Narrative:

Tdwr not capable of low level windshear advisory. Wind was 240 degrees at 40+ sustained KTS. Pilots were consistently giving reports of windshear +/-15-20 KTS and moderate turbulence by all users. 5 aircraft initiated gars due to unsafe indications with onboard equipment. Pilots were consistently asking for current wind information, which was not available due to the substandard capability of the equipment. In addition, during this period the tdwr indicated no information twice. Example '999' on the ribbon display and the big red X across the monitor with no advance warning. We have been told that this equipment is only capable of giving windshear information with WX related phenomenon. The old LLWAS we had before they installed the new tdwr is not to be turned on or used due to erroneous wind information displayed. The corrective action would be to install the tdwr network expansion which is what the 7110.65J refers to. This system has an integrated ('LLWAS III') which is capable of providing microburst, windshear and wind information oriented to the threshold or departure end of a runway. Callback conversation with reporter revealed the following information: reporter stated the tdwr unit is a ctrfield wind unit which uses wind average for reporting the wind. Reporter stated the LLWAS sensors located in 4 quadrants, approach and departure of the runways, plus ctrfield have been removed. Reporter indicated the tdwr works with precipitation and should alarm when a microburst occurs. Reporter stated reporter has not heard the alarm except when the technicians are testing the system. Reporter indicated that pilots will take evasive action when aircraft instruments indicate a windshear is detected.

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Original NASA ASRS Text

Title: TDWR WIND EQUIP NOT CAPABLE OF LOW WINDSHEAR ADVISORIES. RPTR CLAIMS PLTS WERE GIVING RPTS OF WINDSHEAR + OR - 15- 20 KTS. EQUIP INDICATED NO INFO TWICE. RPTED THAT TDWR IS ONLY CAPABLE OF WINDSHEAR INFO WITH WX RELATED PHENOMENON.

Narrative: TDWR NOT CAPABLE OF LOW LEVEL WINDSHEAR ADVISORY. WIND WAS 240 DEGS AT 40+ SUSTAINED KTS. PLTS WERE CONSISTENTLY GIVING RPTS OF WINDSHEAR +/-15-20 KTS AND MODERATE TURB BY ALL USERS. 5 ACFT INITIATED GARS DUE TO UNSAFE INDICATIONS WITH ONBOARD EQUIP. PLTS WERE CONSISTENTLY ASKING FOR CURRENT WIND INFO, WHICH WAS NOT AVAILABLE DUE TO THE SUBSTANDARD CAPABILITY OF THE EQUIP. IN ADDITION, DURING THIS PERIOD THE TDWR INDICATED NO INFO TWICE. EXAMPLE '999' ON THE RIBBON DISPLAY AND THE BIG RED X ACROSS THE MONITOR WITH NO ADVANCE WARNING. WE HAVE BEEN TOLD THAT THIS EQUIP IS ONLY CAPABLE OF GIVING WINDSHEAR INFO WITH WX RELATED PHENOMENON. THE OLD LLWAS WE HAD BEFORE THEY INSTALLED THE NEW TDWR IS NOT TO BE TURNED ON OR USED DUE TO ERRONEOUS WIND INFO DISPLAYED. THE CORRECTIVE ACTION WOULD BE TO INSTALL THE TDWR NETWORK EXPANSION WHICH IS WHAT THE 7110.65J REFERS TO. THIS SYS HAS AN INTEGRATED ('LLWAS III') WHICH IS CAPABLE OF PROVIDING MICROBURST, WINDSHEAR AND WIND INFO ORIENTED TO THE THRESHOLD OR DEP END OF A RWY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE TDWR UNIT IS A CTRFIELD WIND UNIT WHICH USES WIND AVERAGE FOR RPTING THE WIND. RPTR STATED THE LLWAS SENSORS LOCATED IN 4 QUADRANTS, APCH AND DEP OF THE RWYS, PLUS CTRFIELD HAVE BEEN REMOVED. RPTR INDICATED THE TDWR WORKS WITH PRECIPITATION AND SHOULD ALARM WHEN A MICROBURST OCCURS. RPTR STATED RPTR HAS NOT HEARD THE ALARM EXCEPT WHEN THE TECHNICIANS ARE TESTING THE SYS. RPTR INDICATED THAT PLTS WILL TAKE EVASIVE ACTION WHEN ACFT INSTS INDICATE A WINDSHEAR IS DETECTED.

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.