Amateur-built EPIC LT N603JS accident near San Saba, Texas

Probable cause

The improper installation of flexible fuel lines, which resulted in a partial collapse of the inner wall of the fuel lines and a subsequent a loss of engine power due to fuel starvation.

NTSB analysis

The pilot reported that the experimental, amateur-built airplane was in cruise climb when he noticed a gradual loss of fuel pressure, so he diverted to a nearby airport. The engine fuel pressure continued to drop, and the engine then lost total power. The airplane landed hard on the runway, which resulted in substantial damage to the composite wing structure and breached both wing fuel tanks. An examination of the engine revealed no defects or anomalies that would have precluded normal operation. An examination of the steel-braided flexible fuel lines removed from the electric fuel boost pump showed that two of the lines were installed twisted and that one of the lines was kinked and installed with a bend radius tighter than specified. The improper installation of the fuel lines caused a permanent set in the steel braid and a subsequent partial collapse of the inner wall of the fuel lines, which resulted in the partial blockage of fuel flow through the line and a subsequent loss of engine power due to fuel starvation.

Text from the NTSB. Open the NTSB docket for CEN12FA561 for the full record.