Following the 7 October 2008 occurrence, the aircraft manufacturer reviewed the FCPC algorithms for processing each ADIRU parameter on the A330/A340 aircraft. The review examined the amplitude, duration and frequency of data spikes that could potentially affect the FCPC’s control of the aircraft’s flightpath. In addition to data spikes, other potential incorrect data patterns were also considered. Based on this review, modifications were made to the algorithms for processing a number of the ADIRU parameters used by the FCPCs.
In addition to the A330/A340, the manufacturer also reviewed the algorithms used for processing ADIRU parameters by the flight control computers on the A320 and A380 aircraft.
The manufacturer also advised that it will apply the lessons learnt from the 7 October 2008 occurrence in terms of the types of incorrect data patterns to be taken into account during future design definition and modification. Accordingly, modifications were made to its guidance document ABD0200 (Guidelines and requirements for the system designers).