Narrative:

Approximately 3 mi out on final approach, my first officer called out '1 DOT low' on the GS. Subsequently, we had a full deflection on the GS and 3/4 on the localizer followed by a 20 KT loss of airspeed. Power was added, a leveloff was executed and a right correction recaptured the localizer. The following approach and landing was uneventful. Subsequently, I now believe I encountered windshear. The quality of my performance was affected because I did not immediately recognize the deteriorating situation or the severity of this condition. I believe this was due to: 1) the initial onset was very subtle. 2) the lack of convective activity in the area. 3) relatively smooth air. 4) the lack of any windshear reports.

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Original NASA ASRS Text

Title: LACK OF AGGRESSIVE CORRECTION WITH POSSIBLE WINDSHEAR CAUSES DC9 FLC TO LEVEL OFF AND RECAPTURE GS AND LOC AT ATL, GA.

Narrative: APPROX 3 MI OUT ON FINAL APCH, MY FO CALLED OUT '1 DOT LOW' ON THE GS. SUBSEQUENTLY, WE HAD A FULL DEFLECTION ON THE GS AND 3/4 ON THE LOC FOLLOWED BY A 20 KT LOSS OF AIRSPD. PWR WAS ADDED, A LEVELOFF WAS EXECUTED AND A R CORRECTION RECAPTURED THE LOC. THE FOLLOWING APCH AND LNDG WAS UNEVENTFUL. SUBSEQUENTLY, I NOW BELIEVE I ENCOUNTERED WINDSHEAR. THE QUALITY OF MY PERFORMANCE WAS AFFECTED BECAUSE I DID NOT IMMEDIATELY RECOGNIZE THE DETERIORATING SIT OR THE SEVERITY OF THIS CONDITION. I BELIEVE THIS WAS DUE TO: 1) THE INITIAL ONSET WAS VERY SUBTLE. 2) THE LACK OF CONVECTIVE ACTIVITY IN THE AREA. 3) RELATIVELY SMOOTH AIR. 4) THE LACK OF ANY WINDSHEAR RPTS.

Data retrieved from NASA's ASRS site as of July 2007 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.