Narrative:

The following narrative describes my balloon flight on the morning of aug/sat/01 in some detail. The flight was delightful, a complete success and its safe outcome was never in doubt, but I learned a lesson that may be worth sharing. Surface winds were from the northeast, with perhaps a slight turn to the right as we rose. But above 1000 ft AGL, the winds were completely calm. I had hoped to be able to box back to the east and land on the airport again to swap passenger, but I found no cooperative winds at the altitudes I explored. About 10 mins into the flight, I noticed a change in the sound of the burner, and discovered that I was down to about 15% fuel in my first tank. Normally, each of my tanks would last longer than that, but I had made a slight change in my procedures that morning that I thought might account for the discrepancy. My 4 tanks share a common fuel manifold (hose) running to the burner, and it's my habit to run each tank down to 20%, then switch to the next tank in a predetermined order: blue, green, yellow, then red. At the upstream end of the manifold is a quick-release joint to which I attach another hose when refueling. This quick-release valve closes automatically when unattached, but it is also protected by another valve just downstream, which adds another level of protection against leaks. Without the 5TH tank, I had to inflate off my blue tank, which I reckoned might have caused the abnormal fuel consumption. At any rate, I switched to the green tank and noted that it was not yet registering -- the gauges on my tanks only register when the tanks are less than 35% full. The flight continued as normal. A few mins later, I noticed that the green tank was now registering, and in fact it seemed to me that the fuel gauge was moving lower at a visible rate. Now I was worried. Since both tanks had seemed full on the ground, I checked the line pressure from each tank as I do my burner check. I could only assume that I had a leak in my fuel system somewhere. I theorized that the valve controled by the missing knob was actually in the 'open' position, had been for some time, and that the fuel pressure had loosened the quick-release valve. My passenger and I sniffed around for a fuel leak, but didn't smell anything. At this point I decided to look for the most expeditious landing opportunity. I dropped down to 100 ft or so and began looking ahead for landing spots. Unfortunately, we were in very light winds and over a densely settled area. As we flew by our crew, the wind shifted slightly to our left and lined us up right down a parking lot itself. It's actually a fine landing spot on a calm day: 76 X 113 paces (bigger than a football field). I made a near perfect approach and landing, easy in such light wind. We stopped after about 10 ft of skid, with the balloon standing up, in the northwest quadrant of the parking lot. To return to the interesting issue of fuel management, after packing up I called my former instructor, who had just flown in to a nearby town. I explained my fuel leak theory and then headed down to the near by town to meet him. If I had a fuel leak, I wasn't going to refuel before bringing the balloon in to the repair station. My former instructor's theory, which I believe, is that I had simply forgotten to refuel after my last flight. I had recently flown in las vegas (my balloon stayed down south after an event last yr, since we can't fly here until summer anyway). After that flight, I hadn't refueled since I knew I would be headed back north and reckoned I'd be safer and faster on the road with empty tanks in the trailer. The balloon has been back in washington since april, and I'd been out already 3 times this season, but not in my own balloon. I guess the time lapse and intermediate activities had conspired to help me forget that I hadn't refueled after flying like I normally do. Although I won't likely make this particular mistake again, it bothers me that I didn't have a probe in place beforehand to detect this kind of error. I've asked around what the best way is to check fuel quantity before a flight,and heard the following suggestions: first, make sure you check the gauge -- I will from now on. Second, open the split valve on each tank. I've tried this a few times since but don't love it, mainly because it spreads the smell of fuel all around the basket, which prevents me from sniffing for fuel leaks (a great danger). It's also hard to distinguish splitting vapor from splitting liquid under those circumstances. I'm not sure refueled tank would split after settling or a drop in temperature. I'm told we can shake them to make them split, but if that works at any fuel level, it defeats the purpose of the test. I'll keep experimenting with it, though. We can focus not on checking fuel during preflight but instead on making sure we've refueled before flying, on the generally valid assumption that any fuel you've put in is still there. My first idea was to mark the tanks with an empty flag if I don't refuel after flying, but a few days later the propane supply tank was empty when I went to refuel, and out of laziness I didn't reopen the trailer to mark the tanks. Now I think I should mark them empty as I switch tanks in-flight. Any better ideas?

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Original NASA ASRS Text

Title: A LOW TIME BALLOONIST IN A GALAXY 7 FINDS NEW WAYS TO CUT SHORT A PLEASURE FLT.

