Narrative:

During engine startup, engine failed to start after numerous attempts. I allowed engine to situation for approximately 2 min, then applied 2 shots of primer, and opened the throttle. I then exited the aircraft to pull the propeller through several blades to prime the engine. On the second slow pull, the engine fired. I ran to the door, attempted to restrain the aircraft and open the now closed door to stop the engine. The aircraft did 2 complete ground loops in an open area before the left main gear collapsed and the propeller struck, stopping the engine. Upon inspection of the cockpit, I found that while I had switched off the master, I had neglected to switch off the magnetos. Problem across -- failure of engine start and failure of pilot to switch off magnetos while manually priming engine. Contributing factors -- distrs involved in exiting cockpit to prime engine. Doing something out of your normal routine/procedures. How it was discovered -- engine started. Corrective action -- always treat an engine as 'hot' when turning the propeller. Tie tail and remove key. Double check that magnetos are off. Even though you are not attempting to start an engine, assume that it will start.

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Original NASA ASRS Text

Title: PA22 PLT HAND PROPPED ENG WITHOUT TURNING THE MAGNETO SWITCH OFF. THE ENG STARTED WITH NO PLT ABOARD AND WAS DAMAGED.

Narrative: DURING ENG STARTUP, ENG FAILED TO START AFTER NUMEROUS ATTEMPTS. I ALLOWED ENG TO SIT FOR APPROX 2 MIN, THEN APPLIED 2 SHOTS OF PRIMER, AND OPENED THE THROTTLE. I THEN EXITED THE ACFT TO PULL THE PROP THROUGH SEVERAL BLADES TO PRIME THE ENG. ON THE SECOND SLOW PULL, THE ENG FIRED. I RAN TO THE DOOR, ATTEMPTED TO RESTRAIN THE ACFT AND OPEN THE NOW CLOSED DOOR TO STOP THE ENG. THE ACFT DID 2 COMPLETE GND LOOPS IN AN OPEN AREA BEFORE THE L MAIN GEAR COLLAPSED AND THE PROP STRUCK, STOPPING THE ENG. UPON INSPECTION OF THE COCKPIT, I FOUND THAT WHILE I HAD SWITCHED OFF THE MASTER, I HAD NEGLECTED TO SWITCH OFF THE MAGNETOS. PROB ACROSS -- FAILURE OF ENG START AND FAILURE OF PLT TO SWITCH OFF MAGNETOS WHILE MANUALLY PRIMING ENG. CONTRIBUTING FACTORS -- DISTRS INVOLVED IN EXITING COCKPIT TO PRIME ENG. DOING SOMETHING OUT OF YOUR NORMAL ROUTINE/PROCS. HOW IT WAS DISCOVERED -- ENG STARTED. CORRECTIVE ACTION -- ALWAYS TREAT AN ENG AS 'HOT' WHEN TURNING THE PROP. TIE TAIL AND REMOVE KEY. DOUBLE CHK THAT MAGNETOS ARE OFF. EVEN THOUGH YOU ARE NOT ATTEMPTING TO START AN ENG, ASSUME THAT IT WILL START.

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.