A dhc-8-200 flight attendant reported the cabin filling with smoke shortly before smoke entered the ...

Narrative:

We had just left 14;000 ft descending to 9;000 ft. Not long after we started descending I noticed an odor in the cockpit. At first I thought the air conditioning had gone to full hot and was pumping out heat. I checked the duct temp and it was showing below 20 degrees. Right after that the flight attendant called and said the cabin was filling up with smoke. Shortly thereafter; smoke appeared in the cockpit coming through the first officer's lower air duct. We then proceeded to secure the aircraft and completed the required checklist to vacate the smoke. About 3 or 4 minutes had passed and the flight attendant reported no change in the amount of smoke in the cabin. With a major airport being the closest airport; we advised ATC of our situation declared an emergency. About 5 min from landing the flight attendant informed us the cabin was secure and that the smoke was finally clearing out. Landing was uneventful. After landing; the fire crew checked out the aircraft and we informed them that the smoke had stopped. We then taxied to the gate with the fire crew. Once at the gate passengers were met and brought into the gate area. All passengers appeared to be ok as they deplaned. No one was complaining about any health issues.I believe the smoke was coming from the bleed air system. Flight attendant notified us of the smoke in the cabin; we then proceeded to the checklist; shut down the bleed air system as we descended to 9;000 ft.

Original NASA ASRS Text

Title: A DHC-8-200 Flight Attendant reported the cabin filling with smoke shortly before smoke entered the cockpit during descent. An emergency was declared; the QRH completed and as the flight diverted to a nearby airport the smoke began dissipating.

Narrative: We had just left 14;000 FT descending to 9;000 FT. Not long after we started descending I noticed an odor in the cockpit. At first I thought the air conditioning had gone to full hot and was pumping out heat. I checked the duct temp and it was showing below 20 degrees. Right after that the Flight Attendant called and said the cabin was filling up with smoke. Shortly thereafter; smoke appeared in the cockpit coming through the First Officer's lower air duct. We then proceeded to secure the aircraft and completed the required checklist to vacate the smoke. About 3 or 4 minutes had passed and the Flight Attendant reported no change in the amount of smoke in the cabin. With a major airport being the closest airport; we advised ATC of our situation declared an emergency. About 5 min from landing the Flight Attendant informed us the cabin was secure and that the smoke was finally clearing out. Landing was uneventful. After landing; the fire crew checked out the aircraft and we informed them that the smoke had stopped. We then taxied to the gate with the fire crew. Once at the gate passengers were met and brought into the gate area. All passengers appeared to be OK as they deplaned. No one was complaining about any health issues.I believe the smoke was coming from the bleed air system. Flight Attendant notified us of the smoke in the cabin; we then proceeded to the checklist; shut down the bleed air system as we descended to 9;000 FT.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1156868
Time
Date	201403
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Dash 8-200
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

A dhc-8-200 flight attendant reported the cabin filling with smoke shortly before smoke entered the cockpit during descent. An emergency was declared; the QRH completed and as the flight diverted to a nearby airport the smoke began dissipating.