Narrative:

After takeoff we received several amber cas messages: right aoa heat; right static heat; right pitot heat; tat probe heat. The QRH procedures led switching the air data to the operable side; which was the captain's side. On downwind for runway 6 in bhm we reported the airport in sight level at 3;000 ft. Tower cleared us for approach with a warning about the towers ahead. We were both in terrain mode; and I had the towers in sight. The first officer lost sight of the towers in the turn because of the bank angle; but I was still able to see them. He selected 2;200 ft and began a descent in the turn and we received a 'caution obstacle' aural. I said I still have the towers in sight; continue further right turn. Fearing the message; the first officer began to level off to avoid the tower. This left us high on approach. To correct for being high we began to configure for landing. The first officer selected flight spoilers and flaps and gear on schedule. It was nighttime; and dark in the flight deck; and I was not aware spoilers were deployed. As we rolled out on final the shaker momentarily came on. Airspeed was approximately 160 KIAS with a vref plus five of 143. The shaker confused me at this airspeed; but I noticed the speed tape margin was very narrow (red raster above and below). I quickly glanced at the EICAS and saw the flight spoiler deploy message and alerted the first officer and we immediately retracted them at approximately 600 ft AGL. We did not execute a missed approach; but upon hindsight we should have. We think multiple factors came into play. Low ceilings and poor vectoring by ATC led us to a short approach (flying inside of the towers instead of the west). The 'caution obstacle' took our focus off of the approach and resulted in being high for the approach. We had some confusion with the air data computer failure. Since I was not aware of the flight spoiler deployment; I did not immediately react when the red raster got tighter on approach--my first thought with the stick shaker was an 'unreliable' system related to the failed air data computer. The single air data computer caused color malfunctions on the remaining displays (white altitude instead of magenta; for example). Windshear guidance; mach trim; isis; and several other systems were deemed 'unreliable' according to the QRH. We did not communicate the flight spoiler deployment; and no checklist requires a cas check before landing. The vector from bhm tower onto base leg turned us directly into the obstacle; which the first officer lost sight of on the turn. Perhaps flight spoiler deployment could be a callout. Cas could be checked on before landing checklist. Bhm approaches should be made to the west of the towers.

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Original NASA ASRS Text

Title: A CL-65 flight crew; cleared for a night time visual approach from a south downwind to Runway 6 at BHM; experienced an unstabilized approach when their ground track generated an EGPWS terrain warning for charted towers on the turn to base. Their recovery was; in turn; exacerbated by their failure to retract the previously extended spoilers which resulted in a momentary stick shaker.

Narrative: After takeoff we received several Amber CAS messages: R AOA HEAT; R STATIC HEAT; R PITOT HEAT; TAT PROBE HEAT. The QRH procedures led switching the Air Data to the operable side; which was the Captain's side. On downwind for Runway 6 in BHM we reported the airport in sight level at 3;000 FT. Tower cleared us for approach with a warning about the towers ahead. We were both in terrain mode; and I had the towers in sight. The First Officer lost sight of the towers in the turn because of the bank angle; but I was still able to see them. He selected 2;200 FT and began a descent in the turn and we received a 'Caution Obstacle' aural. I said I still have the towers in sight; continue further right turn. Fearing the message; the First Officer began to level off to avoid the tower. This left us high on approach. To correct for being high we began to configure for landing. The First Officer selected flight spoilers and flaps and gear on schedule. It was nighttime; and dark in the flight deck; and I was not aware spoilers were deployed. As we rolled out on final the shaker momentarily came on. Airspeed was approximately 160 KIAS with a Vref plus five of 143. The shaker confused me at this airspeed; but I noticed the speed tape margin was very narrow (red raster above and below). I quickly glanced at the EICAS and saw the flight spoiler deploy message and alerted the First Officer and we immediately retracted them at approximately 600 FT AGL. We did not execute a missed approach; but upon hindsight we should have. We think multiple factors came into play. Low ceilings and poor vectoring by ATC led us to a short approach (flying inside of the towers instead of the west). The 'Caution Obstacle' took our focus off of the approach and resulted in being high for the approach. We had some confusion with the Air Data Computer failure. Since I was not aware of the flight spoiler deployment; I did not immediately react when the red raster got tighter on approach--my first thought with the stick shaker was an 'unreliable' system related to the failed ADC. The single ADC caused color malfunctions on the remaining displays (white altitude instead of magenta; for example). Windshear guidance; Mach Trim; ISIS; and several other systems were deemed 'unreliable' according to the QRH. We did not communicate the flight spoiler deployment; and no checklist requires a CAS check before landing. The vector from BHM Tower onto base leg turned us directly into the obstacle; which the First Officer lost sight of on the turn. Perhaps flight spoiler deployment could be a callout. CAS could be checked on before landing checklist. BHM approaches should be made to the west of the towers.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.