Narrative:

I started engine after towing and parking agricultural airplane at load ramp. Started engine after hooking up load hose and standing on wing walk. Set throttle for low RPM warm up. Walked back to mix area and proceeded to mix load of propanil for spray on rice after loading it in airplane. Noticed change in sound of engine, like airplane taxiing away. I jumped down and ran to catch airplane just before it stretched to the end of the load hose. Shut off switch and got it stopped. Could have been disastrous.

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Original NASA ASRS Text

Title: SMA PLT STARTED ENGINE, THEN LEFT ACFT TO LOAD AGR SPRAY AND ACFT STARTED TAXI AWAY WITH NO PLT.

Narrative: I STARTED ENG AFTER TOWING AND PARKING AGRICULTURAL AIRPLANE AT LOAD RAMP. STARTED ENG AFTER HOOKING UP LOAD HOSE AND STANDING ON WING WALK. SET THROTTLE FOR LOW RPM WARM UP. WALKED BACK TO MIX AREA AND PROCEEDED TO MIX LOAD OF PROPANIL FOR SPRAY ON RICE AFTER LOADING IT IN AIRPLANE. NOTICED CHANGE IN SOUND OF ENG, LIKE AIRPLANE TAXIING AWAY. I JUMPED DOWN AND RAN TO CATCH AIRPLANE JUST BEFORE IT STRETCHED TO THE END OF THE LOAD HOSE. SHUT OFF SWITCH AND GOT IT STOPPED. COULD HAVE BEEN DISASTROUS.

Data retrieved from NASA's ASRS site as of August 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.