Medium Large Transport
Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Distraction; Confusion
Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Flight Crew Took Evasive Action; Flight Crew FLC complied w / Automation / Advisory
Chart Or Publication; Airport
We were on our descent into Durango and we had been cleared for the visual to runway 21. We left 16000 and I set in 9000 just to get a descent started. I had only been to Durango twice and both were in day VMC. I knew we were over a ridge line and because of that I didn't want to descend too quickly so I selected 1200fpm. I was basing my descent on being at roughly 8600ft on about a 5 mile final. I was keeping an eye on the terrain page and everything looked fine. We showed nothing but light green terrain. Suddenly we received a terrain warning which surprised both the captain and I as nothing had displayed on the terrain page and we were still around 12000ft. As the warning continued I slowed the rate of descent and almost immediately the warning progressed into a 'terrain pull up' call which I responded to by disconnecting the autopilot; applying full power; and climbing. At this point we observed two small red squares on the MFD. We went from perfectly normal green terrain to a pull up call in about 7 seconds. After we climbed and the warning cleared we resumed a normal approach and landing in Durango. Neither the captain or I had ever flown into the airport at night and we only had ever been there 2 or 3 times in the day so we were both a little unfamiliar. Runway 21 has no approach and the information for the airport provides no guidance whatsoever regarding what altitude we should plan to be at while making an approach to 21. It would be helpful if perhaps the company provided data saying at 10 miles we should be at 'x' altitude.
[Report Narrative Contained No Additional Information].
Flight crew reported receiving a terrain alert while descending into DRO; a high altitude airport. They responded by immediately performing an escape maneuver and; when clear of the terrain hazard; continued the descent to a normal approach and landing.