In-flight upset - 154 km west of Learmonth, WA, 7 October 2008,

FAULT’ and ‘A.ICE *’ fault messages, and then reviewed all relevant PFRs indetail. 208 The samples searched were as follows:• 1 January 2002 to 31 December 2008, long range aircraft (A330, A340) withLTN101 ADIRUs: four events identified (three known events and one otherpotentially related event)• 1 January 2005 to 31 December 2008, long range aircraft (A330, A340) withanother ADIRU model: no related events• 1 January 2005 to 31 December 2008, single aisle aircraft (A310, A318, A319,A320, A321) with LTN101 ADIRUs: no related events.This search identified only one other potentially relevant event. That event involvedan A330-200 aircraft (registered VH-EBC) on 7 February 2008. The aircraftoperator (Jetstar) was associated with the operator of QPA, and the aircraft’smaintenance was conducted by the operator QPA. Although the PFR containedsome similarities with the three known events, a detailed examination of theavailable evidence concluded that this occurrence was unrelated to the three knowndata-spike occurrences. 209The aircraft manufacturer also conducted additional searches of the AIRMANdatabase for all A330s that were operated by the operators of QPA and EBA for theperiod 1 January 2002 to 31 December 2008. Those searches involved a variety ofdifferent combinations of faults. No other potentially related events were identified.208209These messages were considered to be the most effective search as A.ICE messages were notnormally associated with an IR or GPS problem. The common link between these differentsystems was an ADIRU and a problem with the ADIRU could be incorrectly indicated as bothA.ICE and GPS faults. Searching only for IR faults was unmanageable as there were too manypositive hits.For the VH-EBC event, a key difference was that the ADIRU BITE recorded an actual fault, andsubsequent examination of the ADIRU by the ADIRU manufacturer identified a hardware fault. Inaddition, the crew reported that they did not receive multiple or repeated ECAM warnings orcautions, and that the PFR did not contain distinctive messages associated with the failure mode(such as ADIRU maintenance status or NAV GPWS messages. No FDR or QAR data wasavailable.- 242 -