Narrative:

On takeoff roll, aircraft lost 300 RPM (2400 to 2100). Takeoff was aborted safely and problem investigated. Magneto drop check was nominal for this make of aircraft, carburetor heat was not on at the time of incident. Carburetor icing was suspected, but ruled out after discussion with other pilots and mechanics. Possible fuel contamination was then suspected. Tanks were changed from left to right and a normal run-up was performed. All conditions nominal. A normal takeoff (soft field) was attempted and performed successfully. The flight was continued safely to the ultimate destination where the anomaly was reported to maintenance. No water was found during fuel tank sump checks nor was any found when the gascolator was drained. No visible particulates were noted during these checks.

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Original NASA ASRS Text

Title: PA28-161 PLT PERFORMS AN ABORTED TKOF WHEN HE NOTES A 300 RPM DROP ON TKOF. FUEL DRAIN DID NOT INDICATE WATER BUT RPTR SUSPECTS SOME FORM OF FUEL CONTAMINATION. LATER TOOK OFF ON OTHER TANK TO DEST AND RPTED PROBS TO MAINT.

Narrative: ON TKOF ROLL, ACFT LOST 300 RPM (2400 TO 2100). TKOF WAS ABORTED SAFELY AND PROB INVESTIGATED. MAGNETO DROP CHK WAS NOMINAL FOR THIS MAKE OF ACFT, CARB HEAT WAS NOT ON AT THE TIME OF INCIDENT. CARB ICING WAS SUSPECTED, BUT RULED OUT AFTER DISCUSSION WITH OTHER PLTS AND MECHS. POSSIBLE FUEL CONTAMINATION WAS THEN SUSPECTED. TANKS WERE CHANGED FROM L TO R AND A NORMAL RUN-UP WAS PERFORMED. ALL CONDITIONS NOMINAL. A NORMAL TKOF (SOFT FIELD) WAS ATTEMPTED AND PERFORMED SUCCESSFULLY. THE FLT WAS CONTINUED SAFELY TO THE ULTIMATE DEST WHERE THE ANOMALY WAS RPTED TO MAINT. NO WATER WAS FOUND DURING FUEL TANK SUMP CHKS NOR WAS ANY FOUND WHEN THE GASCOLATOR WAS DRAINED. NO VISIBLE PARTICULATES WERE NOTED DURING THESE CHKS.

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.