Narrative:

We were given 7;000 ft to descend on approach into tri. We were held high on the approach and were descending 2;500 FPM to make a descent to the airport. At the time of approaching the airport; ATC called to point out VFR traffic in the area below. I was expecting descent lower as part of the call and allowed myself to get distracted from making company call of 'captured' as the autopilot captured and leveled off at 7;000 ft. At the same moment; captain; as pilot not flying; was looking up tower frequency; and talking with ATC about the VFR traffic. When I looked back at the display; the 7;000 ft armed altitude was gone from the autopilot yet 7;000 ft was still displayed I the altitude alerter. The aircraft was descending below 6;700 ft and I began to add back pressure to the yoke and turn off the autopilot as I questioned the captain had we been given lower; stopping the descent until I had confirmation. Captain answered 'no' and I began a climb back up to 7;000 ft. Before reaching 7;000 ft; approach cleared us lower; then for the visual as we had the airport in sight during the whole approach. Upon review; the captain warned that at a higher descent rate the autopilot may not be able to capture the altitude; hence; our required 'capture' call per company operations. We were initially assigned the southern runway but asked for the more direct northern runway; which might explain why approach had us higher than normal if we were to land on the northern runway. This calculation of descent and controlled airspeed distraction me from the task at hand. I have approximately 800 hours in the aircraft and haven't had a deviation prior to this event. I plan on sticking with the runway assigned and adding due priority to the required calls and altitude changes.

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Original NASA ASRS Text

Title: MLG flight crew overshoot their altitude on descent.

Narrative: We were given 7;000 FT to descend on approach into TRI. We were held high on the approach and were descending 2;500 FPM to make a descent to the airport. At the time of approaching the airport; ATC called to point out VFR traffic in the area below. I was expecting descent lower as part of the call and allowed myself to get distracted from making company call of 'Captured' as the autopilot captured and leveled off at 7;000 FT. At the same moment; Captain; as Pilot Not Flying; was looking up Tower frequency; and talking with ATC about the VFR traffic. When I looked back at the display; the 7;000 FT armed altitude was gone from the autopilot yet 7;000 FT was still displayed I the altitude alerter. The aircraft was descending below 6;700 FT and I began to add back pressure to the yoke and turn off the autopilot as I questioned the Captain had we been given lower; stopping the descent until I had confirmation. Captain answered 'No' and I began a climb back up to 7;000 FT. Before reaching 7;000 FT; Approach cleared us lower; then for the visual as we had the airport in sight during the whole approach. Upon review; the Captain warned that at a higher descent rate the autopilot may not be able to capture the altitude; hence; our required 'Capture' call per company operations. We were initially assigned the southern runway but asked for the more direct northern runway; which might explain why Approach had us higher than normal if we were to land on the northern runway. This calculation of descent and controlled airspeed distraction me from the task at hand. I have approximately 800 hours in the aircraft and haven't had a deviation prior to this event. I plan on sticking with the runway assigned and adding due priority to the required calls and altitude changes.

Data retrieved from NASA's ASRS site as of April 2012 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.