DENVER (AP) – Federal aviation investigators say pilot error probably caused a small-plane crash southeast of Denver that killed two Colorado men in April.

Separately, investigators said they couldn’t find the cause of another small-plane crash, this one in the Colorado mountains in December. That crash also killed two people, one from Texas and one from Alabama.

A National Transportation Safety Report dated Wednesday said the pilot in the April 23 crash attempted “excessive and unsafe maneuvering” in gusty winds in a single-engine CubCrafters Carbon Cub. The report said the winds were a factor in the crash.

The plane went down at Rocky Mountain Airpark, a housing development with two grass airstrips.

The NTSB said a cellphone video and a witness indicated the plane climbed steeply to about 150 or 200 feet, leveled off and appeared to be motionless before the right wing dropped and the plane spun to the ground.

Witnesses said the pilot had performed a similar maneuver successfully a day earlier.

Authorities identified the pilot as Pete Vinton, 49, and his passenger as David McIntosh, 47, both of Parker. They were the only people aboard.

The other plane crashed while approaching the Eagle County Airport in Gypsum after taking off from Pueblo on Dec. 15.

The pilot was Barton Harris, 67, of Brownwood, Texas. The passenger was Jerry Hoggatt, 73, of Pelham, Ala. The NTSB said both men had pilot’s licenses. They were the only people aboard.

An NTSB report dated Nov. 17 said investigators found no evidence of pre-crash mechanical problems in the twin-engine Beech B60.

The report said the weather was conducive to ice forming on aircraft surfaces. Skies were overcast, with reduced visibility and snow showers in the area.

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