Narrative:

On final for 17L; runway changed to 17R and had company 2.5 miles ahead. We were closing fast on company and were configuring to slow. First officer (pilot flying (PF)) called for flaps 30. I thought I had selected flaps 30; but was distracted by company ahead and our closure rate on him. First officer called for landing checklist and we both verified flaps at 30. At roughly 500 feet; we got a too low flaps warning. I checked the flap gauge; saw they were at 25; and moved them to 30. First officer confirmed and landing was uneventful. The approach was on speed and stable except for the flap setting.

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Original NASA ASRS Text

Title: B737 Captain reports being distracted by a late runway change; resulting in the final flap setting not being set until a 'too low flaps' warning is annunciated at 500 feet.

Narrative: On final for 17L; runway changed to 17R and had Company 2.5 miles ahead. We were closing fast on Company and were configuring to slow. First Officer (Pilot flying (PF)) called for flaps 30. I thought I had selected flaps 30; but was distracted by Company ahead and our closure rate on him. FO called for Landing Checklist and we both verified flaps at 30. At roughly 500 feet; we got a Too Low Flaps warning. I checked the flap gauge; saw they were at 25; and moved them to 30. FO confirmed and landing was uneventful. The approach was on speed and stable except for the flap setting.

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.