Narrative:

On approach into denver; ATC was forecasting gusty winds and windshear alerts. To compensate for the inclement weather conditions I briefed the captain that I would fly an additional 5 knots on approach. We also reviewed and briefed the callouts in case a go-around became necessary. We were about 1;000 feet above the runway; fully configured and stable when the aircraft entered a pretty strong downdraft. To stay on glideslope and keep the airspeed from degrading; I ended up increasing N1 thrust to well over 80%. Even with this thrust; the aircraft was merely holding airspeed on the glideslope. I knew that there would be a backside to the downdraft and was prepared for a rapid increase in performance. My plan was to reduce the thrust the minute I felt the plane picking up speed and/or getting high on the glideslope. We bounced pretty sharply as the wind shifted; accompanied by a fleeting application of the stick shaker. I knew it was turbulence-related because my speed was fine. In fact; when I looked at my airspeed indicator we were above approach speed and accelerating fast! In addition; we began to get high on the glideslope. Recognizing the 'backside' of the downdraft I reduced thrust to about 60% and began to correct the approach path. '500 to go; correcting everything;' I said. 'Roger; cleared to land 34R;' captain said. The aircraft was stable by 400 feet and the landing was uneventful. Upon landing and turning off the runway we saw the aircraft behind us go-around as well as an aircraft on 35L. During the entire event no windshear alerts or warnings were received. Root cause was the inclement wind conditions resulting in a degradation of performance followed by a rapid increase in performance. Contributing factors include an overconfidence in ability (at no point did I think a continued landing was unsafe); also I was so focused on controlling the airspeed and glideslope I ignored the brief shaker activation as a turbulence-related anomaly. Mentally; I knew that our speed was increasing as we entered the backside of the downdraft and rather than increase thrust for a go-around I decreased it to maintain a stabilized approach. It was a split-second decision; and one that I didn't even regret until I had time to think about it later. In the future; I hope to have the discipline to go-around immediately if I feel the stick-shaker; even if it is turbulence-related. In addition; good judgment must be used when making the 500 foot stable continue call. Everyone has an approach every now and then with one parameter out of whack at 500 feet (whether it's airspeed; glideslope; etc.) but when you have to say '500 feet to go; correcting everything;' maybe it's time to go around and try it again!!

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Original NASA ASRS Text

Title: CRJ-200 First Officer reports continuing an approach after passing through a microburst resulting in large power adjustments and a momentary stick shaker. The approach is not stable at 500 feet but is continued to landing. Several go-arounds occur after this landing.

Narrative: On approach into Denver; ATC was forecasting gusty winds and windshear alerts. To compensate for the inclement weather conditions I briefed the Captain that I would fly an additional 5 knots on approach. We also reviewed and briefed the callouts in case a go-around became necessary. We were about 1;000 feet above the runway; fully configured and stable when the aircraft entered a pretty strong downdraft. To stay on glideslope and keep the airspeed from degrading; I ended up increasing N1 thrust to well over 80%. Even with this thrust; the aircraft was merely holding airspeed on the glideslope. I knew that there would be a backside to the downdraft and was prepared for a rapid increase in performance. My plan was to reduce the thrust the minute I felt the plane picking up speed and/or getting high on the glideslope. We bounced pretty sharply as the wind shifted; accompanied by a fleeting application of the stick shaker. I knew it was turbulence-related because my speed was fine. In fact; when I looked at my airspeed indicator we were above approach speed and accelerating fast! In addition; we began to get high on the glideslope. Recognizing the 'backside' of the downdraft I reduced thrust to about 60% and began to correct the approach path. '500 to go; correcting everything;' I said. 'Roger; cleared to land 34R;' Captain said. The aircraft was stable by 400 feet and the landing was uneventful. Upon landing and turning off the runway we saw the aircraft behind us go-around as well as an aircraft on 35L. During the entire event no windshear alerts or warnings were received. Root cause was the inclement wind conditions resulting in a degradation of performance followed by a rapid increase in performance. Contributing factors include an overconfidence in ability (at no point did I think a continued landing was unsafe); also I was so focused on controlling the airspeed and glideslope I ignored the brief shaker activation as a turbulence-related anomaly. Mentally; I knew that our speed was increasing as we entered the backside of the downdraft and rather than increase thrust for a go-around I decreased it to maintain a stabilized approach. It was a split-second decision; and one that I didn't even regret until I had time to think about it later. In the future; I hope to have the discipline to go-around immediately if I feel the stick-shaker; even if it is turbulence-related. In addition; good judgment must be used when making the 500 foot stable continue call. Everyone has an approach every now and then with one parameter out of whack at 500 feet (whether it's airspeed; glideslope; etc.) but when you have to say '500 feet to go; correcting everything;' maybe it's time to go around and try it again!!

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.