Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface; Training / Qualification; Troubleshooting; Confusion; Distraction
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types
Aircraft Automation Overrode Flight Crew; Flight Crew Became Reoriented; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Clearance
Aircraft; Weather
On takeoff; after rotation; the FMS apparently failed to sequence to the proper way point. At that moment we recognized that the flight director was not giving us correct information for navigation to intercept the first fix on the NUGGT Departure; 26L. Recognition of the failure was almost instantaneously perceived by the flight crew and also by ATC. ATC questioned our heading almost at the same moment that we advised ATC that we had an FMS failure and needed a heading to continue. All checklists prior to take-off and review of RNAV were done properly and completed. Heading bug was centered to runway heading and radio/ FMS were all in auto-tune. What we did not realize upon rotation and going WOW (weight off wheels); was that the FMS (for reasons I am still unsure about) did not sequence out the intercept fix and provide us with navigation to the next fix. It acted as if it was inhibited but upon crossing the intercept fix at approximately 600 FT; the flight director wanted to start a shallow turn to the left. As pilot flying I picked up the navigation error first and actually keyed the mike to advise ATC that there was a problem with navigation. Thereafter; the pilot not flying tried to sequence the FMS to the next fix and at this point; the FMS was indicating a turn to the left to re-intercept the course. We took headings for several miles and then re-sequenced the FMS in attempt to isolate problem. Tracking and sequencing the FMS thereafter indicated no faults. We never received any EFIS COMP messages or AHRS flags at any time. I am very confident that the FMS was in auto sequence and the only explanation I have been able to come to is that upon WOW; the FMS should have sequenced to the first fix and removed the intercept fix from the FMS. If it had been inhibited upon crossing the intercept fix; it should have continued to track runway heading. Instead; it wanted to come back to the fix using a left turn for unknown reasons. The wind could have been a possible factor in some of this due to northwest winds 310/26 G36 causing an extreme crab on takeoff along with moderate turbulence. We had an off-line jumpseater on board and once in-route; one of his first comments was; 'it was trying to turn us to the left.' I asked him if he saw anything out of the ordinary or abnormal that he recognized (being that he was trained on an aircraft with FMS) and his only statement was that they had had trouble with their FMS' sequencing out the intercept fix upon take-off. FMS failure to follow course the only undesired aircraft state was its heading which was corrected quickly with no conflicts with traffic. On all FMS departures; upon going WOW I am going to visually confirm that the FMS has dropped the intercept fix and has sequenced to the first named navigational fix on an RNAV departure.
[Narrative #2 contained no additional information]
After a CRJ200 departed on the ATL Runway 26L NUGGT RNAV in a crosswind; the FMS failed to track the departure path and commanded a left turn; but no errors were displayed nor did EFIS COMP MON alert.