A preliminary report by the ATSB into the four-fatality accident near Condobolin on 2 December indicates that there was no distress signal from the aircraft before it broke up in the vicinity of thunderstorms.
The Australian Transport Safety Bureau's Preliminary Aviation Safety Investigation Report into the Piper Chieftain aircraft accident near Condobolin, NSW also found that structural failure spread wreckage along a 4 km path.
An active frontal weather system, accompanied by a line of frequent thunderstorms, was passing through the Condobolin area at the time of the accident. There was no distress signal from the aircraft, which had been cruising at 10,000 ft and was about 54 km left of the planned track. The pilot had advised air traffic control that he was diverting left due to weather.
The aircraft was en route from Archerfield to Swan Hill on 2 December 2005. On board were two pilots and two passengers. The forecast weather was amended after the time of the aircraft's departure from Archerfield to include reference to a line of frequent thunderstorms slowly moving east within 111 km of a line from Cobar to Wagga. That line crossed the intended track of the aircraft. It has not yet been established if the pilot received the amended weather information.
Examination of the wreckage revealed that both wings had failed outboard of the engine nacelles and that the right engine had separated from the aircraft. Sections of the rudder and horizontal stabiliser had also separated. Some parts of the separated structure were retrieved from the wreckage trail for further examination. There was no evidence of hail or lightning strike damage to the available pieces of wreckage. The available evidence indicated that the engines were capable of normal operation prior to the break-up.
The investigation is continuing and will include detailed examination of the retrieved structural items, the weather information and conditions, recorded air traffic control radar and audio information, aircraft maintenance and pilot records.