Date: 201708
Local time of day: 1801-2400
Location: PDX.Airport, OR
Flight conditions: VMC
Light: Night
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class C PDX
ATC / advisory: TRACON P80
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying; Captain
Anomaly: Inflight Event / Encounter CFTT / CFIT
Detector: Automation Aircraft Terrain Warning; Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action; Flight Crew Became Reoriented
Contributing factors: Aircraft; Environment - Non Weather Related; Procedure
Primary problem: Environment - Non Weather Related

Narrative: On approach into PDX RWY 28R; we were cleared the visual during night/VMC conditions. ATC cleared us to descend and maintain 2;000 feet until 6 mile final or TOLOC. During the descent; approximately 5 miles south of TOLOC; the GPWS sounded 'Terrain; Terrain; Pull up; Pull up.' Captain initiated the CFIT recovery. As he initiated the escape maneuver; the GPWS warning ceased prior to Captain reaching Takeoff/Go Around (TOGA) thrust and full aft stick. I verbalized; 'TOGA thrust; Stow Speed Brakes' and verified speed brakes were stowed. The terrain and landing environment was in clear sight. During the recovery; the altitude horn sounded. Captain began a recovery to assigned altitude; descending to 2;000 feet. Aircraft momentarily descended below 2;000 feet. Almost immediately following the cessation of the GPWS warning; a traffic alert was received. ATC advised us of the traffic and reissued the altitude clearance. Landed uneventfully.


Second narrative: On visual approach to runway 28R in PDX coming from the south at 2500 feet VMC radar control with airport and runway in sight; auto-pilot on; ATC told us to descend 2000 until outer marker and cleared for visual app 28R. Captain flying initiated descent on auto-pilot and proceeded direct to outer marker. Approximately 200 knots flaps-1; 5 miles from outer marker and cross-checking glide slope indicator (announced). [At] approximately 2300 feet GPWS system calls; 'Terrain; terrain; pull-up; pull-up'. Captain initiates CFIT procedure and then quickly terminates procedure as the warning stopped and had ground environment in sight and airport and runway in sight. Then a traffic warning and an ATC call is announced for traffic. The loud altitude warning horn is heard- (initial descent was to 2000 feet but climbing and now greater than 2000 altitude deviation caused the altitude warning horn). Flight Control Unit altitude is increased to stop the horn. Captain descended towards 2000 feet for the approach. Captain momentarily descended below 2000 with traffic in sight; while aligning for runway landing. Aircraft lined up for approach 28R and uneventful landing. During post flight debrief and aircraft ground track analysis; Captain determined the spot elevation 5 miles south of TOLOC outer marker contributed to the potential CFIT trigger.


Synopsis: A320 flight crew experienced a GPWS terrain warning descending to 2000 feet 5 NM south of TOLOC during a night visual approach to PDX.