Narrative:

The student and I conducted a complete pre flight of the aircraft and all procedures appeared normal. However; upon sumping the engine sump for fuel; the butterfly clip may have gotten stuck on the cowling. However this was easily overlooked as no more fuel was spilling from the sump. Normal startup; taxi and runup procedures were performed and no abnormalities occurred. Upon takeoff total power loss was encountered at about 50 ft AGL. I; the instructor; immediately took over and safely landed the aircraft on grass inside airport property. No damage was inflicted on the aircraft; airport property; or beings during the event. The cause of the power loss is still unknown; however I can say I learned a valuable lesson. A thorough preflight is key to a safe flight. Checking all engine components is required and cannot be overlooked.

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Original NASA ASRS Text

Title: PA28 Instructor Pilot experiences a power failure at 50 FT AGL with the student at the controls. The Instructor takes control and successfully lands on airport property with no damage to airport or aircraft. Fuel starvation is suspected.

Narrative: The student and I conducted a complete pre flight of the aircraft and all procedures appeared normal. However; upon sumping the engine sump for fuel; the butterfly clip may have gotten stuck on the cowling. However this was easily overlooked as no more fuel was spilling from the sump. Normal startup; taxi and runup procedures were performed and no abnormalities occurred. Upon takeoff total power loss was encountered at about 50 FT AGL. I; the Instructor; immediately took over and safely landed the aircraft on grass inside airport property. No damage was inflicted on the aircraft; airport property; or beings during the event. The cause of the power loss is still unknown; however I can say I learned a valuable lesson. A thorough preflight is key to a safe flight. Checking ALL engine components is required and cannot be overlooked.

Data retrieved from NASA's ASRS site as of July 2013 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.