A DHC8 first officer encountered wake turbulence while following a B737 on approach.

Narrative:

I was the first officer and pilot flying [a] dash-8 with the autopilot engaged on right base leg vectors to join the ILS 06R at cyyz. We were level at approximately 4;000 MSL in smooth air and clear VMC conditions. A B737 was about 8 NM straight-line distance from us and had flown a similar path on vectors and was now established on the ILS 06R. Suddenly our aircraft rolled to the left. I quickly disengaged the autopilot and applied corrective control inputs to counter the roll. The airplane recovered to straight-and-level flight and the entire wake turbulence encounter lasted only a few seconds. We elected to fly one dot high on the glideslope to avoid another encounter. Once we landed; the captain; two flight attendants; and I debriefed the event. The flight attendant's reported that they were both standing in the aft galley and had to brace themselves from falling over. All passengers were seated and belted in preparation for arrival; no one was injured. The captain remarked that had I not been 'following through' on the controls and disengaged the autopilot; he believed the roll would have continued. Because the 'bank angle' warning tone did not sound we determined the bank never exceeded 45 degrees. Both the captain and I have experience flying in high density environments where aircraft separation is minimal. We were both surprised by this wake turbulence encounter.

Original NASA ASRS Text

Title: A DHC8 First Officer encountered wake turbulence while following a B737 on approach.

Narrative: I was the First Officer and pilot flying [a] Dash-8 with the autopilot engaged on right base leg vectors to join the ILS 06R at CYYZ. We were level at approximately 4;000 MSL in smooth air and clear VMC conditions. A B737 was about 8 NM straight-line distance from us and had flown a similar path on vectors and was now established on the ILS 06R. Suddenly our aircraft rolled to the left. I quickly disengaged the autopilot and applied corrective control inputs to counter the roll. The airplane recovered to straight-and-level flight and the entire wake turbulence encounter lasted only a few seconds. We elected to fly one dot high on the glideslope to avoid another encounter. Once we landed; the Captain; two Flight Attendants; and I debriefed the event. The Flight Attendant's reported that they were both standing in the aft galley and had to brace themselves from falling over. All passengers were seated and belted in preparation for arrival; no one was injured. The Captain remarked that had I not been 'following through' on the controls and disengaged the autopilot; he believed the roll would have continued. Because the 'BANK ANGLE' warning tone did not sound we determined the bank never exceeded 45 degrees. Both the Captain and I have experience flying in high density environments where aircraft separation is minimal. We were both surprised by this wake turbulence encounter.

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.

Attributes
ACN	938979
Time
Date	201103
Local Time Of Day	0001-0600
Place
Locale Reference	CYYZ.Airport
State Reference	ON
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Dash 8 Series Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	B737 Undifferentiated or Other Model
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Multiengine Flight Crew Commercial Flight Crew Instrument
Experience	Flight Crew Last 90 Days 202 Flight Crew Total 2352 Flight Crew Type 470
Events
Anomaly	Inflight Event / Encounter Wake Vortex Encounter