What happened
On 26 October 1999, a scheduled Lufthansa flight from Frankfurt to Barcelona, operating an Airbus A320-200 with registration D-AIPM, encountered an issue during the cruise phase at flight level 290. A cabin attendant detected an odor resembling burning electrical cables in the forward galley and immediately notified the flight crew. Upon inspection, the First Officer confirmed the presence of an electrical smell.
To address the situation, the Captain handed over control of the aircraft to the First Officer and attempted to locate the source of the odor. While the crew communicated to Air Traffic Control that the diversion to Geneva was due to a minor technical problem and electrical fumes, the controller provided priority landing assistance and alerted airport fire and rescue services. During the descent, the crew deactivated the power to the galley. Following this action, the odor dissipated, and the crew informed controllers that they intended to perform a precautionary landing to allow for maintenance inspections. The aircraft landed normally at Geneva-Airport, and although fire services followed the aircraft, there were no injuries to the 7 crew members or 114 passengers on board.
The investigation
The investigation was initiated by the Geneva airport authority and conducted alongside technical representatives from Lufthansa and Swissair. Investigators examined the aircraft's systems and conducted tests to replicate the reported issue. During the inquiry, the crew's extended use of the galley ovens successfully reproduced the electrical odor, although no visible smoke or fumes were observed during these tests.
Findings
Technical analysis identified a faulty oven heater relay located within the oven timer panel as the source of the odor. Specifically, investigators found that two wires connected to the relay were loose, which caused the electrical smell when the unit was powered. No evidence of arcing or heat damage was found on the components, and the aircraft had no prior history of similar incidents.