Bellanca 17 31 N28119 accident near Salt Lake City, Utah

Probable cause

The failure of the right main landing gear extension spring to maintain adequate pressure, which allowed the landing gear to collapse during the landing roll.

NTSB analysis

The pilot reported that, during the approach, he conducted his usual prelanding checklist, which included verifying the landing gear position and indicator lights four separate times. He conducted an uneventful touchdown; however, during the landing roll, the right main landing gear collapsed. Postaccident examination of the landing gear revealed that the right main landing gear extension spring appeared to be compressed, and, when tested, it only produced 19 to 20 pounds of pressure. It is likely that this reduced pressure was not sufficient to maintain the extension of the right main landing gear. The nose and left main landing gear extension springs were also tested, and they produced about 40 pounds of pressure. The pilot reported that three new springs, all of which produced 44 pounds of pressure, were subsequently installed on the airplane, and no further landing gear system anomalies were reported after flight testing.

Text from the NTSB. Open the NTSB docket for WPR14LA142 for the full record.