Narrative:

Intercept heading for final approach course was given by approach control with instructions to maintain 3000 ft till established, and to contact the tower. Crew began to configure the aircraft for landing and the PNF reading the final descent checklist, while the PF started the descent down the GS. 10 mi out tower called with warning to watch altitude. Altitude at that point was 2600 ft. GS altitude at the OM (6.8 mi) was 2898 ft. At that instance the flight director was showing a GS intercept with fly down commands. 2 contributing factors; the false command given by the flight director along with too much attention given solely to the checklist, and not backing up the pilot flying at this critical stage in the approach. As soon as the tower issued the low altitude warning the problem was discovered and a climb was initiated back to 3000 ft.

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Original NASA ASRS Text

Title: MLG ON APCH RECEIVES WARNING FROM TWR TO WATCH ALT. HAD FALSE GS INDICATION WITH FLY DOWN.

Narrative: INTERCEPT HDG FOR FINAL APCH COURSE WAS GIVEN BY APCH CTL WITH INSTRUCTIONS TO MAINTAIN 3000 FT TILL ESTABLISHED, AND TO CONTACT THE TWR. CREW BEGAN TO CONFIGURE THE ACFT FOR LNDG AND THE PNF READING THE FINAL DSCNT CHKLIST, WHILE THE PF STARTED THE DSCNT DOWN THE GS. 10 MI OUT TWR CALLED WITH WARNING TO WATCH ALT. ALT AT THAT POINT WAS 2600 FT. GS ALT AT THE OM (6.8 MI) WAS 2898 FT. AT THAT INSTANCE THE FLT DIRECTOR WAS SHOWING A GS INTERCEPT WITH FLY DOWN COMMANDS. 2 CONTRIBUTING FACTORS; THE FALSE COMMAND GIVEN BY THE FLT DIRECTOR ALONG WITH TOO MUCH ATTN GIVEN SOLELY TO THE CHKLIST, AND NOT BACKING UP THE PLT FLYING AT THIS CRITICAL STAGE IN THE APCH. AS SOON AS THE TWR ISSUED THE LOW ALT WARNING THE PROBLEM WAS DISCOVERED AND A CLB WAS INITIATED BACK TO 3000 FT.

Data retrieved from NASA's ASRS site as of July 2007 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.