Narrative:

Ord runway 22L; ATIS wind 180@4. First officer takeoff. Shortly after takeoff power was set with N1's matched; airplane yawed abruptly left. First officer attempted to correct with right rudder. Aircraft didn't seem to respond at first and then yawed abruptly to the right. Captain took control and rejected takeoff at about 75 kts. We were able to taxi back to the gate without any other control issues. To me it felt like brakes were being applied on one rudder pedal at a time. I debriefed the first officer and asked if he might have been applying brakes while attempting to steer the aircraft during takeoff and he said absolutely not. He said his feet were low on the pedals.I was contacted by the foqa gate keeper as the lateral yaw triggered a foqa event. I explained to the gate keeper the facts of the event as stated above. I asked him to look at any technical data that he had available to see if there was any unusual brake applications during the takeoff roll. He said he could see none.coincidently; after telling the story of my rejected takeoff to my current first officer; he informed me that he has had the exact same thing happen to him on at least two separate occasions while departing runway 22L at ord. His events occurred following aircraft landing on 28C and suggested that what we may have felt was wake turbulence from the landing aircraft. In my event; I don't recall if an aircraft had just landed on 28C but it might be worth looking into and passing on to ATC at ord and other pilots.

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Original NASA ASRS Text

Title: B737-800 Captain reported the flying FO had directional control difficulties that led to a rejected takeoff on Runway 22L at ORD; wake turbulence from landing traffic traffic on Runway 28C was cited as a possible factor.

Narrative: ORD Runway 22L; ATIS wind 180@4. First Officer takeoff. Shortly after takeoff power was set with N1's matched; airplane yawed abruptly left. FO attempted to correct with right rudder. Aircraft didn't seem to respond at first and then yawed abruptly to the right. Captain took control and rejected takeoff at about 75 kts. We were able to taxi back to the gate without any other control issues. To me it felt like brakes were being applied on one rudder pedal at a time. I debriefed the FO and asked if he might have been applying brakes while attempting to steer the aircraft during takeoff and he said absolutely not. He said his feet were low on the pedals.I was contacted by the FOQA Gate Keeper as the lateral yaw triggered a FOQA event. I explained to the Gate Keeper the facts of the event as stated above. I asked him to look at any technical data that he had available to see if there was any unusual brake applications during the takeoff roll. He said he could see none.Coincidently; after telling the story of my rejected takeoff to my current First Officer; He informed me that he has had the exact same thing happen to him on at least two separate occasions while departing runway 22L at ORD. His events occurred following aircraft landing on 28C and suggested that what we may have felt was wake turbulence from the landing aircraft. In my event; I don't recall if an aircraft had just landed on 28C but it might be worth looking into and passing on to ATC at ORD and other pilots.

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.