Air carrier crew has false terrain warning near cvg.

Attributes
ACN	459527
Time
Date	200001
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : cvg.airport
State Reference	KY
Altitude	msl bound lower : 7000 msl bound upper : 9000
Environment
Flight Conditions	IMC
Weather Elements	Rain
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	459527
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe inflight encounter : weather other anomaly other
Independent Detector	aircraft equipment : gpws other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Supplementary
Problem Areas	Aircraft Weather
Primary Problem	Aircraft

Narrative:

Approximately 20 mi nne of cvg, first officer leg. On arrival into cvg, being vectored from the north and dodging WX. Level at 7000 ft, while briefing and setting up the approach, we encountered moderate precipitation. Radio altimeter flashed on my pfd showing various altitudes below 500 ft. Within a few seconds we received a GPWS warning of terrain. We were in the dark and in rain. First officer applied the escape/climb procedure and I notified ATC. I think the controller misunderstood me and thought we were maneuvering for an RA. At any rate, we leveled at 9000 ft and were told to maintain that altitude and were then vectored for an ILS to cvg. I believe the GPWS warning was the result of the precipitation and was a nuisance warning. The system worked normally throughout the remainder of the flight and landing.

Original NASA ASRS Text

Title: ACR CREW HAS FALSE TERRAIN WARNING NEAR CVG.

Narrative: APPROX 20 MI NNE OF CVG, FO LEG. ON ARR INTO CVG, BEING VECTORED FROM THE N AND DODGING WX. LEVEL AT 7000 FT, WHILE BRIEFING AND SETTING UP THE APCH, WE ENCOUNTERED MODERATE PRECIP. RADIO ALTIMETER FLASHED ON MY PFD SHOWING VARIOUS ALTS BELOW 500 FT. WITHIN A FEW SECONDS WE RECEIVED A GPWS WARNING OF TERRAIN. WE WERE IN THE DARK AND IN RAIN. FO APPLIED THE ESCAPE/CLB PROC AND I NOTIFIED ATC. I THINK THE CTLR MISUNDERSTOOD ME AND THOUGHT WE WERE MANEUVERING FOR AN RA. AT ANY RATE, WE LEVELED AT 9000 FT AND WERE TOLD TO MAINTAIN THAT ALT AND WERE THEN VECTORED FOR AN ILS TO CVG. I BELIEVE THE GPWS WARNING WAS THE RESULT OF THE PRECIP AND WAS A NUISANCE WARNING. THE SYS WORKED NORMALLY THROUGHOUT THE REMAINDER OF THE FLT AND LNDG.

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.