Date: 201501
Local time of day: 0601-1200
Location: ATL.Airport, GA
Flight conditions: IMC
Weather elements / visibility: Turbulence
Light: Night
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class B SFO
ATC / advisory: Tower ATL
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Fatigue; Situational Awareness; Other / Unknown
Second reporter function: Captain; Pilot Flying
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Flight Deck / Cabin / Aircraft Event Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Contributing factors: Human Factors; Weather
Primary problem: Human Factors

Narrative: During rotation from RWY 9L in ATL the captain immediately went IMC due to poor weather conditions. The captain was the pilot flying. Upon entering IMC conditions the Captain experienced the leans and started drifting to the left of course. We were assigned the DAWGS (RNAV) departure with the first fix of LIDAS. Immediately the first officer reported 'left of course turn right' soon after ATC inquired about our heading and the wind. They immediately assigned a heading of 120. A correction by the captain was established when the first officer told the captain he had the leans. After that the first officer reported the wind; which was not a factor. (The winds were calm to 10 knots) Soon after a heading of 140 was assigned. Once on the assigned heading the after takeoff checklist was completed. We were then given direct DAWGS.This was our last leg of the day; it was night; low IMC; and we had an early duty in. We were left of course and corrected to prevent a lateral deviation into the other controller's airspace. As pilot monitoring I feel that I should take the controls from the captain; because he had a delayed response in correcting his lateral deviation.


Second narrative: FLIGHT Delayed; due to weather; push off gate taxied out to runway. Everything was done correctly all checklists were run all procedures complied with. After rotation I noticed the heading was not on runway heading and manually flew runway heading and prompted the first officer to center the Heading bug. When he didn't react immediately I look over to the left and made a rather fast head movement. This caused me to briefly experience the leans and I inadvertently banked to the left and got off the runway Heading. I caught it but we had drifted left of course. I was already correcting when Tower controller told us to turn left right to a heading of 120 and he informed us we were well left of course. We turned to this heading and cleaned up airplane. Several threats existed. Late in day 11 hours duty. Night time with low visibility and ceilings. Runway light brightness appeared a little disorienting to me as well. First Officer displaced not familiar with Atlanta Operations. We were not rushed; so this is not a factor. I believe the main reason we deviated was because I checked on first officer to see what he was doing and I should not have turned my head to do that. Check heading bug before takeoff and do not look at anything but the instruments on the rnav departure.


Synopsis: CRJ-200 flight crew with the Captain flying reports drifting left of course on takeoff from Runway 9L at ATL due to entering IMC at rotation. The heading bug had not been set to runway heading prior to takeoff and the Captain became slightly disorientated.