Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical; Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Ground Event / Encounter Other / Unknown
Aircraft Aircraft Damaged; Flight Crew Took Evasive Action; General Declared Emergency; General Evacuated
Aircraft
We started the engines normally and turned off the DC ground power and indicated to the ground crew to remove the ground power cord. After the power was turned off and removed; the DC Bus light illuminated along with the loss of several cockpit lighting sources. I tried to reset the system with the bus reset switch and was unsuccessful. In preparation of shutting the engines down; I had the ramp personnel reconnect ground power. I turned the ground power switch on and moved the condition levers to fuel off; shutting down the engines. As the engines were spooling down; the ramp personnel were waving their arms to get our attention and they were pointing at the #1 Engine. I turned to look at the engine and saw heavy smoke and occasional sparks emanating from a vent on the inboard cowling of the #1 engine. My first officer and I decided that an evacuation out of the right side emergency exits was the best course of action and instructed him to enter the cabin and inform the flight attendant to commence with evacuation procedures out of the right side exits. With the presence of smoke coming out of the engine; I decided to empty the fire bottles into the engine as a safety precaution. After using the forward bottle and waiting 30 seconds; the smoke was still present so I used the aft bottle as well. I also informed ramp control to send the fire trucks as an added precaution. I then exited the flight deck into the cabin to assist with the orderly evacuation of the airplane. There was no pushing or running for the exits which was not needed as the only reason I decided to use the emergency exits was to keep the passengers away from the smoke coming out of the #1 engine. The first officer had already removed both right side emergency exits and was outside the right side forward exit assisting passengers out along with ramp personnel. Everyone evacuated safely out of the forward right side exit and proceeded into the terminal. The crew and I also exited the aircraft but stayed on the ramp as the smoke had all but stopped by the time everyone was out of the airplane. Hopefully it didn't exacerbate the problem; but the only item I would have done differently was not re-connect ground power when facing an electrical malfunction at the gate before shutting down the engines.
When inappropriate electrical anomalies resulted from the removal of ground power after engine start the Captain of a DHC-8 asked that ground power be restored.  When ramp personnel alerted the flight deck to smoke and sparks emanating from the left engine the engines were shut down; the passengers evacuated and both fire bottles were emptied into the left engine as a precaution.