Narrative:

On jun/xa/01, I planned and executed a flight plan and flight from rifle, co, to santa rosa, ca. My planned fuel stop was to be tonopah, nv, at my expected 4.5 hour after departure from ril. I expected light headwinds, per the WX briefing I obtained. The plane was a C172 recently out of a 100 hour inspection and I was familiar with the aircraft and had at least 20+ hours initial (I haven't added them). The plane has extended range tanks (54 gals) and we normally plan at 8 gph. This day I planned 8 gph and left myself 2.25 hour reserve fuel. The flight was going fine and I was concentrating on avoiding a 'hot MOA' north and east of tonopah. Before I reached tonopah, the fuel gauges quickly receded to low levels and I switched to one side. At about 50 mi out, that tank ran out. I switched to the second tank. I was already slowed to best cruise, 75 KTS or so. I was descending from 11500 ft from over the mountains and at about 14 mi out of tonopah, my last tank was running dry. I was able to glide for another 4 or 5 mi following a highway beneath me and losing altitude. I landed without any damage whatsoever, no traffic on highway, coasted off the shoulder and got word to arrange fuel from tonopah. We put 10 gals in plane and flew to tonopah to top-off. The rest of the flight went fine. Back to rifle, on jun/xc/01, and discussed this incident with the maintenance supervisor where I rented the plane. I showed him my fuel and time logs and he downed the plane until he could check it out. I later found out the fuel caps or cap may have been leaking and siphoning fuel. Still not determined by the a&P, but I notified him of this, and he stated he already was thinking on that same track. The plane to that point burned well over 11 gph almost 12.

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Original NASA ASRS Text

Title: C172 PLT HAD FORCED LNDG DUE TO FUEL STARVATION CAUSED BY A FUEL LEAK.

Narrative: ON JUN/XA/01, I PLANNED AND EXECUTED A FLT PLAN AND FLT FROM RIFLE, CO, TO SANTA ROSA, CA. MY PLANNED FUEL STOP WAS TO BE TONOPAH, NV, AT MY EXPECTED 4.5 HR AFTER DEP FROM RIL. I EXPECTED LIGHT HEADWINDS, PER THE WX BRIEFING I OBTAINED. THE PLANE WAS A C172 RECENTLY OUT OF A 100 HR INSPECTION AND I WAS FAMILIAR WITH THE ACFT AND HAD AT LEAST 20+ HRS INITIAL (I HAVEN'T ADDED THEM). THE PLANE HAS EXTENDED RANGE TANKS (54 GALS) AND WE NORMALLY PLAN AT 8 GPH. THIS DAY I PLANNED 8 GPH AND LEFT MYSELF 2.25 HR RESERVE FUEL. THE FLT WAS GOING FINE AND I WAS CONCENTRATING ON AVOIDING A 'HOT MOA' N AND E OF TONOPAH. BEFORE I REACHED TONOPAH, THE FUEL GAUGES QUICKLY RECEDED TO LOW LEVELS AND I SWITCHED TO ONE SIDE. AT ABOUT 50 MI OUT, THAT TANK RAN OUT. I SWITCHED TO THE SECOND TANK. I WAS ALREADY SLOWED TO BEST CRUISE, 75 KTS OR SO. I WAS DSNDING FROM 11500 FT FROM OVER THE MOUNTAINS AND AT ABOUT 14 MI OUT OF TONOPAH, MY LAST TANK WAS RUNNING DRY. I WAS ABLE TO GLIDE FOR ANOTHER 4 OR 5 MI FOLLOWING A HWY BENEATH ME AND LOSING ALT. I LANDED WITHOUT ANY DAMAGE WHATSOEVER, NO TFC ON HWY, COASTED OFF THE SHOULDER AND GOT WORD TO ARRANGE FUEL FROM TONOPAH. WE PUT 10 GALS IN PLANE AND FLEW TO TONOPAH TO TOP-OFF. THE REST OF THE FLT WENT FINE. BACK TO RIFLE, ON JUN/XC/01, AND DISCUSSED THIS INCIDENT WITH THE MAINT SUPVR WHERE I RENTED THE PLANE. I SHOWED HIM MY FUEL AND TIME LOGS AND HE DOWNED THE PLANE UNTIL HE COULD CHK IT OUT. I LATER FOUND OUT THE FUEL CAPS OR CAP MAY HAVE BEEN LEAKING AND SIPHONING FUEL. STILL NOT DETERMINED BY THE A&P, BUT I NOTIFIED HIM OF THIS, AND HE STATED HE ALREADY WAS THINKING ON THAT SAME TRACK. THE PLANE TO THAT POINT BURNED WELL OVER 11 GPH ALMOST 12.

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.