Narrative:

Following a normal preflight inspection; taxi; and run-up; I was cleared for takeoff. The takeoff roll was normal. At or slightly after rotation; the engine momentarily hesitated; then resumed normal function. At approximately 100 ft; the engine began running very roughly and producing about 15 percent of the expected power. Further climb was impossible. I declared an emergency and announced my intention to land; landing was uneventful. Time from declaring an emergency to landing was approximately 30 seconds. Post-flight inspection revealed a large (approximately 8 feet long) fuel stain on the left side of the aircraft; on both the left wing and fuselage. Fuel was dripping from the gascolator fuel sump petcock. I suspect that the fuel line near the drain; or the drain itself; suffered a failure. As airspeed increased; the bernoulli effect overcame the engine fuel pump's ability; and caused loss of power through fuel starvation. I routinely brief for engine failure in takeoff. At this airport; my procedure is to land on the remaining runway if possible; otherwise the other runway; otherwise generally ahead. I firmly believe that briefing this emergency procedure prior to takeoff contributed to the positive outcome of this event.

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Original NASA ASRS Text

Title: A P28 lost power after takeoff because a fuel line leak near the left wing sump allowed fuel to be sucked out of the line starving the engine of fuel.

Narrative: Following a normal preflight inspection; taxi; and run-up; I was cleared for takeoff. The takeoff roll was normal. At or slightly after rotation; the engine momentarily hesitated; then resumed normal function. At approximately 100 FT; the engine began running very roughly and producing about 15 percent of the expected power. Further climb was impossible. I declared an emergency and announced my intention to land; landing was uneventful. Time from declaring an emergency to landing was approximately 30 seconds. Post-flight inspection revealed a large (approximately 8 feet long) fuel stain on the left side of the aircraft; on both the left wing and fuselage. Fuel was dripping from the gascolator fuel sump petcock. I suspect that the fuel line near the drain; or the drain itself; suffered a failure. As airspeed increased; the Bernoulli effect overcame the engine fuel pump's ability; and caused loss of power through fuel starvation. I routinely brief for engine failure in takeoff. At this airport; my procedure is to land on the remaining runway if possible; otherwise the other runway; otherwise generally ahead. I firmly believe that briefing this emergency procedure prior to takeoff contributed to the positive outcome of this event.

Data retrieved from NASA's ASRS site as of April 2012 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.