Narrative:

After cruising for 42 mins at 6500 ft MSL, I changed tanks from left to right. I turned on the master fuel pump. The engine seemed vapor locked, starved of fuel. I tried pumping the primer and shutting the master on and off. I could not get fuel to the engine. By this time, I glided to 4000 ft, at which point I declared an emergency and looked for a field in order to land. I landed in a corn field. When I checked the tanks on the ground, I found the right tank full.

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Original NASA ASRS Text

Title: A LOW TIME PIPER PLT EXPERIENCED VAPOR LOCK WHILE CHANGING FUEL TANKS, CAUSING THE ENG TO STOP. A FORCED LNDG WAS MADE IN A CORN FIELD.

Narrative: AFTER CRUISING FOR 42 MINS AT 6500 FT MSL, I CHANGED TANKS FROM L TO R. I TURNED ON THE MASTER FUEL PUMP. THE ENG SEEMED VAPOR LOCKED, STARVED OF FUEL. I TRIED PUMPING THE PRIMER AND SHUTTING THE MASTER ON AND OFF. I COULD NOT GET FUEL TO THE ENG. BY THIS TIME, I GLIDED TO 4000 FT, AT WHICH POINT I DECLARED AN EMER AND LOOKED FOR A FIELD IN ORDER TO LAND. I LANDED IN A CORN FIELD. WHEN I CHKED THE TANKS ON THE GND, I FOUND THE R TANK FULL.

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.