Date: 201710
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class E ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Anomaly: Inflight Event / Encounter CFTT / CFIT
Detector: Automation Aircraft Terrain Warning; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Executed Go Around / Missed Approach; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Contributing factors: Airspace Structure; Environment - Non Weather Related
Primary problem: Environment - Non Weather Related

Narrative: Upon on receiving our Arrival ATIS; we realized that runway XXR would be in use. As there was nothing in the FMS to extract and this was both of our first times going into [the runway]; First Officer (FO) decided to build an extended centerline from Runway. In addition; we also built in 3; 6; and 9 DME waypoints on the extended centerline for situational awareness and descent planning. We also briefed the plan of arrival as there is a mountain on the approach path with the highest obstacle being 6136ft. Somewhere between Waypoint ZZZZZ; we were given a SSE heading and descent down to 7500 ft. On this heading; we were asked if we had the runway in sight. It was day VFR and we both confirmed [the] airport as well as Runway. We were cleared for the Visual Approach at this point. Referencing our altitudes on the DME waypoints we inserted into the FMS; we began a gradual descent and started configuring for the approach. As we proceeded inbound; we stayed vigilant about the terrain on the approach that we had talked about earlier.  As we got closer to the terrain on the approach; we got an obstacle alert. We were Day VFR and could see the obstacles (cell towers on the top of the mountain). Both these towers were to the north and south of our path; and we had visual contact with them; we continued the approach. We then received a second Obstacle alert shortly after. At this point; FO; disconnected the Autopilot and reduced the Rate of Descent and pretty much leveled off. We were both visually scanning for any terrain in front of us. Approximately 5-10 secs later; we received a GPWS 'Pull Up' warning. Though it was Day VFR; we immediately complied with the warning; thrust levers were advanced to Max detent (total duration 15-20secs); while I scanned below for terrain. Notified ATC and we were given level off at 8000ft. In the climb; we retracted gear and flaps on schedule. (No speed limitations exceeded). We were told that we would be vectored for another approach to [the runway]. I made a brief PA advising the Passengers that we would be returning for another landing. We were given a right downwind to base for [the runway] and carried out the second approach without incident. Once at the gate; a call was made to Dispatch explaining the issue; and then to Maintenance; where a logbook entry for the thrust levers being advanced to Max detent was logged. In conclusion; we believe that the GPWS warning might have been triggered by the cell phone towers on the top of the mountain. Also; both FO and me had Terrain on our respective MFDs and at no point do any of us recall seeing a terrain red along our flight path. There was some yellow contours due to the rising ridge line north of us. Airing on the side of caution and keeping safety in mind; there was no question about it; we utilized a GPWS escape maneuver and opted to try again. So the FO and I have discussed this particular scenario in great detail after it occurred. We are not sure if we were one of the first ones to get this approach from the West. This was my first time getting this runway for landing as well. This particular combination posed to be a high threat in my opinion. Some guidance on this would serve the entire pilot community of Compass as it definitely has the potential to cause future issues as well. There is no approach that is extractable and so this approach has to be tailor made. We watched many other airplanes take the same approach path we took but are not sure if they stayed high and dove down after the ridge. We would certainly be interested in hearing what the best approach strategy would be for this runway and from a westerly direction of flight.




Synopsis: The Captain of an Embraer 175 reported going around after receiving a GPWS warning to pull-up during initial approach.