Flight Crew Air Transport Pilot (ATP)
Confusion; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Became Reoriented; Flight Crew FLC Overrode Automation; Flight Crew Returned To Clearance
Aircraft; Weather; Human Factors
While descending via the HYPER 4 arrival the FMS went into sequence inhibit mode (uncommanded) after MOWAT level at 5;000 FT. This caused confusion between the FMS map and our situational awareness which told us to descend down to 4;000 FT for the HUSEL restriction and the FMS which was telling us to stay at 5;000 FT. I had started to descend after MOWAT but as a result of the confusion quickly leveled off due to the FMS indicating 5;000 FT at the next fix. After a few seconds I determined the error with the FMS and had to do a rapid descent to make the HUSEL restriction; however this restriction was complied with. I am still unsure why the FMS went into sequence inhibit. Additionally and unrelated to the first automation error; during the visual approach into Runway 1R the autopilot had difficulty capturing the localizer due to a strong tailwind on base. This resulted in a significant deviation (half scale) towards the parallel runway before the deviation was corrected. The FMS error may have been caused by an error a few minutes prior where when attempting to sync the heading bug the heading mode on the FCP was hit instead; however this error was immediately noticed and corrected with no deviation from the desired flight path. This was the only abnormal event that occurred before the FMS error; but doesn't seem to explain what happened. The localizer capture error was caused by a strong crosswind on the final approach course. This type of error seems to occur on a regular basis if the autopilot is allowed to capture on its own.
CRJ200 First Officer describes some auto flight anomalies that are common and may be attributed to FMS and or autopilot design.