Narrative:

Roanoke tower was advised on dec/fri/96, at XA00 local that our ASOS temperature and dewpoint was not accurate. The sensor had apparently been inaccurately reporting all day. The NWS told us that it was in error and they changed our WX display to show, 'missing' for the temperature and dewpoint. They also called someone to service the ASOS. The next morning, when I reported for the day shift (five and a half hours sleep due to forced quick turnaround, but that's another story) I found that our air carrier flts could not depart because of the lack of WX information. After over an hour delay for one of the flts the air carrier obtained permission to use another WX source. The ASOS was not fixed until XH00 on dec/sat/96. Several problems: 1) the equipment operated all day, sending out inaccurate information. I understood that temperature and dewpoints are used in the forecasting models as well, therefore causing inaccurate forecasts to be generated. 2) after the technician could not be contacted, the NWS was supposed to call a backup technician for this priority outage. They did not do this. 3) the maintenance technician said that the reason for the outage was lack of maintenance due to the fact that one of the technicians bid to another job and his spot was not filled. 4) while the technician worked on the equipment, he put it back on line and allowed it to disseminate inaccurate data -- that puts us back at item #1.

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Original NASA ASRS Text

Title: CTLR SAYS ASOS WAS DISSEMINATING INACCURATE TEMP AND DEWPOINT. THE NWS PERSONNEL CHANGED IT TO READ MISSING. THIS CHANGE THEN GROUNDED ACR FLTS WHO NEEDED THE INFO. THE ACR EVENTUALLY GOT AUTH TO USE ANOTHER SOURCE FOR THE WX. THE RPTR CAME BACK ON DUTY THE NEXT DAY AND THE ASOS WAS STILL NOT FIXED, BUT DID GET REPAIRED LATER IN THE DAY.

Narrative: ROANOKE TWR WAS ADVISED ON DEC/FRI/96, AT XA00 LCL THAT OUR ASOS TEMP AND DEWPOINT WAS NOT ACCURATE. THE SENSOR HAD APPARENTLY BEEN INACCURATELY RPTING ALL DAY. THE NWS TOLD US THAT IT WAS IN ERROR AND THEY CHANGED OUR WX DISPLAY TO SHOW, 'MISSING' FOR THE TEMP AND DEWPOINT. THEY ALSO CALLED SOMEONE TO SVC THE ASOS. THE NEXT MORNING, WHEN I RPTED FOR THE DAY SHIFT (FIVE AND A HALF HRS SLEEP DUE TO FORCED QUICK TURNAROUND, BUT THAT'S ANOTHER STORY) I FOUND THAT OUR ACR FLTS COULD NOT DEPART BECAUSE OF THE LACK OF WX INFO. AFTER OVER AN HR DELAY FOR ONE OF THE FLTS THE ACR OBTAINED PERMISSION TO USE ANOTHER WX SOURCE. THE ASOS WAS NOT FIXED UNTIL XH00 ON DEC/SAT/96. SEVERAL PROBS: 1) THE EQUIP OPERATED ALL DAY, SENDING OUT INACCURATE INFO. I UNDERSTOOD THAT TEMP AND DEWPOINTS ARE USED IN THE FORECASTING MODELS AS WELL, THEREFORE CAUSING INACCURATE FORECASTS TO BE GENERATED. 2) AFTER THE TECHNICIAN COULD NOT BE CONTACTED, THE NWS WAS SUPPOSED TO CALL A BACKUP TECHNICIAN FOR THIS PRIORITY OUTAGE. THEY DID NOT DO THIS. 3) THE MAINT TECHNICIAN SAID THAT THE REASON FOR THE OUTAGE WAS LACK OF MAINT DUE TO THE FACT THAT ONE OF THE TECHNICIANS BID TO ANOTHER JOB AND HIS SPOT WAS NOT FILLED. 4) WHILE THE TECHNICIAN WORKED ON THE EQUIP, HE PUT IT BACK ON LINE AND ALLOWED IT TO DISSEMINATE INACCURATE DATA -- THAT PUTS US BACK AT ITEM #1.

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.