What happened
On 30 December 2014, a DHC-8-402 Dash 8, registration G-JECI, was performing a scheduled passenger flight from Southampton Airport to Belfast City Airport. The aircraft was carrying 69 passengers and 4 crew members. During the descent through FL150, the flight crew observed the smoke warning light illuminate on the flight deck panel, indicating a potential issue in the forward or aft baggage compartments.
In response to the warning, the commander instructed the first officer to don an oxygen mask. As the first officer complied, the smoke warning reappeared. The crew subsequently observed the extinguisher light for the aft baggage compartment illuminate, prompting them to discharge the fire extinguishant into that area. The commander issued a MAYDAY call and notified the cabin crew of a potential emergency, though the senior cabin crew member confirmed that no smoke was visible within the passenger cabin.
As the aircraft approached the runway, the smoke warning recurred. Despite attempts to contact the airport fire and rescue service for an external visual inspection of the baggage compartment door, the crew received no response. Upon landing at Belfast City Airport, the aircraft was brought to a halt and the engines were shut down. Following confirmation from Air Traffic Control that no external smoke or fire was visible, the commander ordered a rapid dismanubation. Due to a pre-existing unserviceability of the public address system, the crew utilized a megaphone to manage the exit of the passengers. There were no injuries and no damage to the aircraft.
The investigation
Investigators examined the aircraft's technical data, maintenance records, and the flight crew's reports. A physical inspection of the aircraft by the operator's engineering department found no evidence of actual fire or smoke damage. While the fire detection system initially appeared functional, the smoke detectors and the fire detection control amplifier were replaced as a precaution. A detailed strip examination of the smoke detectors revealed corrosion on an electrical connector pin within the smoke detector connection.