Amateur-built VARI EZ N830S accident near Ambler, Pennsylvania

Probable cause

Water contamination of the fuel that was not detected during a preflight inspection, which resulted in a total loss of engine power.

NTSB analysis

The private pilot was conducting a personal flight in the experimental, amateur-built airplane. During the initial climb, the engine lost total power when the airplane was about 200 ft above ground level. The airplane descended and impacted trees beyond the departure threshold; the airplane was destroyed. A witness reported hearing the engine "sputter," and another witness reported that the engine sounded like it did not reach full rpm during takeoff. An engine examination revealed that the gascolator and carburetor contained water-contaminated fuel. The examination did not reveal any other preimpact mechanical malfunctions or anomalies that would have precluded normal operation. Due to his injuries, the pilot was unable to recall the events leading up to the accident. Although he indicated that he routinely completed thorough preflight inspections, he likely either did not sample the fuel or did not adequately eliminate water from the fuel before takeoff. Thus, it is likely that the loss of engine power was due to water contamination of the fuel.

Text from the NTSB. Open the NTSB docket for ERA17LA333 for the full record.