Dash 8-100
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Landed in Emergency Condition; General Declared Emergency; General Evacuated
Aircraft
On a ferry flight we were getting delaying vectors when we noticed that the AUX Battery was starting to get warmer than usual. I asked Approach for priority handling which they gave us immediately. The memory items were performed for this situation and the Abnormal Checklist was run. After turning the AUX Battery off the temperature continued to rise illuminating the AUX BATTERY HOT warning light. This prompted us to declare an emergency. The Captain landed and we turned off on Taxiway F; shut the plane down in the hold block and evacuated. The fire and rescue crews met us in the hold block and confirmed with thermal imaging that indeed the battery was hot. The fire crews disconnected all batteries and the plane was towed to the gate. It was determined through keeping a normal scan going throughout the flight and with the aid of the caution/warning light system. I assume this was a case of battery thermal runaway. We did everything we could to stop it but it continued. Luckily we were very close to our destination and a suitable place to land promptly. After determining there was an abnormal situation standard procedures were adhered to. Memory items were performed; checklists were run and assistance from ATC and airport facilities was requested. I do not think this can really be avoided in the future unless there is some way to inspect or replace the batteries more frequently than they currently are.
DHC8-100 First Officer experiences an overheated AUX battery during a ferry flight. After turning the battery off the temperature continues to rise and an emergency is declared. After Landing and clearing the runway the crew exits the aircraft and the fire disconnects the batteries.