B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 189.78; Flight Crew Type 2238.75
Situational Awareness
Inflight Event / Encounter Wake Vortex Encounter
Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action
Environment - Non Weather Related; Procedure
On arrival into DTW ILS Y 22R; we hit the wake of an airplane ahead of us. The auto pilot was engaged and I was the Pilot Flying. The flaps were at position 5 and we were in compliance with ATC directed airspeed (I think we were below 200 kts). At the time we hit the wake turbulence; the aircraft began quickly rolling to the right and by the time I intervened; we reached a maximum of 30-35 degrees right bank with virtually no change in pitch from a normal approach. I disconnected the auto pilot and rolled wings level. At no point during any phase of the flight did the aircraft get in an 'upset' state as defined by FM 4.70.7 (pitch; bank; and airspeed). The Captain notified ATC of the wake turbulence and inquired as to what aircraft was in front of us. ATC replied that we were following a 757; which was the first notification to us. ATC immediately asked if we had any injuries to which the Captain; upon confirmation with the flight attendants; replied 'no.' I believe the aircraft was about 3.5 miles ahead of us at the time. In the interest of safety and with ATC clearance; we broke off the approach and got resequenced with a right turn towards north and a small climb to 4;000 feet. The Captain assisted me (as I was hand flying the jet) with reprogramming the FMC and MCP. In addition to speaking with the flight attendants over the intercom (confirming the safety of passengers and crew/ everyone had been seated); the Captain also made a quick public address to announce what had occurred. This time around; we flew a normal approach to landing. After landing; we reaffirmed with the flight attendants that no one was injured.
B737-700 First Officer reported executing a go-around after encountering wake turbulence in trail of a B757 on arrival into DTW.