Narrative:

Due to metar winds at sjo showing 250/13; I focused on briefing the runway 25 RNAV visual procedure; an approach neither myself nor the first officer (first officer) had ever flown even though we had both been to sjo many times. We discussed the possibility of being switched to runway 07 by approach and the actions we would take in a compressed situation. I conducted what I felt was a very thorough briefing discussing all terrain and engine out issues. Additionally; due to the mention of -RA; much of our focus was on stopping distance on the ungrooved surface leading us to choose a flaps 40 app and auto brakes maximum. Thunderstorms (ts) were abundant in the area further complicating matters with ATC. We tried asking cenamer control which runway was in use; but could not get a response due to high traffic demand on the controller. After checking in with coco approach; we were cleared direct to parza and told to expect the ILS runway 07. Wind was now 250/10. Time was further compressed by the ts activity creating multiple traffic alerts and a late descent by approach. The necessary FMC changes were made; a quick approach brief was made and the approach checklist was completed. We intercepted the approach on speed and altitude; were stable within all flight manual parameters and had a visual of the runway and airport around 2500 feet AGL. At 500 feet AGL; while hand flying; I commented that even though we were on GS; the PAPI appeared to show 4 white lights and that we looked high as well. The first officer agreed and I chose to make the correction. At about 300 feet AGL we got a GPWS GS warning about the same time I began perceiving that we were in fact a bit low. The warning sounded 3 times while I was correcting and we landed within the touchdown zone about 1000 feet down the runway for a normal landing. During the rollout; it dawned on me that I had in fact read the NOTAM and even made a note on my control yoke scratch paper that the runway 07 PAPI was out of service but had forgotten about it. The time compressed briefing; flaps 40 landing attitude; a 10 knot tailwind; the natural visual illusion of appearing high on runway 07 and the blank PAPI lights that appeared to be all white when actually off; conspired to lead us both to the conclusion we should question the GS.

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Original NASA ASRS Text

Title: B737 Captain; on the ILS Runway 07 approach to MROC at 500 feet; reported seeing four white lights on the PAPI and ducks under the glideslope. A GPWS glideslope warning sounds at 300 feet and the reporter corrects back toward the glideslope and landing in the touchdown zone. The fact that the PAPI had been NOTAMed out of service had been forgotten.

Narrative: Due to METAR winds at SJO showing 250/13; I focused on briefing the runway 25 RNAV visual procedure; An approach neither myself nor the First Officer (FO) had ever flown even though we had both been to SJO many times. We discussed the possibility of being switched to RWY 07 by approach and the actions we would take in a compressed situation. I conducted what I felt was a very thorough briefing discussing all terrain and engine out issues. Additionally; due to the mention of -RA; much of our focus was on stopping distance on the ungrooved surface leading us to choose a flaps 40 app and auto brakes MAX. Thunderstorms (TS) were abundant in the area further complicating matters with ATC. We tried asking CENAMER Control which runway was in use; but could not get a response due to high traffic demand on the controller. After checking in with COCO approach; we were cleared direct to PARZA and told to expect the ILS RWY 07. Wind was now 250/10. Time was further compressed by the TS activity creating multiple traffic alerts and a late descent by approach. The necessary FMC changes were made; a quick approach brief was made and the approach checklist was completed. We intercepted the approach on speed and altitude; were stable within all Flight Manual parameters and had a visual of the runway and airport around 2500 feet AGL. At 500 feet AGL; while hand flying; I commented that even though we were on GS; the PAPI appeared to show 4 white lights and that we looked high as well. The FO agreed and I chose to make the correction. At about 300 feet AGL we got a GPWS GS warning about the same time I began perceiving that we were in fact a bit low. The warning sounded 3 times while I was correcting and we landed within the touchdown zone about 1000 feet down the runway for a normal landing. During the rollout; it dawned on me that I had in fact read the NOTAM and even made a note on my control yoke scratch paper that the RWY 07 PAPI was out of service but had forgotten about it. The time compressed briefing; Flaps 40 landing attitude; a 10 knot tailwind; the natural visual illusion of appearing high on RWY 07 and the blank PAPI lights that appeared to be all white when actually off; conspired to lead us both to the conclusion we should question the GS.

Data retrieved from NASA's ASRS site 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.