A B767-300 flight crew reported encountering wake turbulence from a preceding B757 that was eight mi...

Attributes
ACN	993025
Time
Date	201202
Local Time Of Day	1801-2400
Place
Locale Reference	IAD.Airport
State Reference	DC
Aircraft 1
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Aircraft 2
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 14000 Flight Crew Type 2500
Person 2
Function	First Officer Pilot Not Flying
Events
Anomaly	Inflight Event / Encounter Wake Vortex Encounter

Narrative:

While level at 7;000 ft; we encountered wake turbulence. We were level at 7;000 ft at a speed of 250 KIAS; approximately 8 miles behind a B757 also level at 7;000 ft. The autopilot was engaged as we encountered the wake turbulence. The aircraft began to roll right reaching a maximum estimated bank angle of approximately 15 degrees. At some point in the right bank; the stickshaker activated momentarily (less than a second). I disengaged the autopilot and rolled the wings level using ailerons alone; the aircraft responded immediately to aileron input. The entire event lasted about 3 seconds. No parameters or limits were exceeded and no altitude was lost.

Original NASA ASRS Text

Title: A B767-300 flight crew reported encountering wake turbulence from a preceding B757 that was eight miles ahead.

Narrative: While level at 7;000 FT; we encountered wake turbulence. We were level at 7;000 FT at a speed of 250 KIAS; approximately 8 miles behind a B757 also level at 7;000 FT. The autopilot was engaged as we encountered the wake turbulence. The aircraft began to roll right reaching a maximum estimated bank angle of approximately 15 degrees. At some point in the right bank; the stickshaker activated momentarily (less than a second). I disengaged the autopilot and rolled the wings level using ailerons alone; the aircraft responded immediately to aileron input. The entire event lasted about 3 seconds. No parameters or limits were exceeded and no altitude was lost.

Data retrieved from NASA's ASRS site as of July 2013 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.