Rans S-17 N6171R accident near Fontana, California

Probable cause

A loss of engine power due to improper construction and inadequate maintenance of the fuel system and engine. Contributing to the accident was the airplane’s inadvertent contact with an unseen guy wire during the landing flare.

NTSB analysis

The pilot was planning to purchase the experimental, light sport airplane from a colleague and was relocating it to his home airport about 40 miles away. He departed, climbed the airplane to 5,500 ft, and flew uneventfully until he was about 20 miles from his destination, at which point, the engine began to lose power, and the airplane began to lose altitude. Despite the pilot's troubleshooting and corrective-action efforts, the engine rpm continued to decrease, and the pilot selected an off-airport landing location on an open construction site. Just before touchdown, the airplane struck an unseen guy wire, and the airplane then descended vertically to the ground. The airplane sustained substantial damage to the wings and fuselage. Postaccident examination revealed multiple fuel system and engine-related deficiencies that were indicative of both improper construction and inadequate maintenance. Although the specific reason for the engine power loss could not be determined, the observed deficiencies, either alone or in combination, could have caused the power loss.

Text from the NTSB. Open the NTSB docket for WPR13LA216 for the full record.