Narrative: THE FOLLOWING NARRATIVE DESCRIBES MY BALLOON FLT ON THE MORNING OF AUG/SAT/01 IN SOME DETAIL. THE FLT WAS DELIGHTFUL, A COMPLETE SUCCESS AND ITS SAFE OUTCOME WAS NEVER IN DOUBT, BUT I LEARNED A LESSON THAT MAY BE WORTH SHARING. SURFACE WINDS WERE FROM THE NE, WITH PERHAPS A SLIGHT TURN TO THE R AS WE ROSE. BUT ABOVE 1000 FT AGL, THE WINDS WERE COMPLETELY CALM. I HAD HOPED TO BE ABLE TO BOX BACK TO THE E AND LAND ON THE ARPT AGAIN TO SWAP PAX, BUT I FOUND NO COOPERATIVE WINDS AT THE ALTS I EXPLORED. ABOUT 10 MINS INTO THE FLT, I NOTICED A CHANGE IN THE SOUND OF THE BURNER, AND DISCOVERED THAT I WAS DOWN TO ABOUT 15% FUEL IN MY FIRST TANK. NORMALLY, EACH OF MY TANKS WOULD LAST LONGER THAN THAT, BUT I HAD MADE A SLIGHT CHANGE IN MY PROCS THAT MORNING THAT I THOUGHT MIGHT ACCOUNT FOR THE DISCREPANCY. MY 4 TANKS SHARE A COMMON FUEL MANIFOLD (HOSE) RUNNING TO THE BURNER, AND IT'S MY HABIT TO RUN EACH TANK DOWN TO 20%, THEN SWITCH TO THE NEXT TANK IN A PREDETERMINED ORDER: BLUE, GREEN, YELLOW, THEN RED. AT THE UPSTREAM END OF THE MANIFOLD IS A QUICK-RELEASE JOINT TO WHICH I ATTACH ANOTHER HOSE WHEN REFUELING. THIS QUICK-RELEASE VALVE CLOSES AUTOMATICALLY WHEN UNATTACHED, BUT IT IS ALSO PROTECTED BY ANOTHER VALVE JUST DOWNSTREAM, WHICH ADDS ANOTHER LEVEL OF PROTECTION AGAINST LEAKS. WITHOUT THE 5TH TANK, I HAD TO INFLATE OFF MY BLUE TANK, WHICH I RECKONED MIGHT HAVE CAUSED THE ABNORMAL FUEL CONSUMPTION. AT ANY RATE, I SWITCHED TO THE GREEN TANK AND NOTED THAT IT WAS NOT YET REGISTERING -- THE GAUGES ON MY TANKS ONLY REGISTER WHEN THE TANKS ARE LESS THAN 35% FULL. THE FLT CONTINUED AS NORMAL. A FEW MINS LATER, I NOTICED THAT THE GREEN TANK WAS NOW REGISTERING, AND IN FACT IT SEEMED TO ME THAT THE FUEL GAUGE WAS MOVING LOWER AT A VISIBLE RATE. NOW I WAS WORRIED. SINCE BOTH TANKS HAD SEEMED FULL ON THE GND, I CHKED THE LINE PRESSURE FROM EACH TANK AS I DO MY BURNER CHK. I COULD ONLY ASSUME THAT I HAD A LEAK IN MY FUEL SYS SOMEWHERE. I THEORIZED THAT THE VALVE CTLED BY THE MISSING KNOB WAS ACTUALLY IN THE 'OPEN' POS, HAD BEEN FOR SOME TIME, AND THAT THE FUEL PRESSURE HAD LOOSENED THE QUICK-RELEASE VALVE. MY PAX AND I SNIFFED AROUND FOR A FUEL LEAK, BUT DIDN'T SMELL ANYTHING. AT THIS POINT I DECIDED TO LOOK FOR THE MOST EXPEDITIOUS LNDG OPPORTUNITY. I DROPPED DOWN TO 100 FT OR SO AND BEGAN LOOKING AHEAD FOR LNDG SPOTS. UNFORTUNATELY, WE WERE IN VERY LIGHT WINDS AND OVER A DENSELY SETTLED AREA. AS WE FLEW BY OUR CREW, THE WIND SHIFTED SLIGHTLY TO OUR L AND LINED US UP RIGHT DOWN A PARKING LOT ITSELF. IT'S ACTUALLY A FINE LNDG SPOT ON A CALM DAY: 76 X 113 PACES (BIGGER THAN A FOOTBALL FIELD). I MADE A NEAR PERFECT APCH AND LNDG, EASY IN SUCH LIGHT WIND. WE STOPPED AFTER ABOUT 10 FT OF SKID, WITH THE BALLOON STANDING UP, IN THE NW QUADRANT OF THE PARKING LOT. TO RETURN TO THE INTERESTING ISSUE OF FUEL MGMNT, AFTER PACKING UP I CALLED MY FORMER INSTRUCTOR, WHO HAD JUST FLOWN IN TO A NEARBY TOWN. I EXPLAINED MY FUEL LEAK THEORY AND THEN HEADED DOWN TO THE NEAR BY TOWN TO MEET HIM. IF I HAD A FUEL LEAK, I WASN'T GOING TO REFUEL BEFORE BRINGING THE BALLOON IN TO THE REPAIR STATION. MY FORMER INSTRUCTOR'S THEORY, WHICH I BELIEVE, IS THAT I HAD SIMPLY FORGOTTEN TO REFUEL AFTER MY LAST FLT. I HAD RECENTLY FLOWN IN LAS VEGAS (MY BALLOON STAYED DOWN S AFTER AN EVENT LAST YR, SINCE WE CAN'T FLY HERE UNTIL SUMMER ANYWAY). AFTER THAT FLT, I HADN'T REFUELED SINCE I KNEW I WOULD BE HEADED BACK N AND RECKONED I'D BE SAFER AND FASTER ON THE ROAD WITH EMPTY TANKS IN THE TRAILER. THE BALLOON HAS BEEN BACK IN WASHINGTON SINCE APRIL, AND I'D BEEN OUT ALREADY 3 TIMES THIS SEASON, BUT NOT IN MY OWN BALLOON. I GUESS THE TIME LAPSE AND INTERMEDIATE ACTIVITIES HAD CONSPIRED TO HELP ME FORGET THAT I HADN'T REFUELED AFTER FLYING LIKE I NORMALLY DO. ALTHOUGH I WON'T LIKELY MAKE THIS PARTICULAR MISTAKE AGAIN, IT BOTHERS ME THAT I DIDN'T HAVE A PROBE IN PLACE BEFOREHAND TO DETECT THIS KIND OF ERROR. I'VE ASKED AROUND WHAT THE BEST WAY IS TO CHK FUEL QUANTITY BEFORE A FLT,AND HEARD THE FOLLOWING SUGGESTIONS: FIRST, MAKE SURE YOU CHK THE GAUGE -- I WILL FROM NOW ON. SECOND, OPEN THE SPLIT VALVE ON EACH TANK. I'VE TRIED THIS A FEW TIMES SINCE BUT DON'T LOVE IT, MAINLY BECAUSE IT SPREADS THE SMELL OF FUEL ALL AROUND THE BASKET, WHICH PREVENTS ME FROM SNIFFING FOR FUEL LEAKS (A GREAT DANGER). IT'S ALSO HARD TO DISTINGUISH SPLITTING VAPOR FROM SPLITTING LIQUID UNDER THOSE CIRCUMSTANCES. I'M NOT SURE REFUELED TANK WOULD SPLIT AFTER SETTLING OR A DROP IN TEMP. I'M TOLD WE CAN SHAKE THEM TO MAKE THEM SPLIT, BUT IF THAT WORKS AT ANY FUEL LEVEL, IT DEFEATS THE PURPOSE OF THE TEST. I'LL KEEP EXPERIMENTING WITH IT, THOUGH. WE CAN FOCUS NOT ON CHKING FUEL DURING PREFLT BUT INSTEAD ON MAKING SURE WE'VE REFUELED BEFORE FLYING, ON THE GENERALLY VALID ASSUMPTION THAT ANY FUEL YOU'VE PUT IN IS STILL THERE. MY FIRST IDEA WAS TO MARK THE TANKS WITH AN EMPTY FLAG IF I DON'T REFUEL AFTER FLYING, BUT A FEW DAYS LATER THE PROPANE SUPPLY TANK WAS EMPTY WHEN I WENT TO REFUEL, AND OUT OF LAZINESS I DIDN'T REOPEN THE TRAILER TO MARK THE TANKS. NOW I THINK I SHOULD MARK THEM EMPTY AS I SWITCH TANKS INFLT. ANY BETTER IDEAS?

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.