Narrative:

During arrival to bzn we were left high by ATC and were directed to look for preceding traffic. We found the traffic and were then cleared for a visual approach to runway 12 behind that traffic. I told tower that we would need to make a turn or some s-turns to get down and they approved them. Being high; the captain (flying pilot) decided to cross the final and make a left 270 degree turn back onto final. During this descent the captain was descending at a rather high rate (about 2;000 FPM) with flaps 5 and gear down just under 200 KTS. We were just north of the fix manni with a west or southwest heading; during the 270 degree turn; when we got down to the altitude of the glideslope (about 7;000 MSL). Since the captain was still descending rather steep; I told the captain that we were about on the glideslope now. The captain agreed. The captain continued to descend a bit below the glideslope. I figured that the captain was attempting to descend to near a pattern altitude; and in later talks with the captain it sounds as if that was the intension; however with the high descent rate and higher terrain in that area we received a terrain caution that almost immediately changed to a pull up warning. The captain proceeded to climb and follow the GPWS procedure. The warning quickly went away and the captain decided to proceed with the approach as we were nearly on final and the glideslope now. I suspect that if the descent rate had not been as high we would not have got any cautions or warnings since we were still around 6;500 MSL and never any lower than about 1;500 AGL (about 1;600 ft is the lowest we noticed on the RA). Looking back; as the pilot not flying; I wish that I would have said something more about descending to that altitude that far out with such a high descent rate. We were; after all; already down to the glideslope and the terrain is higher in that area. However; at the time I didn't expect that it was a high enough descent rate that high above the ground to set off the GPWS alerts and I expected that the captain just wanted to get to near a traffic pattern altitude before slowing further.

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Original NASA ASRS Text

Title: An aircraft approaching BZN activated its GPWS because the aircraft arrived high on profile and the Captain flew a wide descending turn at about 2;000 FPM down to 1;600 FT in order to regained the ILS.

Narrative: During arrival to BZN we were left high by ATC and were directed to look for preceding traffic. We found the traffic and were then cleared for a visual approach to Runway 12 behind that traffic. I told Tower that we would need to make a turn or some S-turns to get down and they approved them. Being high; the Captain (flying pilot) decided to cross the final and make a left 270 degree turn back onto final. During this descent the Captain was descending at a rather high rate (about 2;000 FPM) with flaps 5 and gear down just under 200 KTS. We were just north of the fix MANNI with a west or southwest heading; during the 270 degree turn; when we got down to the altitude of the glideslope (about 7;000 MSL). Since the Captain was still descending rather steep; I told the Captain that we were about on the glideslope now. The Captain agreed. The Captain continued to descend a bit below the glideslope. I figured that the Captain was attempting to descend to near a pattern altitude; and in later talks with the Captain it sounds as if that was the intension; however with the high descent rate and higher terrain in that area we received a terrain caution that almost immediately changed to a pull up warning. The Captain proceeded to climb and follow the GPWS procedure. The warning quickly went away and the Captain decided to proceed with the approach as we were nearly on final and the glideslope now. I suspect that if the descent rate had not been as high we would not have got any cautions or warnings since we were still around 6;500 MSL and never any lower than about 1;500 AGL (about 1;600 FT is the lowest we noticed on the RA). Looking back; as the pilot not flying; I wish that I would have said something more about descending to that altitude that far out with such a high descent rate. We were; after all; already down to the glideslope and the terrain is higher in that area. However; at the time I didn't expect that it was a high enough descent rate that high above the ground to set off the GPWS alerts and I expected that the Captain just wanted to get to near a traffic pattern altitude before slowing further.

Data retrieved from NASA's ASRS site as of April 2012 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.