Narrative:

I, along with several other pilots, contacted flight service prior to the flight and determined that it was safe to fly. I gave passenger a safety briefing and proceeded with a visual inspection of the balloon. Did not notice any problems with the balloon or its equipment. I proceeded with the inflation and loaded the passenger into the basket. I then took off to 1800 ft AGL. About 10 mins into the flight, I noticed a strong smell of propane. I proceeded to find the source of the smell and noticed icing on the #2 valve of one of the tanks. I immediately isolated the fuel by shutting off the valve and proceeded to find a safe place to land as soon as practical. I touched down on an empty dirt lot away from any homes or buildings. I escorted my passenger out of the basket and proceeded to find the source of the fuel leak. I later determined that the air relief valve on the tank was open, slightly causing the icing of the tank valve, and that there was nothing else wrong. After examining the situation, I believe that I probably could have checked the bleeder valves on the tanks a little better before taking off.

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Original NASA ASRS Text

Title: AN AX10 BALLOON SINGLE PLT MADE AN INADEQUATE PREFLT AND MISSED A CRITICAL ITEM ON HIS FUEL SYS WHICH CAUSED HIM TO MAKE A PRECAUTIONARY LNDG.

Narrative: I, ALONG WITH SEVERAL OTHER PLTS, CONTACTED FLT SVC PRIOR TO THE FLT AND DETERMINED THAT IT WAS SAFE TO FLY. I GAVE PAX A SAFETY BRIEFING AND PROCEEDED WITH A VISUAL INSPECTION OF THE BALLOON. DID NOT NOTICE ANY PROBS WITH THE BALLOON OR ITS EQUIP. I PROCEEDED WITH THE INFLATION AND LOADED THE PAX INTO THE BASKET. I THEN TOOK OFF TO 1800 FT AGL. ABOUT 10 MINS INTO THE FLT, I NOTICED A STRONG SMELL OF PROPANE. I PROCEEDED TO FIND THE SOURCE OF THE SMELL AND NOTICED ICING ON THE #2 VALVE OF ONE OF THE TANKS. I IMMEDIATELY ISOLATED THE FUEL BY SHUTTING OFF THE VALVE AND PROCEEDED TO FIND A SAFE PLACE TO LAND AS SOON AS PRACTICAL. I TOUCHED DOWN ON AN EMPTY DIRT LOT AWAY FROM ANY HOMES OR BUILDINGS. I ESCORTED MY PAX OUT OF THE BASKET AND PROCEEDED TO FIND THE SOURCE OF THE FUEL LEAK. I LATER DETERMINED THAT THE AIR RELIEF VALVE ON THE TANK WAS OPEN, SLIGHTLY CAUSING THE ICING OF THE TANK VALVE, AND THAT THERE WAS NOTHING ELSE WRONG. AFTER EXAMINING THE SIT, I BELIEVE THAT I PROBABLY COULD HAVE CHKED THE BLEEDER VALVES ON THE TANKS A LITTLE BETTER BEFORE TAKING OFF.

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.