Description

On 24 August 2010, an Airbus A321-200 being operated by British Midland on a scheduled public transport service from Khartoum to Beirut experienced, during cruise at FL360 in night Instrument Meteorological Conditions (IMC), an electrical malfunction which was accompanied by intermittent loss of the display on both pilots’ Electronic Flight Instrument System and an uncommanded change to a left wing low attitude. De-selection of the No 1 generator and subsequent return of the rudder trim, which had not previously been intentionally moved, to neutral removed all abnormalities and the planned flight was completed without further event with no damage to the aircraft or injuries to the 49 occupants.

Investigation

A Field Investigation was carried out by the UK AAIB. The event was not reported promptly by the Operator and as a result both the Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) recordings were overwritten. Attempts to recover data from Non Volatile Memory in various equipment also failed because of this delay. However the QAR, powered by the No 2 Generator and recording similar data to the FDR, had continued to function during the incident and the routinely downloaded data from the flight was available for the Investigation. In respect of the delay in the reporting of the event to the AAIB, it was considered that the consequent delay in interviewing the flight crew “might have reduced the quality of their accounts”.