B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 76; Flight Crew Type 2284
Inflight Event / Encounter Wake Vortex Encounter
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification
Environment - Non Weather Related; Procedure
In descent from 9000 to 7000 with autopilot engaged hit by moderate jolt of wake turbulence. Continued descent and aircraft began to roll past 30 degrees angle of bank. Autopilot disengaged and aircraft rolled upright. Autopilot reengaged. Checked on flight attendants; all were ok. No passengers were up at the time. Enquired ATC about who we were following. Appeared to be a B777 ahead going to a different runway.
While descending from 9;000 to 7;000 we were given a turn to 170 for vectors to intercept the ILS 9R. In the turn; we experienced wake turbulence - with a bank angle approximately 30 to the right. The Captain disengaged the autopilot and hand flew the airplane back to level flight. I checked on the flight attendants to make sure they were all ok because it was so abrupt and sudden. All 4 of the flight attendants reported to me they were fine. Within a couple of minutes at 7;000'; we encountered wake turbulence again. This time it was a 40 - 45 degree bank angle to the right. My Captain was still hand flying and recovered the airplane. I asked ATC what type of aircraft we were following; the controller responded we weren't following anyone but there was a 777 ahead of us but 2;000' below us. The 777 was being vectored ahead of us for [RWY] 10C. Perhaps more spacing was required even though we were being vectored for different but parallel runways.
B737 flight crew reported encountering wake turbulence on arrival into ORD in trail of a B777.