Narrative:

I was the pilot flying (second leg on the first day of a three-day). We were deviating 10 degrees left of track for weather and descending through 17;000 feet for 11;000 feet and slowing working our way to on the arrival. Without warning; the APU fire warning light and bell came on. The APU switch was off. We had used it twice that day on the ground with no problems. The pilot monitoring did the recall items and the QRH and the fire light did not extinguish. We declared an emergency with center and were cleared direct to the field. I put the point prior to the FAF in the box and executed it. The approach and landing were normal. Tower stated that the runway was ours and we could stop right there. We stopped and set the brakes and got in touch with the fire department. They stated that they did not see any smoke or fire. The APU fire light was still on and the fire department had an airstair nearby. The captain shut down the engines and we ran the evacuation checklist. I proceeded to the front door and helped the passengers out of the aircraft and down the stairs to the side of the runway where the fire department had set up a safe area. Buses came out within 10 minutes. We counted heads as the passengers boarded three buses and put an flight attendant on each bus.

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Original NASA ASRS Text

Title: A B737-300 flight crew experienced an APU fire warning on descent into destination. They declared an emergency and after landing evacuated the passengers via the air stairs when fire crews reported no visible smoke or flames.

Narrative: I was the pilot flying (second leg on the first day of a three-day). We were deviating 10 degrees left of track for weather and descending through 17;000 feet for 11;000 feet and slowing working our way to on the arrival. Without warning; the APU Fire Warning light and bell came on. The APU switch was OFF. We had used it twice that day on the ground with no problems. The pilot monitoring did the Recall items and the QRH and the fire light did not extinguish. We declared an emergency with Center and were cleared direct to the field. I put the point prior to the FAF in the box and executed it. The approach and landing were normal. Tower stated that the runway was ours and we could stop right there. We stopped and set the brakes and got in touch with the Fire Department. They stated that they did not see any smoke or fire. The APU fire light was still on and the Fire Department had an airstair nearby. The Captain shut down the engines and we ran the Evacuation checklist. I proceeded to the front door and helped the passengers out of the aircraft and down the stairs to the side of the runway where the Fire Department had set up a safe area. Buses came out within 10 minutes. We counted heads as the Passengers boarded three buses and put an Flight Attendant on each bus.

Data retrieved from NASA's ASRS site as of April 2012 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.