Introduction
On 21 August 2003, an Avro 146-RJ100, registration HB-IXW, operated by Swiss International Air Lines Ltd., experienced a directional control anomaly during approach to Zurich Airport. The aircraft was conducting a scheduled passenger flight from Dublin under instrument flight rules (IFR), with two pilots and 97 passengers on board.
Incident Description
Approaching runway 16 at approximately 1000 feet above ground, the aircraft abruptly yawed 45 degrees to the left. The crew applied full right rudder, which enabled them to land the aircraft on runway 16. After landing and taxiing, inspection revealed that the rod of the inner spoiler actuator on the left side was broken, and the associated spoiler was partially deployed. The aircraft sustained slight damage to the left-hand inboard flaps. No injuries were reported among crew or passengers, and there was no ground damage.
Investigation and Outcome
The Swiss Aircraft Accident Investigation Bureau (AAIB) opened an investigation. Because the technical issue became apparent immediately after the incident, the investigation focused on technical aspects. Immediate inspections, issuance of service bulletins, and an airworthiness directive (EASA AD 2006-139) followed. In the meantime, the technical issue was addressed fleet-wide by the authorities, the manufacturer, and operators. Consequently, the Swiss AAIB decided to cease the investigation, as the underlying problem had been rectified to an acceptable level of safety.