MOAB — The National Transportation Safety Board is blaming the pilot of a single-engine plane that crashed in Canyonlands National Park last year, killing two men.

In a final report on the May 30 crash, the NTSB determined the cause of the crash that killed John W. Keys III, 66, and Gary Kramer, 49, was "the pilot's failure to maintain terrain clearance while maneuvering at low altitude in a narrow canyon. Contributing to the accident was the mountainous terrain."

The NTSB said Keys was piloting the Cessna 172 on a sightseeing tour of the Four Corners area. About two hours into the flight, authorities said the pilot reported to another pilot that he was at the confluence of the Green and Colorado rivers. Nothing else was heard.

A hiker in the area saw the plane, which appeared to be below the rim of the canyon, in a steep bank before it went out of sight, the NTSB report said. The hiker later came upon the plane's wreckage.

— Ben Winslow