Narrative:

On right downwind, south and east of swf, in the vicinity of cliffs on the hudson river and in IMC conditions, we received a ground proximity 'whoop whoop - pull up' warning. I immediately climbed from 3000 to 5000'. Informed ATC who said descend to 2600' on same heading. We were given 2 right turns and handed via ILS on runway 09. Supplemental information from acn 161005: straight and level flight at 3000' MSL, about 8 mi south and west of field, aircraft GPWS output was, 'whoop-whoop, pull up.' captain followed company procedures for pull-up, while I told ATC about the altitude change to 500' MSL. Rest of flight uneventful.

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Original NASA ASRS Text

Title: ON VECTORS TO SWF, ACR MLG EXPERIENCES ACTIVATED GND PROX WARNING.

Narrative: ON RIGHT DOWNWIND, S AND E OF SWF, IN THE VICINITY OF CLIFFS ON THE HUDSON RIVER AND IN IMC CONDITIONS, WE RECEIVED A GND PROX 'WHOOP WHOOP - PULL UP' WARNING. I IMMEDIATELY CLBED FROM 3000 TO 5000'. INFORMED ATC WHO SAID DSND TO 2600' ON SAME HDG. WE WERE GIVEN 2 RIGHT TURNS AND HANDED VIA ILS ON RWY 09. SUPPLEMENTAL INFO FROM ACN 161005: STRAIGHT AND LEVEL FLT AT 3000' MSL, ABOUT 8 MI S AND W OF FIELD, ACFT GPWS OUTPUT WAS, 'WHOOP-WHOOP, PULL UP.' CAPT FOLLOWED COMPANY PROCS FOR PULL-UP, WHILE I TOLD ATC ABOUT THE ALT CHANGE TO 500' MSL. REST OF FLT UNEVENTFUL.

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.