Windshear. Go around.

Attributes
ACN	320700
Time
Date	199511
Day	Sat
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : lga
State Reference	NY
Altitude	msl bound lower : 800 msl bound upper : 1000
Environment
Flight Conditions	Marginal
Light	Night
Aircraft 1
Controlling Facilities	tower : lga
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 16000 flight time type : 1500
ASRS Report	320700
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 6500 flight time type : 400
ASRS Report	320693
Events
Anomaly	inflight encounter : weather other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

During approach (ILS DME runway 13 lga) between 1000-800 ft MSL, the 'windshear' visual (ADI) and aural warnings went off. Winds were gusty, with some moderate turbulence, but approach was stable. Landing check had been completed. Surface winds were 150-170 degrees at 24 KTS, gusting to 33 KTS. Airspeed fluctuations were no more than plus or minus 10 KTS. As per company procedure, a go around was initiated. Between 1500-2000 ft MSL, airspeed began fluctuating plus or minus 15 KTS or more and a brief stick shaker was heard. Aircraft had not been cleaned up at this point, as per windshear technique. About 2000 ft aircraft began descending and vsi went to 1000-1200 FPM down. Airspeed then increased immediately 40 KTS in an 'increasing' type of windshear. At 1600 ft MSL vsi was increased to a climbing rate 1000 FPM and the airspeed stabilized. After flying out of windshear aircraft was cleaned up and go around was continued. We reported windshear to tower during our go around, but no other aircraft reported this windshear. Subsequent approach and landing, albeit turbulent, was stable and uneventful. No further windshear warnings occurred. I believe the windshear detection, alert, and guidance system on our aircraft was giving us a warning that might otherwise been discovered too late.

Original NASA ASRS Text

Title: WINDSHEAR. GAR.

Narrative: DURING APCH (ILS DME RWY 13 LGA) BTWN 1000-800 FT MSL, THE 'WINDSHEAR' VISUAL (ADI) AND AURAL WARNINGS WENT OFF. WINDS WERE GUSTY, WITH SOME MODERATE TURB, BUT APCH WAS STABLE. LNDG CHK HAD BEEN COMPLETED. SURFACE WINDS WERE 150-170 DEGS AT 24 KTS, GUSTING TO 33 KTS. AIRSPD FLUCTUATIONS WERE NO MORE THAN PLUS OR MINUS 10 KTS. AS PER COMPANY PROC, A GAR WAS INITIATED. BTWN 1500-2000 FT MSL, AIRSPD BEGAN FLUCTUATING PLUS OR MINUS 15 KTS OR MORE AND A BRIEF STICK SHAKER WAS HEARD. ACFT HAD NOT BEEN CLEANED UP AT THIS POINT, AS PER WINDSHEAR TECHNIQUE. ABOUT 2000 FT ACFT BEGAN DSNDING AND VSI WENT TO 1000-1200 FPM DOWN. AIRSPD THEN INCREASED IMMEDIATELY 40 KTS IN AN 'INCREASING' TYPE OF WINDSHEAR. AT 1600 FT MSL VSI WAS INCREASED TO A CLBING RATE 1000 FPM AND THE AIRSPD STABILIZED. AFTER FLYING OUT OF WINDSHEAR ACFT WAS CLEANED UP AND GAR WAS CONTINUED. WE RPTED WINDSHEAR TO TWR DURING OUR GAR, BUT NO OTHER ACFT RPTED THIS WINDSHEAR. SUBSEQUENT APCH AND LNDG, ALBEIT TURBULENT, WAS STABLE AND UNEVENTFUL. NO FURTHER WINDSHEAR WARNINGS OCCURRED. I BELIEVE THE WINDSHEAR DETECTION, ALERT, AND GUIDANCE SYS ON OUR ACFT WAS GIVING US A WARNING THAT MIGHT OTHERWISE BEEN DISCOVERED TOO LATE.

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.