Narrative:

On the morning of oct/sun/03, at XA00 CDT a group of 4 balloons met at approximately 5 mi east of mulvane, ks, for a group flight. The forecast for the morning was as follows: 'FM 1000, visibility 3M, P5SM, br SC12, temperature 1014 2SM br, FM 1400 18007 P6SM SC250.' preparation for the flight included launching a pilot balloon to check the direction and speed of the winds aloft. The direction that the pilot balloon took was slowly towards the northeast while close to the ground and gradually turned to the east as it rose above approximately 200 ft. The entire time that we were watching the pilot balloon there was never a question as to whether or not I was going to fly. There was some very low lying ground fog and some that was higher up a few mi to the east, but it was not deemed an impediment to the flight. I launched at approximately XA40 and was following another balloon in the flight of 4. At no time during the climb out was there any visibility problem, at approximately 750 ft AGL and 5 mins into flight the sky was perfectly clear and you could see derby and mulvane, ks, in the distance, 7-10 mi away. However, directly below it was getting very foggy as the fog had lifted and the temperature/dew point had merged, the winds were also no more than 3 mph during the entire time aloft, as measured by the onboard GPS system. For the next few mins the fog got worse and the holes in it where the ground was visible were getting smaller. The other 2 balloons that launched after I did were still up about a mi behind me and were encountering the same conditions and the one that launched before me was about 1/4 mi ahead and to the north of me. I felt that I had no choice other than to continue to fly on and hope to find a big enough area to get down through. I had 2.5 hours of fuel available, so I knew that wasn't a concern for awhile. After about 55 mins the ground fog thinned out, so that only the low lying areas still were covered. I made my first landing in a pasture that was about 3/4 of a mi from any access. I waited there for about 20 mins while the fog continued to dissipate.

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Original NASA ASRS Text

Title: A GROUP OF 4 BALLOONISTS TOOK OFF IN MARGINAL WX, OVERFLYING SOLID GND FOG CONDITIONS 20 MI SE OF ICT, KS.

Narrative: ON THE MORNING OF OCT/SUN/03, AT XA00 CDT A GROUP OF 4 BALLOONS MET AT APPROX 5 MI E OF MULVANE, KS, FOR A GROUP FLT. THE FORECAST FOR THE MORNING WAS AS FOLLOWS: 'FM 1000, VIS 3M, P5SM, BR SC12, TEMP 1014 2SM BR, FM 1400 18007 P6SM SC250.' PREPARATION FOR THE FLT INCLUDED LAUNCHING A PLT BALLOON TO CHK THE DIRECTION AND SPD OF THE WINDS ALOFT. THE DIRECTION THAT THE PLT BALLOON TOOK WAS SLOWLY TOWARDS THE NE WHILE CLOSE TO THE GND AND GRADUALLY TURNED TO THE E AS IT ROSE ABOVE APPROX 200 FT. THE ENTIRE TIME THAT WE WERE WATCHING THE PLT BALLOON THERE WAS NEVER A QUESTION AS TO WHETHER OR NOT I WAS GOING TO FLY. THERE WAS SOME VERY LOW LYING GND FOG AND SOME THAT WAS HIGHER UP A FEW MI TO THE E, BUT IT WAS NOT DEEMED AN IMPEDIMENT TO THE FLT. I LAUNCHED AT APPROX XA40 AND WAS FOLLOWING ANOTHER BALLOON IN THE FLT OF 4. AT NO TIME DURING THE CLBOUT WAS THERE ANY VISIBILITY PROB, AT APPROX 750 FT AGL AND 5 MINS INTO FLT THE SKY WAS PERFECTLY CLR AND YOU COULD SEE DERBY AND MULVANE, KS, IN THE DISTANCE, 7-10 MI AWAY. HOWEVER, DIRECTLY BELOW IT WAS GETTING VERY FOGGY AS THE FOG HAD LIFTED AND THE TEMP/DEW POINT HAD MERGED, THE WINDS WERE ALSO NO MORE THAN 3 MPH DURING THE ENTIRE TIME ALOFT, AS MEASURED BY THE ONBOARD GPS SYS. FOR THE NEXT FEW MINS THE FOG GOT WORSE AND THE HOLES IN IT WHERE THE GND WAS VISIBLE WERE GETTING SMALLER. THE OTHER 2 BALLOONS THAT LAUNCHED AFTER I DID WERE STILL UP ABOUT A MI BEHIND ME AND WERE ENCOUNTERING THE SAME CONDITIONS AND THE ONE THAT LAUNCHED BEFORE ME WAS ABOUT 1/4 MI AHEAD AND TO THE N OF ME. I FELT THAT I HAD NO CHOICE OTHER THAN TO CONTINUE TO FLY ON AND HOPE TO FIND A BIG ENOUGH AREA TO GET DOWN THROUGH. I HAD 2.5 HRS OF FUEL AVAILABLE, SO I KNEW THAT WASN'T A CONCERN FOR AWHILE. AFTER ABOUT 55 MINS THE GND FOG THINNED OUT, SO THAT ONLY THE LOW LYING AREAS STILL WERE COVERED. I MADE MY FIRST LNDG IN A PASTURE THAT WAS ABOUT 3/4 OF A MI FROM ANY ACCESS. I WAITED THERE FOR ABOUT 20 MINS WHILE THE FOG CONTINUED TO DISSIPATE.

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.