Narrative:

We were departing dsv en route to florida via lyh then sav to vnc. We arrived at dsv approximately XA15 and while we prepared the airplane, valley fog was forming. Stars were visible above but horizontal visibility dropped rapidly. Decided to call buf FSS and requested they move back the IFR flight plan departure time because of the fog. They (FSS) had to call roc approach because the plan had been filed with and by duat. This also notified roc of the fog conditions in the dansville valley. We waited for the fog to dissipate. We considered obtaining a void time clearance but the conditions were varying enough that we rejected this because we wanted to select conditions without the pressure of a time constraint. About XB40 the sun rose above the east hills adjoining the airport. When this happened, it caused a clearing and visibility extended beyond the end of runway 32 and the west and northwest hills were clearly visible. We started and took off on runway 32 before XC00. We were able to climb out clear of mist/fog, and clouds and were above everything else by 200-300 ft AGL. Visibility was clear forward and above but there were many areas of ground fog. At this time roc was below minimums and acrs were being directed to holds. The roc controller questioned us quite a bit about our immediate conditions, ie, VFR/IMC and about surrounding areas. I guess I'm a bit paranoid but I know I wouldn't and did not violate the FARS but I suspect the controller may have thought so. We took off in uncontrolled airspace, above the minimums for that airspace.

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Original NASA ASRS Text

Title: SMA PLT TRYING TO DEPART NON TWR ARPT ON IFR CLRNC HAS PROB WITH FOG AND WAITS FOR IT TO DISSIPATE. ON DEP ATC QUESTIONS THE CONDITIONS SINCE A MAJOR ARPT HAS FOG AND IS PLACING ACFT IN HOLDING PATTERNS.

Narrative: WE WERE DEPARTING DSV ENRTE TO FLORIDA VIA LYH THEN SAV TO VNC. WE ARRIVED AT DSV APPROX XA15 AND WHILE WE PREPARED THE AIRPLANE, VALLEY FOG WAS FORMING. STARS WERE VISIBLE ABOVE BUT HORIZ VISIBILITY DROPPED RAPIDLY. DECIDED TO CALL BUF FSS AND REQUESTED THEY MOVE BACK THE IFR FLT PLAN DEP TIME BECAUSE OF THE FOG. THEY (FSS) HAD TO CALL ROC APCH BECAUSE THE PLAN HAD BEEN FILED WITH AND BY DUAT. THIS ALSO NOTIFIED ROC OF THE FOG CONDITIONS IN THE DANSVILLE VALLEY. WE WAITED FOR THE FOG TO DISSIPATE. WE CONSIDERED OBTAINING A VOID TIME CLRNC BUT THE CONDITIONS WERE VARYING ENOUGH THAT WE REJECTED THIS BECAUSE WE WANTED TO SELECT CONDITIONS WITHOUT THE PRESSURE OF A TIME CONSTRAINT. ABOUT XB40 THE SUN ROSE ABOVE THE E HILLS ADJOINING THE ARPT. WHEN THIS HAPPENED, IT CAUSED A CLRING AND VISIBILITY EXTENDED BEYOND THE END OF RWY 32 AND THE W AND NW HILLS WERE CLRLY VISIBLE. WE STARTED AND TOOK OFF ON RWY 32 BEFORE XC00. WE WERE ABLE TO CLB OUT CLR OF MIST/FOG, AND CLOUDS AND WERE ABOVE EVERYTHING ELSE BY 200-300 FT AGL. VISIBILITY WAS CLR FORWARD AND ABOVE BUT THERE WERE MANY AREAS OF GND FOG. AT THIS TIME ROC WAS BELOW MINIMUMS AND ACRS WERE BEING DIRECTED TO HOLDS. THE ROC CTLR QUESTIONED US QUITE A BIT ABOUT OUR IMMEDIATE CONDITIONS, IE, VFR/IMC AND ABOUT SURROUNDING AREAS. I GUESS I'M A BIT PARANOID BUT I KNOW I WOULDN'T AND DID NOT VIOLATE THE FARS BUT I SUSPECT THE CTLR MAY HAVE THOUGHT SO. WE TOOK OFF IN UNCTLED AIRSPACE, ABOVE THE MINIMUMS FOR THAT AIRSPACE.

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.