Date: 201412
Local time of day: 0601-1200
Location: N90.TRACON, NY
Flight conditions: VMC
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach; Descent
ATC / advisory: TRACON N90
Second aircraft: B767 Undifferentiated or Other Model
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Inflight Event / Encounter Wake Vortex Encounter
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Environment - Non Weather Related; Procedure
Primary problem: Procedure

Narrative: During arrival into Newark we were on an assigned heading (approximating a downwind to 22L) when we started hearing a heavy also on the frequency.  Alerted to the presence of a heavy we noted an aircraft entering the downwind in front of us at our 12 o'clock and about ten miles maneuvering per the instructions of the approach controller issued to the Heavy.  We agreed that the 12 o'clock/ten mile target was likely the heavy and made a verbal note of this to each other.A few minutes later we encountered a strong jolt of momentary turbulence (in otherwise completely smooth air) and agreed that the preceding aircraft must be the heavy.  The heavy was given a series of headings in the direction of TEB while we were still on our original heading; so the Captain and I were satisfied with the separation that we had.Shortly thereafter we switched frequencies and the next approach controller started giving us headings which were bringing us closer and closer to the heavy however the controller was - initially- keeping us above its flight path.  Nonetheless we started discussing amongst ourselves how the controller was really chipping away at our spacing; and discussing RECAT distances.As we were approaching the heavy's flight path; the controller issued us a descent and as we descended we again went through the heavy's wake; this time a longer series of rolls and jolts as we crossed their path.  According to TCAS we were about seven miles behind now; but crossing its path at an oblique angle.The captain and I were both concerned about the spacing but since both wake encounters had thus far been at angles to the heavy's flight path we were comfortable letting the controller do his job and surmised that he was going to take us out for an extended downwind/base turn.Shortly thereafter the controller issued a turn to intercept the localizer and a descent to 2;500 feet which put us about five miles in trail.  With the recent issuance of RECAT we were skeptical but willing to initiate the approach as we now had a crosswind and the heavy should be in a dirty configuration.As we approached GIMEE we again entered into the heavy's wake just as the controller issued us an immediate turn to 180 for 'spacing'. I had disconnected the autopilot after we entered the wake turbulence and since the plane was already rolling to the left I simply continued the turn to the 180 heading.  A few moments later the controller issued us a turn back to 250 to intercept the localizer and continue the approach.As we approached the localizer we noted that we now had about seven miles on the heavy and both agreed to intercept the course and continue the approach using normal wake turbulence mitigation techniques (above glideslope).  However; agreeing that if we encountered even a burble we were going around.

Callback: Reporter stated that he questioned the FAA's inclusion of the B737 in the same wake category as the heavy; and also stated he wondered what the scientific basis of the RECAT program was.



Synopsis: B737 First Officer reported encountering wake turbulence in trail of a 'heavy' on approach into EWR.