The Australian Transport Safety Bureau (ATSB) is to re-open its investigation into the crash of a Whyalla Airlines Piper Chieftain on 31 May, 2000,which killed the pilot and all seven passengers in a night ditching following a double engine failure.
It is now known that one of the aircraft's crankshafts comes from a batch identified in a Textron Lycoming mandatory service bulletin published after the accident about engines possibly affected by a materials problem in manufacture.
Although several similar incidents in the USA have been blamed on faulty materials, Whyalla was the first fatal accident linked to Textron Lycoming's recall of crankshafts. The ATSB had originally attributed the failure to high combustion pressure caused by pre-ignition and the manufacturer's use of an anti-galling compound at assembly.
Meanwhile an expert witness at a coroner's inquiry has stated that the crankshaft failure in the left engine was probably caused by faulty manufacture, contradicting the advice that the ATSB had been given by its metallurgist during the investigation.
The airline and the families of the deceased passengers are now preparing legal action against Textron Lycoming. The ATSB says it is reopening the investigation and is asking the US National Transportation Safety Board (NTSB) to conduct destructive testing of the left engine crankshaft.
The Bureau says it "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".
Source: Flight International
