An overheated engine cylinder might explain the power loss in an airplane that crashed in Ogden Canyon on July 12, killing one man and seriously injuring another, a federal investigator said.

However, Verlin B. Tranter of the National Transportation Safety Board in Denver said it isn't known why the cylinder overheated. He said he is waiting for an official report from the maker of the six-cylinder engine, Teledyne Inc. Continental Motors Aircraft Products Division.Floyd Henry Duncan Jr. of Bountiful said the Cessna P210 lost power over the Wasatch Range after he and fellow pilot Floyd Leonard "Buddy" Hatley of Sunset took off from Ogden-Hinckley Airport bound for Flaming Gorge Reservoir.

Duncan, who was at the controls, said he unsuccessfully tried to reach Pineview Reservoir, then turned to fly west through the canyon. The plane hit power lines and crashed into the Ogden River near the canyon's west mouth.

Hatley was killed. Duncan suffered several broken bones and only recently was released from McKay-Dee Hospital.

Tranter said he oversaw disassembly of the air-cooled piston engine at Continental in Mobile, Ala. There was evidence one cylinder was running extremely hot, he said, exploding the fuel rather than burning it properly.

"It's more of a bang than it is a push," Tranter said.

A Continental lawyer in Alabama said the company was not permitted to talk about cases under investigation.