Narrative:

We were departing an uncontrolled airport that has a WX reporting service on the field. The WX observer gives his reports to unicom to be passed onto aircraft. We left the gate at XX45 and taxied for departure. While taxiing out we made 2 attempts to contact unicom but got no answer. Fog was thickening and we wanted to get the latest reported WX before departing. The most recent reported WX was above our takeoff minimums. Since we couldn't get a response from unicom, we asked ZMP for their latest WX at our airport when we called them for departure clearance. The most current WX that center had showed the visibility to be 1/4 mi. I stated that our takeoff minimums were 1/4 mi, and ZMP gave us our clearance. We could easily see beyond 1/4 mi down the runway. Since we had no reason to believe that the WX was below our minimums, we took off at XX55. Later in the day an FAA inspector met us at our plane to ask us about the eau claire departure. Apparently the WX observer put out a record special report at XX50 showing the visibility to be 1/8 mi. When the WX observer saw us depart at XX55 he felt that we intentionally took off below our minimums. He called the FAA. There is a frequency for green bay flight service on the ground at eau claire. We didn't call them because we assumed that ZMP would have access to the same WX reports as flight service. If the special report came out at XX50 then we were already talking to center and preparing for takeoff. I don't know how we could have gotten a more current WX report.

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Original NASA ASRS Text

Title: FLT CREW OF LTT ACR ALLEGEDLY TOOK OFF IN FOG WITH SPECIAL REPORT BELOW MINIMUMS.

Narrative: WE WERE DEPARTING AN UNCONTROLLED ARPT THAT HAS A WX REPORTING SERVICE ON THE FIELD. THE WX OBSERVER GIVES HIS REPORTS TO UNICOM TO BE PASSED ONTO ACFT. WE LEFT THE GATE AT XX45 AND TAXIED FOR DEP. WHILE TAXIING OUT WE MADE 2 ATTEMPTS TO CONTACT UNICOM BUT GOT NO ANSWER. FOG WAS THICKENING AND WE WANTED TO GET THE LATEST REPORTED WX BEFORE DEPARTING. THE MOST RECENT REPORTED WX WAS ABOVE OUR TKOF MINIMUMS. SINCE WE COULDN'T GET A RESPONSE FROM UNICOM, WE ASKED ZMP FOR THEIR LATEST WX AT OUR ARPT WHEN WE CALLED THEM FOR DEP CLRNC. THE MOST CURRENT WX THAT CENTER HAD SHOWED THE VISIBILITY TO BE 1/4 MI. I STATED THAT OUR TKOF MINIMUMS WERE 1/4 MI, AND ZMP GAVE US OUR CLRNC. WE COULD EASILY SEE BEYOND 1/4 MI DOWN THE RWY. SINCE WE HAD NO REASON TO BELIEVE THAT THE WX WAS BELOW OUR MINIMUMS, WE TOOK OFF AT XX55. LATER IN THE DAY AN FAA INSPECTOR MET US AT OUR PLANE TO ASK US ABOUT THE EAU CLAIRE DEP. APPARENTLY THE WX OBSERVER PUT OUT A RECORD SPECIAL REPORT AT XX50 SHOWING THE VISIBILITY TO BE 1/8 MI. WHEN THE WX OBSERVER SAW US DEPART AT XX55 HE FELT THAT WE INTENTIONALLY TOOK OFF BELOW OUR MINIMUMS. HE CALLED THE FAA. THERE IS A FREQ FOR GREEN BAY FLT SERVICE ON THE GND AT EAU CLAIRE. WE DIDN'T CALL THEM BECAUSE WE ASSUMED THAT ZMP WOULD HAVE ACCESS TO THE SAME WX REPORTS AS FLT SERVICE. IF THE SPECIAL REPORT CAME OUT AT XX50 THEN WE WERE ALREADY TALKING TO CENTER AND PREPARING FOR TKOF. I DON'T KNOW HOW WE COULD HAVE GOTTEN A MORE CURRENT WX REPORT.

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.