Narrative:

While descending into sna; we were cleared to 6300 feet and to call the airport. Captain called the airport in sight so I told ATC and we were immediately cleared for the visual approach. At this point; we had already cleaned up the flight plan and extended final. We were at flaps configuration 2; in an open descent and captain set 2;200 feet; the FAF altitude; and armed the approach. I was watching the radar altimeter fluctuate wildly (normally) as we crossed the mountains east of sna. It rapidly started approaching 2;000 feet and I was just about to mention it when the 'terrain; terrain; pull up; pull up' warning sounded. The captain reacted immediately although not strongly since it was simply not warranted by disconnecting the autopilot and reducing the descent rate. We both saw the terrain and I saw the RA hit 1;600 feet at the closest. I pointed out the airspeed decreasing below the selected airspeed to the captain (open descent; above selected altitude) and after a few moments of hesitation; he selected vertical speed (vs) and put the airplane back into a speed mode and we recovered full situational awareness and both of us were back in the green. During the yellow distractions; the captain was drifting off heading. I saw this but chose to first; help us get back to the green in regards to the airspeed. Once that was done; the captain corrected back to the final intercept heading and completed the approach with no further interruptions. Cause [was an] excessive descent rate over the last edge of the mountains. Suggestions: delay descent; when possible; until after terrain.

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Original NASA ASRS Text

Title: A319 First Officer reported receiving a GPWS terrain warning on descent into SNA that was probably related to high closure rate.

Narrative: While descending into SNA; we were cleared to 6300 feet and to call the airport. Captain called the airport in sight so I told ATC and we were immediately cleared for the visual approach. At this point; we had already cleaned up the flight plan and extended final. We were at flaps configuration 2; in an open descent and Captain set 2;200 feet; the FAF altitude; and armed the approach. I was watching the radar altimeter fluctuate wildly (normally) as we crossed the mountains east of SNA. It rapidly started approaching 2;000 feet and I was just about to mention it when the 'Terrain; Terrain; Pull up; Pull up' warning sounded. The Captain reacted immediately although not strongly since it was simply not warranted by disconnecting the autopilot and reducing the descent rate. We both saw the terrain and I saw the RA hit 1;600 feet at the closest. I pointed out the airspeed decreasing below the selected airspeed to the Captain (open descent; above selected altitude) and after a few moments of hesitation; he selected Vertical Speed (VS) and put the airplane back into a speed mode and we recovered full situational awareness and both of us were back in the green. During the yellow distractions; the Captain was drifting off heading. I saw this but chose to first; help us get back to the green in regards to the airspeed. Once that was done; the Captain corrected back to the final intercept heading and completed the approach with no further interruptions. Cause [was an] excessive descent rate over the last edge of the mountains. Suggestions: Delay descent; when possible; until after terrain.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.