Date: 201912
Local time of day: 1801-2400
Location: CHA.Airport, TN
Flight conditions: VMC
Light: Night
Aircraft: Medium Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class C CHA
ATC / advisory: TRACON CHA; Tower CHA
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: Captain; Pilot Not Flying
Anomaly: Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Detector: Automation Aircraft Terrain Warning; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew FLC Overrode Automation; Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure; Environment - Non Weather Related
Primary problem: Human Factors

Narrative: I was acting as Pilot Flying on flight. CHA was VFR when we checked on with Chattanooga Approach we were told to expect visual approach to Runway 2. Approach instructed us to descend to 3;600 feet and vectored us to enter a left downwind to Runway 2. The weather was VMC and visibility was good. We were visual with the surrounding terrain and lighted obstacles. I also had the terrain radar displayed on the MFD for additional situational awareness. Once we reported CHA in sight when we were abeam the airport on the left downwind; Approach Control cleared us for the visual approach for Runway 2 and told us to contact the Tower. Tower cleared us to land Runway 2. Approximately abeam MORTT; the FAF for ILS 2; 2;500 feet was dialed into the altitude selector and we began our descent in order to cross MORTT at 2;500 feet. Just as I was reaching for the heading knob on the FCP to start our base turn the GPWS 'Terrain; Terrain' aural alert sounded. I immediately executed a climb to clear the conflict and the Captain informed Tower. As we requested to be vectored for the ILS; Tower handed us to Approach Control and we climbed to 4;000 feet. As we were still on a downwind heading; Approach Control; vectored us onto the final approach course for the ILS and cleared us for the ILS. We then landed in CHA without further incident.Suggestions: In the future when operating in an environment such as CHA during a visual approach; it would probably be best to coordinate with ATC to extend downwind and not to start the decent until turning base or until established on the final approach course.


Second narrative: On the left downwind for Runway 2 into CHA; cleared for the visual approach to Runway 2 within 10 miles of the airport. Descended out of 3;600 feet for 2;500 feet when we received a GPWS alert with a Pull Up. Thought maybe it was a false alert; queried ATC and discovered we exceeded descent parameters or the VS rate gave the aircraft the illusion we were too clear to the terrain. The alert happened around 3;000 feet. We were clear of all obstacles and terrain. I told the flying pilot to add power and pitch up climb to 4;000 feet. We were extended in the downwind and re-vectored back on the approach and landed on Runway 2 with no further occurrences.Use a lower descent rate; possibly wait until established on the approach; or start the descent closer to the base leg.


Synopsis: Air carrier flight crew reported a CFTT incident during visual approach to CHA airport.