Incident Overview
On 7 June 2009, a Boeing 737-800 aircraft, registered as D-AHLR, was involved in a serious incident at a location 65 NM on the 135° radial of the Geneva (GVA) VOR. The flight crew reported smoke emission in the cabin, prompting an emergency response.
Cause
According to the Swiss Accident Investigation Board (SAIB), the serious incident was caused by smoke emission resulting from a short circuit. The short circuit was traced to an assembly defect in the printed circuit board of an audio electronic box (SEB) installed under a passenger seat.
Technical Findings
Investigators examined the SEB audio electronic box and identified that the failure originated from a manufacturing defect in the printed circuit board. The defect led to an electrical short circuit, which in turn produced smoke. The smoke emission occurred without a fire, and the aircraft landed safely. The incident did not involve any injuries.
Reporting Authority
The investigation was conducted by the Swiss Accident Investigation Board (SAIB), which issued Final Report No. 2134. The report detailed the factual circumstances and concluded with the identified cause.