F100 flight crew has 2 GPWS alerts on descent, each of them false.

Attributes
ACN	334829
Time
Date	199604
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : ign
State Reference	NY
Altitude	msl bound lower : 7000 msl bound upper : 10500
Environment
Flight Conditions	IMC
Aircraft 1
Controlling Facilities	artcc : zny
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	334829
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Location: ign 250 degrees at 10 DME, descending into hpn. Descending into hpn at 9000 ft MSL we got a GPWS too low terrain warning. We accomplished the pull up maneuver, ending at approximately 10500 ft MSL. Both radar altimeters showed 1000 ft at the time of the alert. We informed ZNY of our actions and again began our descent. At approximately 7000 ft MSL the GPWS again gave a too low terrain warning with both radar altimeters showing 1000 ft. We again accomplished the pull up maneuver. Both times the GPWS alert went away on the climb. ZNY told us they had no traffic in the area that may have passed directly below us causing the alert, neither is there any terrain in the vicinity that could have set off the alert. During both alerts we were IMC.

Original NASA ASRS Text

Title: F100 FLC HAS 2 GPWS ALERTS ON DSCNT, EACH OF THEM FALSE.

Narrative: LOCATION: IGN 250 DEGS AT 10 DME, DSNDING INTO HPN. DSNDING INTO HPN AT 9000 FT MSL WE GOT A GPWS TOO LOW TERRAIN WARNING. WE ACCOMPLISHED THE PULL UP MANEUVER, ENDING AT APPROX 10500 FT MSL. BOTH RADAR ALTIMETERS SHOWED 1000 FT AT THE TIME OF THE ALERT. WE INFORMED ZNY OF OUR ACTIONS AND AGAIN BEGAN OUR DSCNT. AT APPROX 7000 FT MSL THE GPWS AGAIN GAVE A TOO LOW TERRAIN WARNING WITH BOTH RADAR ALTIMETERS SHOWING 1000 FT. WE AGAIN ACCOMPLISHED THE PULL UP MANEUVER. BOTH TIMES THE GPWS ALERT WENT AWAY ON THE CLB. ZNY TOLD US THEY HAD NO TFC IN THE AREA THAT MAY HAVE PASSED DIRECTLY BELOW US CAUSING THE ALERT, NEITHER IS THERE ANY TERRAIN IN THE VICINITY THAT COULD HAVE SET OFF THE ALERT. DURING BOTH ALERTS WE WERE IMC.

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.