AT42 crew had a GPWS 'terrain, terrain' warning on approach to alb.

Attributes
ACN	518691
Time
Date	200107
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : alb.airport
State Reference	NY
Altitude	msl single value : 3200
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : alb.tracon tower : abq.tower
Operator	common carrier : air carrier
Make Model Name	ATR 42
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 2800 flight time type : 180
ASRS Report	518691
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : undershoot conflict : ground less severe other anomaly other other spatial deviation
Independent Detector	aircraft equipment : gpws other flight crewa other flight crewb
Resolutory Action	flight crew : took precautionary avoidance action flight crew : exited adverse environment
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance Aircraft FAA

Narrative:

We were in the descent into alb. Alb approach had cleared us to 2500 ft. First officer was the PF. At approximately 3200 ft, we received a GPWS 'terrain' warning. At that time, I was identing the localizer frequency for the ILS runway 1 approach. I grabbed the controls, disconnected the autoplt, and leveled off at 3000 ft. The warning continued so I began a climb while notifying ATC. At approximately 3300 ft, the warning stopped so I continued the descent to 2500 ft. After discussion with the first officer, I realized that the descent rate had been increased from 1500 FPM to 1900 FPM before the warning and after referring to the approach plate, saw that there was a 2100 ft obstacle approximately 15 NM west of the approach course. It was concluded that the altitude to which we were cleared to versus the obstacle altitude combined with the rate of descent caused the warning.

Original NASA ASRS Text

Title: AT42 CREW HAD A GPWS 'TERRAIN, TERRAIN' WARNING ON APCH TO ALB.

Narrative: WE WERE IN THE DSCNT INTO ALB. ALB APCH HAD CLRED US TO 2500 FT. FO WAS THE PF. AT APPROX 3200 FT, WE RECEIVED A GPWS 'TERRAIN' WARNING. AT THAT TIME, I WAS IDENTING THE LOC FREQ FOR THE ILS RWY 1 APCH. I GRABBED THE CTLS, DISCONNECTED THE AUTOPLT, AND LEVELED OFF AT 3000 FT. THE WARNING CONTINUED SO I BEGAN A CLB WHILE NOTIFYING ATC. AT APPROX 3300 FT, THE WARNING STOPPED SO I CONTINUED THE DSCNT TO 2500 FT. AFTER DISCUSSION WITH THE FO, I REALIZED THAT THE DSCNT RATE HAD BEEN INCREASED FROM 1500 FPM TO 1900 FPM BEFORE THE WARNING AND AFTER REFERRING TO THE APCH PLATE, SAW THAT THERE WAS A 2100 FT OBSTACLE APPROX 15 NM W OF THE APCH COURSE. IT WAS CONCLUDED THAT THE ALT TO WHICH WE WERE CLRED TO VERSUS THE OBSTACLE ALT COMBINED WITH THE RATE OF DSCNT CAUSED THE WARNING.

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.