Narrative:

On may/sun/92, at approximately XA50 hours, I was giving dual instruction in a world war 2 aircraft. The student performed his preflight, and upon completion, entered the front cockpit to adjust his seat, seatbelts, etc. I then performed my preflight and found the aircraft to be ready for flight. I proceeded to secure the baggage compartment door located on the left side of the fuselage and to get our headsets on; at this time, I noticed a fuel truck had parked in front of our aircraft. I told the driver that we did not need fuel and he proceeded to drive away. Unknown to me and my student, he had removed or loosened the right side and left side fuel caps, and did not replace or retighten them we completed securing ourselves in the cockpit, and taxied for takeoff. After about 40 mi of flight, I noticed white smoke on the right side of the aircraft. Upon closer observation, I found this to be a fire. I surmised that the venting evaporating fuel mixture was ignited by the exhaust which exits on the right side of the fuselage adjacent to the fuel filler. I immediately notified the student in the front cockpit, and took over the flight controls. I put the aircraft in a dive which put out the fire. The student was then instructed to get the ATIS and a landing clearance at our home airport. I surveyed the aircraft for damage but could find none other than 2 missing fuel caps. I had full control usage at this time and proceeded to make a straight-in landing on the duty runway. Upon landing, I received permission to turn off and park on the grass. I requested a tow vehicle and secured the engine. The right side of the wing and empennage were black with soot, but appeared to be in good condition. About an hour later, both fuel caps were found on the ramp vicinity of where the aircraft was parked. This matter was reported to the NTSB jun/mon/92.

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Original NASA ASRS Text

Title: 2 HIGH TIME PLTS HAD A FIRE IN FLT FROM GASOLINE SYPHONING FROM 1 OF THE WING FUEL TANKS OF A WORLD WAR 2 TRAINER.

Narrative: ON MAY/SUN/92, AT APPROX XA50 HRS, I WAS GIVING DUAL INSTRUCTION IN A WORLD WAR 2 ACFT. THE STUDENT PERFORMED HIS PREFLT, AND UPON COMPLETION, ENTERED THE FRONT COCKPIT TO ADJUST HIS SEAT, SEATBELTS, ETC. I THEN PERFORMED MY PREFLT AND FOUND THE ACFT TO BE READY FOR FLT. I PROCEEDED TO SECURE THE BAGGAGE COMPARTMENT DOOR LOCATED ON THE L SIDE OF THE FUSELAGE AND TO GET OUR HEADSETS ON; AT THIS TIME, I NOTICED A FUEL TRUCK HAD PARKED IN FRONT OF OUR ACFT. I TOLD THE DRIVER THAT WE DID NOT NEED FUEL AND HE PROCEEDED TO DRIVE AWAY. UNKNOWN TO ME AND MY STUDENT, HE HAD REMOVED OR LOOSENED THE R SIDE AND L SIDE FUEL CAPS, AND DID NOT REPLACE OR RETIGHTEN THEM WE COMPLETED SECURING OURSELVES IN THE COCKPIT, AND TAXIED FOR TKOF. AFTER ABOUT 40 MI OF FLT, I NOTICED WHITE SMOKE ON THE R SIDE OF THE ACFT. UPON CLOSER OBSERVATION, I FOUND THIS TO BE A FIRE. I SURMISED THAT THE VENTING EVAPORATING FUEL MIXTURE WAS IGNITED BY THE EXHAUST WHICH EXITS ON THE R SIDE OF THE FUSELAGE ADJACENT TO THE FUEL FILLER. I IMMEDIATELY NOTIFIED THE STUDENT IN THE FRONT COCKPIT, AND TOOK OVER THE FLT CTLS. I PUT THE ACFT IN A DIVE WHICH PUT OUT THE FIRE. THE STUDENT WAS THEN INSTRUCTED TO GET THE ATIS AND A LNDG CLRNC AT OUR HOME ARPT. I SURVEYED THE ACFT FOR DAMAGE BUT COULD FIND NONE OTHER THAN 2 MISSING FUEL CAPS. I HAD FULL CTL USAGE AT THIS TIME AND PROCEEDED TO MAKE A STRAIGHT-IN LNDG ON THE DUTY RWY. UPON LNDG, I RECEIVED PERMISSION TO TURN OFF AND PARK ON THE GRASS. I REQUESTED A TOW VEHICLE AND SECURED THE ENG. THE R SIDE OF THE WING AND EMPENNAGE WERE BLACK WITH SOOT, BUT APPEARED TO BE IN GOOD CONDITION. ABOUT AN HR LATER, BOTH FUEL CAPS WERE FOUND ON THE RAMP VICINITY OF WHERE THE ACFT WAS PARKED. THIS MATTER WAS RPTED TO THE NTSB JUN/MON/92.

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.