Narrative:

I was flying a 45 degree intercept to the ILS final. I was cleared a visual approach but elected to use the autoplt in coupled mode heading/south and land with automatic throttles. My position was from the northeast due to intercept at 3 mi from rinks have confidence in the autoplt to intercept. Descent rate was 1000-1500 with speed brakes and no slat or flaps at 200-210 KTS. Neither the flight director nor the autoplt did not intercept the localizer and proceeded thru localizer. I uncoupled, made a 30 degree bank back to 19R and stayed clear of 19L approach path. Still descending, though at this point I was abeam or 1/2 mi on runway side of rinks at 1200-1500 MSL and got the whoop whoop pull up, and terrain terrain, immediate advance to go around thrust and increase pitch attitude to stop descent and silence GPWS. During this approach I did not see aircraft descend below glide slope indication on pfd as soon at terrain warning stop. Neither the captain nor myself saw any terrain that should be a threat to our flight. Also in descent slats were extended and speed to 185 KTS. Fully configured with flaps and gear and stabilized on 3 degree glide slope by 800', landed in touchdown zone in normal fashion. Proper descent rate and engines spooled. As to factors affecting this approach, beside human of a rushed approach and late confign and dependency of autoflt system, or using visual perception and automation procedures concurrently, my corrective action: more airspeed confign awareness and concentrate more on one type of approach as visual or instrument coupled and more awareness of what autoplt has not done.

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Original NASA ASRS Text

Title: FO ACCOUNT OF AN UNSTABLE APCH INTO IAD THAT TRIGGERED THE GPWS.

Narrative: I WAS FLYING A 45 DEG INTERCEPT TO THE ILS FINAL. I WAS CLRED A VISUAL APCH BUT ELECTED TO USE THE AUTOPLT IN COUPLED MODE HDG/S AND LAND WITH AUTO THROTTLES. MY POSITION WAS FROM THE NE DUE TO INTERCEPT AT 3 MI FROM RINKS HAVE CONFIDENCE IN THE AUTOPLT TO INTERCEPT. DSCNT RATE WAS 1000-1500 WITH SPEED BRAKES AND NO SLAT OR FLAPS AT 200-210 KTS. NEITHER THE FLT DIRECTOR NOR THE AUTOPLT DID NOT INTERCEPT THE LOC AND PROCEEDED THRU LOC. I UNCOUPLED, MADE A 30 DEG BANK BACK TO 19R AND STAYED CLEAR OF 19L APCH PATH. STILL DESCENDING, THOUGH AT THIS POINT I WAS ABEAM OR 1/2 MI ON RWY SIDE OF RINKS AT 1200-1500 MSL AND GOT THE WHOOP WHOOP PULL UP, AND TERRAIN TERRAIN, IMMEDIATE ADVANCE TO GO AROUND THRUST AND INCREASE PITCH ATTITUDE TO STOP DSCNT AND SILENCE GPWS. DURING THIS APCH I DID NOT SEE ACFT DSND BELOW GLIDE SLOPE INDICATION ON PFD AS SOON AT TERRAIN WARNING STOP. NEITHER THE CAPT NOR MYSELF SAW ANY TERRAIN THAT SHOULD BE A THREAT TO OUR FLT. ALSO IN DSCNT SLATS WERE EXTENDED AND SPEED TO 185 KTS. FULLY CONFIGURED WITH FLAPS AND GEAR AND STABILIZED ON 3 DEG GLIDE SLOPE BY 800', LANDED IN TOUCHDOWN ZONE IN NORMAL FASHION. PROPER DSCNT RATE AND ENGINES SPOOLED. AS TO FACTORS AFFECTING THIS APCH, BESIDE HUMAN OF A RUSHED APCH AND LATE CONFIGN AND DEPENDENCY OF AUTOFLT SYSTEM, OR USING VISUAL PERCEPTION AND AUTOMATION PROCS CONCURRENTLY, MY CORRECTIVE ACTION: MORE AIRSPEED CONFIGN AWARENESS AND CONCENTRATE MORE ON ONE TYPE OF APCH AS VISUAL OR INSTRUMENT COUPLED AND MORE AWARENESS OF WHAT AUTOPLT HAS NOT DONE.

Data retrieved from NASA's ASRS site as of August 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.