Narrative:

In level cruise at 7000' we got a red smoke emergency light. It came on for about 3 to 4 seconds then went back out and came back on again. (It did this for the remainder of the flight. On for a few seconds or minutes then out for a few seconds to a few minutes) we suited up and contacted the flight attendant who checked the baggage bin. She reported there was no signs of fire or heat but she did smell an electrical burning smell. We declared an emergency and asked ATC about the nearest airport. They told us the closest was about 30 miles away. We told them we would like to divert to that airport and asked what the weather was there. We were informed that the weather was winds variable at 3; light rain; 10 miles visibility; 1000 feet broken overcast at 2700 feet. Temperatures were 23/25. We were told the quickest way to the airport was a ILS xx but there were heavy to severe thunderstorms on the last 2 to 5 miles of the final to runway xx. We were also informed that the ILS yy was available with no storms. We requested runway yy and ATC vectored us for the ILS yy. We requested and were informed that the fire trucks would meet us on the runway to check out the fire situation. I informed the flight attendant that due to the weather conditions (moderate to heavy rain and thunderstorms in the area) she should be ready to evacuate but we would not be evacuating unless the fire department confirmed there was a fire. We landed about 10 minutes later in moderate to heavy rain. We stopped on the runway. Shut down the #1 engine and feathered the number 2 so the fire department could check out the baggage bin. We were informed that there was no signs of fire anywhere; and that we could proceed to the gate to unload where the fire department would do a more detailed check. We called operations; taxied to the gate and unloaded all the passengers. The fire department did a detailed check of the entire airplane and reported no signs of fire. While the fire department said they did not smell any smoke in the bag bay or any where else the ramp workers whom unloaded the luggage said that they did smell a electrical burning smell on the bags. We contacted dispatch and maintenance. Contract maintenance could not find any signs of burning or melted wires. I did find that communicating while suited up caused problems both in communications with ATC and with the flight attendant. I understand that smoke needs to be treated as serious. I am not sure why; with the airplane pressurized venting out the baggage bin and the smoke/smell only in the baggage bin; we needed to add the complication of harder communication to the emergency.

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Original NASA ASRS Text

Title: A DHC8-300 red SMOKE light alerted intermittently at cruise and although the Flight Attendant found no smoke or fumes in the cargo area the Captain declared an emergency and diverted to a nearby airport where maintenance could find no smoke source.

Narrative: In Level cruise at 7000' we got a red Smoke Emergency light. It came on for about 3 to 4 seconds then went back out and came back on again. (It did this for the remainder of the flight. On for a few seconds or minutes then out for a few seconds to a few minutes) We suited up and contacted the Flight Attendant who checked the baggage bin. She reported there was no signs of fire or heat but she did smell an electrical burning smell. We declared an emergency and asked ATC about the nearest airport. They told us the closest was about 30 miles away. We told them we would like to divert to that airport and asked what the weather was there. We were informed that the weather was winds variable at 3; light rain; 10 miles visibility; 1000 feet broken overcast at 2700 feet. Temperatures were 23/25. We were told the quickest way to the airport was a ILS XX but there were heavy to severe thunderstorms on the last 2 to 5 miles of the final to Runway XX. We were also informed that the ILS YY was available with no storms. We requested Runway YY and ATC vectored us for the ILS YY. We requested and were informed that the fire trucks would meet us on the runway to check out the fire situation. I informed the Flight Attendant that due to the weather conditions (Moderate to heavy rain and thunderstorms in the area) she should be ready to evacuate but we would not be evacuating unless the fire department confirmed there was a fire. We landed about 10 minutes later in moderate to heavy rain. We stopped on the runway. Shut down the #1 engine and feathered the number 2 so the fire department could check out the baggage bin. We were informed that there was no signs of fire anywhere; and that we could proceed to the gate to unload where the fire department would do a more detailed check. We called operations; taxied to the gate and unloaded all the passengers. The Fire Department did a detailed check of the entire airplane and reported no signs of fire. While the Fire Department said they did not smell any smoke in the bag bay or any where else the ramp workers whom unloaded the luggage said that they did smell a electrical burning smell on the bags. We contacted Dispatch and Maintenance. Contract Maintenance could not find any signs of burning or melted wires. I did find that communicating while suited up caused problems both in communications with ATC and with the Flight Attendant. I understand that smoke needs to be treated as serious. I am not sure why; with the airplane pressurized venting out the baggage bin and the smoke/smell only in the baggage bin; we needed to add the complication of harder communication to the emergency.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.