Narrative:

We were en route to gsp in poor WX (700 ft, 3/4 mi) with light rain and fog. Wind was out of the northeast, but the ILS was OTS on runway 3, and the WX was below our circling minimums (1000 ft, 3 mi). We therefore were offered either an NDB to MDA 770 ft or an ASR to MDA 740 ft. We took the ASR to runway 3. The approach was conducted flawlessly to the MDA, at which time the aircraft was fully configured to land with gear down, flaps 30 degrees, reference plus 20 KTS. The first officer then called 'approach lights in sight,' but they were off to the left, 10 O'clock , at about 1 1/2 mi. I felt that we were too high, too close, and not well aligned. The approach lights were the only visual reference. The runway and terrain were not in sight, and I was looking through rain and fog at the approach lights. I turned toward the lights, reduced power almost to flight idle, slowed to reference plus 10 KTS and descended rapidly. Then the GPWS went off (sink rate), the first officer called 'add power,' I went to about 50 percent power, stopped the sink, and leveled off alarmingly close to the approach lights (maybe 75 ft AGL)! We landed normally but may have scared a few passenger! In reviewing the event, the following conclusions/lessons learned were established: upon arriving at the MDA, we should have not left the MDA until aligned with the runway. The first officer was looking at a chart during the final descent. Since I was 'outside' the airplane, he should have remained 'inside' on the gauges. When beginning descent from the MDA, I should have used a normal (GS) power setting precluding a rapid descent. Any or all of these would probably have prevented premature flight into ground proximity. While we may also have 'missed' the approach, that would have been a better choice.

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Original NASA ASRS Text

Title: AT72 FLC RECEIVED A GPWS DURING A RAPID DSCNT BELOW MDA. VISIBILITY WAS LIMITED RWY REF TO APCH LIGHTS, ONLY.

Narrative: WE WERE ENRTE TO GSP IN POOR WX (700 FT, 3/4 MI) WITH LIGHT RAIN AND FOG. WIND WAS OUT OF THE NE, BUT THE ILS WAS OTS ON RWY 3, AND THE WX WAS BELOW OUR CIRCLING MINIMUMS (1000 FT, 3 MI). WE THEREFORE WERE OFFERED EITHER AN NDB TO MDA 770 FT OR AN ASR TO MDA 740 FT. WE TOOK THE ASR TO RWY 3. THE APCH WAS CONDUCTED FLAWLESSLY TO THE MDA, AT WHICH TIME THE ACFT WAS FULLY CONFIGURED TO LAND WITH GEAR DOWN, FLAPS 30 DEGS, REF PLUS 20 KTS. THE FO THEN CALLED 'APCH LIGHTS IN SIGHT,' BUT THEY WERE OFF TO THE L, 10 O'CLOCK , AT ABOUT 1 1/2 MI. I FELT THAT WE WERE TOO HIGH, TOO CLOSE, AND NOT WELL ALIGNED. THE APCH LIGHTS WERE THE ONLY VISUAL REF. THE RWY AND TERRAIN WERE NOT IN SIGHT, AND I WAS LOOKING THROUGH RAIN AND FOG AT THE APCH LIGHTS. I TURNED TOWARD THE LIGHTS, REDUCED PWR ALMOST TO FLT IDLE, SLOWED TO REF PLUS 10 KTS AND DSNDED RAPIDLY. THEN THE GPWS WENT OFF (SINK RATE), THE FO CALLED 'ADD PWR,' I WENT TO ABOUT 50 PERCENT PWR, STOPPED THE SINK, AND LEVELED OFF ALARMINGLY CLOSE TO THE APCH LIGHTS (MAYBE 75 FT AGL)! WE LANDED NORMALLY BUT MAY HAVE SCARED A FEW PAX! IN REVIEWING THE EVENT, THE FOLLOWING CONCLUSIONS/LESSONS LEARNED WERE ESTABLISHED: UPON ARRIVING AT THE MDA, WE SHOULD HAVE NOT LEFT THE MDA UNTIL ALIGNED WITH THE RWY. THE FO WAS LOOKING AT A CHART DURING THE FINAL DSCNT. SINCE I WAS 'OUTSIDE' THE AIRPLANE, HE SHOULD HAVE REMAINED 'INSIDE' ON THE GAUGES. WHEN BEGINNING DSCNT FROM THE MDA, I SHOULD HAVE USED A NORMAL (GS) PWR SETTING PRECLUDING A RAPID DSCNT. ANY OR ALL OF THESE WOULD PROBABLY HAVE PREVENTED PREMATURE FLT INTO GND PROX. WHILE WE MAY ALSO HAVE 'MISSED' THE APCH, THAT WOULD HAVE BEEN A BETTER CHOICE.

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.