Narrative:

While on the ground at hts, we received the ATIS. At the time, nothing seemed too unusual, but then we were not looking to find anything unusual. ATIS reported 1/4 mi visibility temperature of 14 degrees, dewpoint 1 degree with haze. It was obvious fog consumed area, but as far as we were concerned, we were legal for takeoff. After takeoff, we really analyzed the ATIS. With fog in the area, and a temperature dewpoint spread of 14/1 with haze, something seemed wrong. We came to find out later the WX equipment malfunctioned. For takeoff at the time, this did not cross our mind. Sometimes I feel we put too much importance on machines giving correct information. This was our error. Supplemental information from acn 593495: we were the first flight of the day scheduled. The tower was open. Several days later, we became aware that a few of our airline's crews took off and landed with the ATIS/WX at hts notamed either inoperative or inaccurate on the same day we departed. Neither I nor the captain knows if the ATIS/WX was notamed inoperative or inaccurate at our time of departure. NOTAMS are often hastily checked or overlooked in the dispatch paperwork.

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Original NASA ASRS Text

Title: CL-65 CREW QUESTIONS TKOF LEGALITY WITH LOW VISIBILITY RECORDED ON ATIS. LATER, THE CREW FOUND A NOTAM OF INACCURATE WX MEASURING TOOLS AT THE ARPT.

Narrative: WHILE ON THE GND AT HTS, WE RECEIVED THE ATIS. AT THE TIME, NOTHING SEEMED TOO UNUSUAL, BUT THEN WE WERE NOT LOOKING TO FIND ANYTHING UNUSUAL. ATIS RPTED 1/4 MI VISIBILITY TEMP OF 14 DEGS, DEWPOINT 1 DEG WITH HAZE. IT WAS OBVIOUS FOG CONSUMED AREA, BUT AS FAR AS WE WERE CONCERNED, WE WERE LEGAL FOR TKOF. AFTER TKOF, WE REALLY ANALYZED THE ATIS. WITH FOG IN THE AREA, AND A TEMP DEWPOINT SPREAD OF 14/1 WITH HAZE, SOMETHING SEEMED WRONG. WE CAME TO FIND OUT LATER THE WX EQUIP MALFUNCTIONED. FOR TKOF AT THE TIME, THIS DID NOT CROSS OUR MIND. SOMETIMES I FEEL WE PUT TOO MUCH IMPORTANCE ON MACHINES GIVING CORRECT INFO. THIS WAS OUR ERROR. SUPPLEMENTAL INFO FROM ACN 593495: WE WERE THE FIRST FLT OF THE DAY SCHEDULED. THE TWR WAS OPEN. SEVERAL DAYS LATER, WE BECAME AWARE THAT A FEW OF OUR AIRLINE'S CREWS TOOK OFF AND LANDED WITH THE ATIS/WX AT HTS NOTAMED EITHER INOP OR INACCURATE ON THE SAME DAY WE DEPARTED. NEITHER I NOR THE CAPT KNOWS IF THE ATIS/WX WAS NOTAMED INOP OR INACCURATE AT OUR TIME OF DEP. NOTAMS ARE OFTEN HASTILY CHKED OR OVERLOOKED IN THE DISPATCH PAPERWORK.

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.