Amateur-built 1600R N827WS accident near Marshall, Michigan

Probable cause

Maintenance personnel’s improper installation of an improperly sized clamp on the fuel supply line, which allowed air to enter the supply line, a subsequent loss of engine power, and a forced landing.

NTSB analysis

The pilot departed from a campground area in the single-engine experimental airplane. During the airplane’s initial climb, the engine lost power and the pilot made a forced landing into a cornfield, which substantially damaged both wing struts.

Postaccident examination of the engine revealed a loose fuel supply line to the inlet fitting of the vacuum-driven fuel pump. Although the clamp on the inlet fitting was tightened to its maximum clamping position, it was not the correct size, and the fuel supply line was still loose in the fitting. Thus, it is likely that maintenance personnel did not ensure an airtight fitting with a properly sized clamp, which allowed air to enter the fuel supply line and resulted in a loss of engine power.

Text from the NTSB. Open the NTSB docket for CEN20LA216 for the full record.