A J-3 CUB PILOT MADE AN OFF-AIRPORT LANDING WHEN HIS ENGINE FAILED BECAUSE OF FUEL STARVATION APPARENTLY CAUSED BY A LEAKING FUEL SAMPLE DRAIN VALVE.

Narrative

I WAS STARTING A DSCNT INTO ZZZ WHEN I EXPERIENCED A ROUGH RUNNING ENG. I REPOSITIONED THE THROTTLE SEVERAL TIMES AND SHORTLY THE ENG QUIT RUNNING COMPLETELY. I PULLED THE STICK BACK; AND PUT THE ACFT INTO THE BEST GLIDE SPD; AND POINTED THE NOSE DIRECTLY AT THE ARPT. MY ALT WAS APPROX 2800 FT. AS I GLIDED TOWARDS THE ARPT I MADE SEVERAL CALLS IN THE BLIND ON THE UNICOM FREQ OF THE RADIO; BUT I DID NOT RECEIVE AN ANSWER. AS I APCHED THE ARPT; I BEGAN TO SET UP FOR A STRAIGHT IN TO RWY 35. AT ABOUT A MI OR LESS; IT WAS APPARENT THAT THE STEEP TERRAIN ON MY APCH TO THE RWY; AND THE VERY BUSY VEHICLE TFC ON THE ONLY STREET BELOW; MADE ME DECIDE TO TURN L AND SEEK AN ALTERNATIVE LNDG SPOT. I LOCATED A WIDE STREET IN THE RESIDENTIAL NEIGHBORHOOD WITH NO CARS OR OVERHEAD LINES ON THE STREETS; AND LINED UP FOR AN OFF ARPT LNDG. I WAS ABLE TO LAND THE ACFT ON THE STREET; AND WAS ROLLING TO A STOP WHEN THE L WING HIT A GROUP OF TRASH CANS AND CAUSED ME TO LOSE CTL. MY L WING CLIPPED A TREE AND I CAME TO AN ABRUPT STOP ON THE SIDEWALK AND PARKING AREA OF THE STREET. AFTER THE REMOVAL AND RETURN TO THE ARPT OF THE ACFT; I NOTED A DISCOLORATION STREAK DOWN THE BELLY OF THE ACFT. IT APPEARS THE LOW POINT DRAIN/FUEL SUMP WAS LEAKING DURING THE FLT. THIS WAS THE CAUSE OF THE ENG FAILURE; A LACK OF FUEL. MY FLT TIME WAS UNDER 2 HRS. I DEPARTED WITH FULL FUEL OR 12 GALS. FUEL BURN IS LESS THAN 5 GPH AND MY FLT PLAN CALLED FOR A 3 GAL RESERVE AT LNDG. AIR CONDITIONS WERE CLR; 50 MI VISIBILITY; WIND CALM; AND A 2 KT TAILWIND. DUE TO THE PRIMITIVE FUEL GAUGE ON THE ACFT IT WOULD BE EXTREMELY DIFFICULT TO DETERMINE THE FUEL TANK WAS EMPTY. THE FUEL GAUGE IS A CORK ON A ROD THAT FLOATS IN THE FUEL TO ESTIMATE THE LEVEL. THIS TYPE OF ACFT IS NORMALLY FLOW BY TIME AND DISTANCE CALCULATIONS FOR ESTIMATING FUEL USE.