Date: 201304
Local time of day: 0601-1200
Location: CHA.Airport, TN
Flight conditions: VMC
Light: Dawn
Aircraft: B757-200
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class C CHA
ATC / advisory: TRACON CHA
Aircraft component: GPWS
Component problem: Design
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe
Detector: Automation Aircraft Terrain Warning
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; Flight Crew Took Evasive Action
Contributing factors: Aircraft; Airport; Human Factors
Primary problem: Aircraft

Narrative: While on visual approach to Runway 20 CHA; approximately 2-3 miles from HIXON FAF while leveling at 2;100 FT crossing altitude; received EGPWS pull up warning. As pilot flying I immediately disconnected the autopilot; raised the nose and began to advance the throttles when the warning ceased. Both I and the First Officer had terrain selected on Nav display and rate of descent did not seem excessive. Airspeed was approximately 175 while slowing to 170. High terrain in area to west was behind aircraft. Light conditions were good as it was right at dawn and visibility was clear. I could see the airport. After the warning ceased we intercepted the localizer just prior to HIXON; slightly high; but able to continue normal visual approach and landing. I believe the conditions were 'day VFR' and the warning was in error. Occurrence was debriefed between myself and the First Officer and both of us thought it was a normal approach. Logbook entry made and Maintenance debriefed. I could have asked for vectors to final and accepted the visual later or possibly slowed the rate of descent prior to HIXON.


Second narrative: Aircraft was maneuvering for a visual approach; backed up with the ILS to Runway 20 at CHA in clear VMC conditions. Pilot flying (Captain) had turned approximately 5 NM right base leg approximately 1-2 NM west of HIXON (FAF) leveled at 2;100 FT MSL (published crossing altitude). Aircraft was slowing to approximately 170 KIAS in ALT HOLD with the autopilot engaged to intercept the localizer when we received a GPWS TERRAIN Warning. Pilot flying immediately initiated the escape maneuver. As soon as thrust levers were advanced the Warning stopped. No engine limitations were exceeded. Terrain display was selected on both pilot's displays and no terrain conflicts were noted at any time during the approach or escape man. Seeing no terrain (VMC) and suspecting it to be a GPWS anomaly we elected to continue the visual approach with no further issues. GPWS system was written up in the logbook as suspected anomaly. Adhere to published altitudes to ensure terrain clearance; visually clear the flight path in VMC; and maintain positional terrain clearance while maneuvering for a visual approach in mountainous areas.


Synopsis: B757-200 flight crew experiences an EGPWS terrain warning turning right base for Runway 20 at CHA and leveling at 2;100 FT. At the first addition of thrust the warning ceases and the approach is continued to landing. Day light VMC prevailed at the time.