Narrative:

Approaching sfo, the ATIS indicated that VOR B approach in use VOR runways 10L&right. The surface winds were reported as southeast at 4 KTS. The ATIS remarks said that the wind at 1500 ft was 30 KTS. We talked about the VOR approach and the altitudes associated with it even though the sky was clear and the visibility was good. We also talked about the possibility of windshear. We were vectored to downwind and asked if we had the aircraft ahead in sight. We did, and we were then cleared for the visual approach to runway 10L. I turned final and lined up with runway 10L and began to descend using the PAPI. As we descended, the winds began increasing above 30 KTS. As the wind increased, I observed myself going high on the PAPI. I dropped the gear and flaps to recapture the glide path. We had light turbulence that caused vertical speed and airspeed fluctuations. As we crossed the coastline there is an area of high terrain. Over this area we got a GPWS 'terrain' warning. I was on the PAPI and noticed my vertical speed was about 1200 FPM descending. I concluded that the combination of my descent rate and the rapidly rising terrain cause a closure rate problem that set off the warning so I shallowed my descent. The terrain warning sounded again. I was still on the PAPI, the runway was in sight but I could no longer see the high terrain as it was beneath or behind us. At this point I observed my radio altimeter reading 850 ft. I began to add power and raise the nose as the warning sounded a final time. The tower issued us a low altitude warning and told us to check our altitude immediately. I never once recall being low on the PAPI throughout the entire approach. The aircraft was then restabilized prior to 500 ft and a normal landing was made.

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Original NASA ASRS Text

Title: B767-200 FLC EXPERIENCES MULTIPLE GPWS ALERTS DURING VISUAL APCH TO RWY 10L AT SFO.

Narrative: APCHING SFO, THE ATIS INDICATED THAT VOR B APCH IN USE VOR RWYS 10L&R. THE SURFACE WINDS WERE RPTED AS SE AT 4 KTS. THE ATIS REMARKS SAID THAT THE WIND AT 1500 FT WAS 30 KTS. WE TALKED ABOUT THE VOR APCH AND THE ALTS ASSOCIATED WITH IT EVEN THOUGH THE SKY WAS CLR AND THE VISIBILITY WAS GOOD. WE ALSO TALKED ABOUT THE POSSIBILITY OF WINDSHEAR. WE WERE VECTORED TO DOWNWIND AND ASKED IF WE HAD THE ACFT AHEAD IN SIGHT. WE DID, AND WE WERE THEN CLRED FOR THE VISUAL APCH TO RWY 10L. I TURNED FINAL AND LINED UP WITH RWY 10L AND BEGAN TO DSND USING THE PAPI. AS WE DSNDED, THE WINDS BEGAN INCREASING ABOVE 30 KTS. AS THE WIND INCREASED, I OBSERVED MYSELF GOING HIGH ON THE PAPI. I DROPPED THE GEAR AND FLAPS TO RECAPTURE THE GLIDE PATH. WE HAD LIGHT TURB THAT CAUSED VERT SPD AND AIRSPD FLUCTUATIONS. AS WE CROSSED THE COASTLINE THERE IS AN AREA OF HIGH TERRAIN. OVER THIS AREA WE GOT A GPWS 'TERRAIN' WARNING. I WAS ON THE PAPI AND NOTICED MY VERT SPD WAS ABOUT 1200 FPM DSNDING. I CONCLUDED THAT THE COMBINATION OF MY DSCNT RATE AND THE RAPIDLY RISING TERRAIN CAUSE A CLOSURE RATE PROB THAT SET OFF THE WARNING SO I SHALLOWED MY DSCNT. THE TERRAIN WARNING SOUNDED AGAIN. I WAS STILL ON THE PAPI, THE RWY WAS IN SIGHT BUT I COULD NO LONGER SEE THE HIGH TERRAIN AS IT WAS BENEATH OR BEHIND US. AT THIS POINT I OBSERVED MY RADIO ALTIMETER READING 850 FT. I BEGAN TO ADD PWR AND RAISE THE NOSE AS THE WARNING SOUNDED A FINAL TIME. THE TWR ISSUED US A LOW ALT WARNING AND TOLD US TO CHK OUR ALT IMMEDIATELY. I NEVER ONCE RECALL BEING LOW ON THE PAPI THROUGHOUT THE ENTIRE APCH. THE ACFT WAS THEN RESTABILIZED PRIOR TO 500 FT AND A NORMAL LNDG WAS MADE.

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.