Narrative:

An approach to runway 27L at ord was being flown with the autopilot on; flaps 22; in visual daylight conditions; I was pilot flying. The winds were steady at first; but during the last part of the approach (inside the marker; fully configured) they suddenly became erratic surging headwind gusts. At about 1;000 AGL; a strong; steady headwind gust was encountered; power was applied to maintain glideslope and airspeed. The pitch limit indicator appeared green; then amber; then momentarily red; setting off the stick shaker for a split second causing the autopilot to disconnect. The remaining approach was flown by hand using judicious pitch trim; and throttle inputs resulting in N1 readings between 74% and idle to try and maintain target airspeed. Target was originally reference+10; but was increased another 10;000 by the captain after the large gust. The resulting landing was on speed; on profile; and safe.there have been times in the past when I have flown approaches in wind gusts with the autopilot on; although the wind gusts were not very severe. The event in this report contained a wind gust that was just sudden and strong enough to activate the stick shaker and cause the autopilot to disconnect. After experiencing this event; I now know the point where the shaker will activate in wind gusts and will hand fly the airplane before getting into that condition.

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Original NASA ASRS Text

Title: An E-135 flight crew encountered wind shear conditions on final approach; which resulted in a momentary stick shaker. They regained control; adjusted their approach speed; and landed without further incident.

Narrative: An approach to Runway 27L at ORD was being flown with the autopilot on; flaps 22; in visual daylight conditions; I was pilot flying. The winds were steady at first; but during the last part of the approach (inside the marker; fully configured) they suddenly became erratic surging headwind gusts. At about 1;000 AGL; a strong; steady headwind gust was encountered; power was applied to maintain glideslope and airspeed. The pitch limit indicator appeared green; then amber; then momentarily red; setting off the stick shaker for a split second causing the autopilot to disconnect. The remaining approach was flown by hand using judicious pitch trim; and throttle inputs resulting in N1 readings between 74% and idle to try and maintain target airspeed. Target was originally REF+10; but was increased another 10;000 by the Captain after the large gust. The resulting landing was on speed; on profile; and safe.There have been times in the past when I have flown approaches in wind gusts with the autopilot on; although the wind gusts were not very severe. The event in this report contained a wind gust that was just sudden and strong enough to activate the stick shaker and cause the autopilot to disconnect. After experiencing this event; I now know the point where the shaker will activate in wind gusts and will hand fly the airplane before getting into that condition.

Data retrieved from NASA's ASRS site as of July 2013 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.