The Executive Director of the Australian Transport Safety Bureau has today authorised the re-opening of the investigation into the crash of Whyalla Airlines VH-MZK. This is to enable the ATSB to seek the assistance of the US National Transportation Safety Board (NTSB) to conduct further testing of the MZK left engine crankshaft, which is currently in the US, including destructive testing at the site of the fracture.
The ATSB did not undertake such destructive testing in its original investigation because the detailed tests that were conducted indicated no crankshaft material problems and the ATSB did not wish to unnecessarily damage important evidence.
Clause 5.13 of Annex 13 to the Chicago Convention, as enacted in Australia through section 19DF(1) of the Air Navigation Act includes the requirement that: "If, after an investigation of an accident, serious incident or incident has been completed, new and significant information relation to the accident, serious incident, or incident becomes available, the Director must (a) if the investigation was conducted by the Director - conduct a further investigation of the circumstances surrounding the accident serious incident or incident". The ATSB has been assisting with, and closely monitoring, the progress of the Whyalla Airlines inquest in South Australia with this in mind.
The issuance by US engine manufacturer Textron Lycoming on 16 September 2002 of 'Mandatory Service Bulletin' No.553 for the first time included the MZK left crankshaft serial number V537912936 among the list of crankshafts possibly affected by a materials problem in the crankshaft manufacturing process.
Prior to the Whyalla inquest hearings in the US, it was hoped and expected that comprehensive testing of the left crankshaft fracture site would be jointly agreed and undertaken by McSwain (on behalf of the relatives of the deceased) with Lycoming in a timely manner. The engines are in the US as part of civil damages proceedings. The Coroner and parties had agreed to a protocol regime to allow for destructive testing as required. On that basis, the ATSB was prepared to await the outcome and formally re-open the ATSB investigation only if a significant material defect was established.
Ongoing delay with such testing has led to ATSB formally re-opening the investigation based on the 16 September 2002 service bulletin alone. The ATSB has also been told that some US litigation settlements require that engine parts be destroyed - such a loss of evidence would, of course, undermine the current inquest and future aviation safety. ATSB wishes to ensure that every effort is made to test the crankshaft without delay to resolve the question of whether a manufacturing material problem was a causal factor.
The US NTSB has informally advised today that as the engines are in the US, it would be prepared to test the left crankshaft in its laboratories for a materials defect at the site of the fracture if the ATSB re-opens its investigation and requests this assistance under Chicago Convention protocols. The ATSB would do so following the SA Coroner's agreement. The NTSB will not become involved in Australian or US legal proceedings.