that Airbus had published a go-around procedure with the requirement to check and announce the aircraft’s flight mode as part of the initial actions of the go-around. That requirement was included to ensure that the crew could confirm the necessary changes to the aircraft’s flight mode. However, the aircraft operator had then changed that and moved the positive confirmation of the flight mode to a much later position in the procedure. The changed procedure required that a call be made only after a positive rate of climb was obtained. As a result, the aircraft continued to descend, with the crew distracted by unexpected warnings and a subsequently increased workload, this call did not occur and the crew never confirmed the correct aircraft flight mode.

The Investigation also noted that the aircraft operator had implemented a safety management system (SMS) that included a change management process. That process indicated that a change of this type to a standard operating procedure could be undertaken without a formal risk analysis. The investigation was unable to obtain any additional documentation from the aircraft operator in support of the change to the go-around procedure.

The Investigation also noted that initial aircraft type training for both the flight crew, who both had relatively low type experience had been provided by a Contractor using Airbus SOPs rather than those of the Operator with a subsequent ‘transition’ simulator session conducted by Operator to learn their specific procedures and checklists.

The Investigation Findings were as follows, quoted in full and unedited:

Contributing safety factors

• The pilot in command did not correctly move the thrust levers to the take-off/go-around position when carrying out the first missed approach procedure.
• The aircraft operator had changed the standard operating procedure for the go-around. The change resulted in the flight crew being unaware of the flight mode status of the aircraft during the first part of the first missed approach.[Significant Safety Issue]

Other safety factors

• The aircraft operator did not conduct a risk analysis when changing the go-around procedure, nor did its safety management system require one to be conducted. [Significant Safety Issue]
• Flight crew undergoing initial endorsement training with the third party training provider were not trained until later to the procedures and systems used by the operator. [Minor Safety issue]
• The aircraft operator did not comply with accepted document change procedures when modifying the standard operating procedure for the go-around. [Minor Safety Issue]
• There was no provision in the current CASA Regulations or Orders for third party flight crew training providers. As such, the responsibility for training outcomes were unclear. [Minor Safety issue]

Other key findings

• The aircraft operator did not comply with the incident reporting requirements of its safety management system, which was part of its operations manual, or with the reporting requirements of the Transport Safety Investigation Act 2003.

Safety Action taken during the Investigation and as a consequence of the occurrence included:

ATSB

Issue of a ‘Safety Advisory Notice’ to highlight the potential for unintended consequences when changes to standard operating procedures are introduced without first conducting an appropriate risk analysis.

Aircraft Operator

• The standard operating procedure for a go-around has been modified in line with the procedure promulgated by the aircraft manufacturer.
• A review of existing flight training arrangements is being conducted.
• Changes to document control procedures have been implemented to indicate when specific operator-initiated changes to procedures are made.
• Revisions have been made to the content of the SMS in respect of occurrence reporting.
• The SMS has been amended so that any change to an aircraft operating procedure requires the completion of a formal risk analysis prior to implementation.

Aircraft Manufacturer

The go-around procedure in the Airbus FCOM was revised to emphasise the critical nature of the actions by flight crew during a go-around.

Australian Civil Aviation Safety Authority

Noting the absence of regulatory clarity in respect of third party flight crew training providers, advice has been given of an intention to revise the applicable Regulations as a matter of priority.

The Final Report of the Investigation was published on 24 February 2010 and may be seen in full at SKYbrary bookshelf: Aviation Occurrence Investigation AO-2007-044 Final

No Safety Recommendations were made.

Further Reading

• Stabilised Approach
• Go-around from Low Airspeed/Low Thrust
• Flying a Manual Go-around