A medium large transport encountered wake turbulence from a preceding heavy jet on descent into ord;...

Attributes
ACN	898250
Time
Date	201007
Local Time Of Day	1201-1800
Place
Locale Reference	ZAU.ARTCC
State Reference	IL
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Medium Large Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Aircraft 2
Make Model Name	Widebody Low Wing 4 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Not Flying First Officer
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 10300 Flight Crew Type 4000
Events
Anomaly	Flight Deck / Cabin / Aircraft Event Other / Unknown Inflight Event / Encounter Wake Vortex Encounter

Narrative:

During descent on wynde arrival to ord encountered wake turbulence at around FL200. Aircraft rolled each direction (left and right) approximately 20 degrees with the autopilot on and seat belt sign off. Immediately the seat belt sign was turned on. While listening to ATC it was obvious that we were following a heavy aircraft and this is what caused the wake turbulence event (in our opinion). This encounter lasted about 5 seconds. Rest of flight was normal and uneventful. During deplaning the last passenger (a female) reported an injury to her arm and shoulder and she stated that she was in the aft part of aircraft and was standing when the wake turbulence happened and that she was tossed against something on the aircraft and bruised her arm and shoulder. She walked off the aircraft. I notified the operations and dispatch and reported this issue.

Original NASA ASRS Text

Title: A medium large transport encountered wake turbulence from a preceding heavy jet on descent into ORD; resulting in a 20 degree roll in each direction. One passenger complained of an injury.

Narrative: During descent on Wynde Arrival to ORD encountered wake turbulence at around FL200. Aircraft rolled each direction (left and right) approximately 20 degrees with the autopilot on and seat belt sign off. Immediately the seat belt sign was turned on. While listening to ATC it was obvious that we were following a heavy aircraft and this is what caused the wake turbulence event (in our opinion). This encounter lasted about 5 seconds. Rest of flight was normal and uneventful. During deplaning the last passenger (a female) reported an injury to her arm and shoulder and she stated that she was in the aft part of aircraft and was standing when the wake turbulence happened and that she was tossed against something on the aircraft and bruised her arm and shoulder. She walked off the aircraft. I notified the Operations and Dispatch and reported this issue.

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.

A medium large transport encountered wake turbulence from a preceding heavy jet on descent into ord; resulting in a 20 degree roll in each direction. One passenger complained of an injury.