Narrative:

I am a WX observer whose job is to augment the ASOS (automated surface observing system) whenever I deem necessary. This must be done nearly constantly in order to accurately reflect current WX conditions. In writing this, I am not just citing one particular incident, but rather, I am describing my 2 1/2 yrs experience with ASOS and my opinion of it. I truly feel that without augmentation and backup the ASOS is unsafe for air traffic. In my opinion, the system was designed to fail. For instance, its ceilometer only sees clouds directly over its sensor. This means on a dreary overcast day, if there is one small break in the clouds over the sensor, it calls the sky clear. Furthermore, the visibility sensors are almost always inaccurate. They generally show the visibility to be much greater than it actually is. Both the ceiling and visibility are obviously important factors to the safety of air traffic. This is all not even to mention how much WX phenomena the ASOS can't even detect: tornadic activity, thunderstorms and lightning, hail, ice pellets, virga, etc. Another problem with ASOS is its constant need of repair. It would actually be a rare event in which ASOS is fully functional. For example, at this site right now there are 2 items in need of service, both of which have been out for over 2 weeks. Our office used to keep a log where every time an observer had to augment ASOS' report of WX conditions, we made an entry. We no longer keep this log because it is a practically impossible and overwhelming task. I do not have to imagine how inaccurately ASOS reports WX on its own, I see it every day. Anyone who does not recognize the importance of WX to air traffic safety is truly ignorant.

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Original NASA ASRS Text

Title: RPT ALLEGES THE ASOS IS UNSAFE FOR AIR TFC WITHOUT AUGMENTATION AND BACKUP.

Narrative: I AM A WX OBSERVER WHOSE JOB IS TO AUGMENT THE ASOS (AUTOMATED SURFACE OBSERVING SYS) WHENEVER I DEEM NECESSARY. THIS MUST BE DONE NEARLY CONSTANTLY IN ORDER TO ACCURATELY REFLECT CURRENT WX CONDITIONS. IN WRITING THIS, I AM NOT JUST CITING ONE PARTICULAR INCIDENT, BUT RATHER, I AM DESCRIBING MY 2 1/2 YRS EXPERIENCE WITH ASOS AND MY OPINION OF IT. I TRULY FEEL THAT WITHOUT AUGMENTATION AND BACKUP THE ASOS IS UNSAFE FOR AIR TFC. IN MY OPINION, THE SYS WAS DESIGNED TO FAIL. FOR INSTANCE, ITS CEILOMETER ONLY SEES CLOUDS DIRECTLY OVER ITS SENSOR. THIS MEANS ON A DREARY OVCST DAY, IF THERE IS ONE SMALL BREAK IN THE CLOUDS OVER THE SENSOR, IT CALLS THE SKY CLR. FURTHERMORE, THE VISIBILITY SENSORS ARE ALMOST ALWAYS INACCURATE. THEY GENERALLY SHOW THE VISIBILITY TO BE MUCH GREATER THAN IT ACTUALLY IS. BOTH THE CEILING AND VISIBILITY ARE OBVIOUSLY IMPORTANT FACTORS TO THE SAFETY OF AIR TFC. THIS IS ALL NOT EVEN TO MENTION HOW MUCH WX PHENOMENA THE ASOS CAN'T EVEN DETECT: TORNADIC ACTIVITY, TSTMS AND LIGHTNING, HAIL, ICE PELLETS, VIRGA, ETC. ANOTHER PROB WITH ASOS IS ITS CONSTANT NEED OF REPAIR. IT WOULD ACTUALLY BE A RARE EVENT IN WHICH ASOS IS FULLY FUNCTIONAL. FOR EXAMPLE, AT THIS SITE RIGHT NOW THERE ARE 2 ITEMS IN NEED OF SVC, BOTH OF WHICH HAVE BEEN OUT FOR OVER 2 WKS. OUR OFFICE USED TO KEEP A LOG WHERE EVERY TIME AN OBSERVER HAD TO AUGMENT ASOS' RPT OF WX CONDITIONS, WE MADE AN ENTRY. WE NO LONGER KEEP THIS LOG BECAUSE IT IS A PRACTICALLY IMPOSSIBLE AND OVERWHELMING TASK. I DO NOT HAVE TO IMAGINE HOW INACCURATELY ASOS RPTS WX ON ITS OWN, I SEE IT EVERY DAY. ANYONE WHO DOES NOT RECOGNIZE THE IMPORTANCE OF WX TO AIR TFC SAFETY IS TRULY IGNORANT.

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.