Date: 201812
Local time of day: 1801-2400
Location: ATL.Airport, GA
Flight conditions: VMC
Light: Night
Aircraft: Regional Jet CL65; Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
Airspace: Class B ATL
ATC / advisory: Tower ATL
Second aircraft: A321
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Situational Awareness
Second reporter function: First Officer; Pilot Flying
Anomaly: Deviation - Speed All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Wake Vortex Encounter
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Regained Aircraft Control
Contributing factors: Environment - Non Weather Related; Procedure
Primary problem: Ambiguous

Narrative: Aircraft departed [RWY] 8R from ATL. Prior to our departure a B767 departed followed by an A321. At approximately 1000 FT AGL aircraft encountered heavy wake turbulence. Aircraft rolled approximately 45 degrees left and right followed by nose pitch up and down. Autopilot disconnected followed by master warning and stall warning. Airspeed was approximately 230 knots and dropped rapidly to 180 kts. Crew leveled wings pitched down approximately 3 degrees and prevented possible stall. Aircraft was unstable for about 1-2 seconds and made full recovery. Right engine had an ITT exceedance for less than 15 seconds. Crew immediately notified ATC of wake turbulence and immediately let ATC know we were correcting flight track to continue on assigned SID. Passengers given a quick explanation of event by Captain and checked with Flight Attendant (FA) to ensure everyone was ok. FA checked with passengers and verified no injuries. Company notified of incident by ACARS and continued to destination with no further events. Constantly be aware that wake turbulence could occur at any time or altitude. Crews must have constant situation awareness especially at peak departure times in high density airports.


Second narrative: I was the Pilot Flying (FO). Departed 8R behind A321 on POUNC2 Departure. Approximately 2;000 feet AGL experienced serious wake turbulence. This caused a course deviation due to momentary loss of control of aircraft plus wake turbulence avoidance immediately upon recognition of event. ATC notified of wake turbulence; he stated we had 4 miles in trail spacing. I'd say the event lasted (from start to finish) a total of 20 seconds. The autopilot (AP) kicked off; we received a master warning with no time to visually identify the EICAS warning. Immediately began correcting for aircraft control. I elected to offset to the right of course a tad; as the aircraft that gave us wake was making a left turn toward KLEGG on POUNC2 Departure. With the master warning; we received an aural warbler sound (stall?). No stick pusher or shaker activated.... I believe we also received a bank angle aural; with bank around 45 degrees. During this time; the aircraft felt out of my control for 2-3 seconds (my best guess) and the Captain and I were recovering from this wake turbulence encounter/master warning and warbler sound like as a stall recovery- at one point; our speed went from approximately 230 to 180 in a blink of an eye; lowered the nose; full thrust. At some point during full power; ITT exceeded on the right engine; I identified with a red arc. Captain informed ATC of the wake turbulence and about the obvious course deviation. No issues from ATC noted. No TA or RA observed. FDR EVENT was selected approximately 10 mins after recovery. Flight Attendant advised no injuries. ACARS sent to Dispatch and Maintenance to notify. We were informed to call duty manager and duty pilot upon landing and we did; Captain spoke with the appropriate people; including Maintenance regarding event. No aircraft damage noted during post flight walk around.


Synopsis: CL-65 flight crew reported loss of control for 2-3 seconds following a wake turbulence encounter departing ATL 4 miles in trail of an A321.