Incident
On May 29, 2003, at approximately 14:15 local time, a Cessna 550B (registration EC-HRO) operating flight EXU-2159 from Barcelona to Málaga was cruising at flight level 290 after passing the Ebrox waypoint. The flight crew reported a strong odor and white smoke appearing on the right side of the cockpit. No warning lights illuminated and no circuit breakers tripped. The crew consulted the emergency checklist, donned oxygen masks, and requested clearance to land at Reus Airport. The smoke dissipated after a few minutes. The aircraft landed on runway 07 at 14:25 without incident. Weather conditions were CAVOK with calm winds; the approach was visual and normal. After vacating the runway and shutting down engines, passengers and crew evacuated without complications. The aircraft was towed to the hangar apron.
Investigation
Operator technicians arrived at Reus two hours after landing. They noted a persistent odor resembling an electrical short circuit emanating from behind the right-side instrument panel. Inspection identified the source as one of the internal cooling fans of the navigation display at the right pilot station. All wiring was visually inspected, equipment was removed and tested while running in the aircraft for several hours. The investigation confirmed that a short circuit in the fan integrated into the Honeywell navigation display (part number 7014300-901) caused the smoke. The display had been installed in September 2000, at the time of aircraft manufacture, and was identical to two other units in the cockpit. Its maintenance was defined as "on condition." The unit was sent to the manufacturer for further analysis of the fan short circuit. The display itself continued to function correctly due to redundant ventilation.
Aftermath
The following day, a replacement unit was obtained from the manufacturer and installed. Ground functional tests were satisfactory, and a test flight and repositioning to Barcelona were completed without issue. The aircraft was returned to service.