An airplane that crashed, killing two brothers, in southwestern Utah broke apart in mid-flight, a federal aviation report said.

The National Transportation Safety Board released a preliminary report into the crash that killed Benjamin and James Timpson of Centennial Park, Ariz. The single engine Piper plane crashed Oct. 26 near Colorado City, Ariz.

According to the NTSB's preliminary report, the airplane was flying from Bountiful, in Davis County, to Colorado City when it experienced an in-flight loss of control, broke up and then crashed into mountainous terrain about 21 miles southeast of Cedar City.

"The airplane was destroyed during the in-flight breakup and post-impact ground fire," it said.

An NTSB investigator looked over the crash scene and noted the "outboard portions of both wings separated from the inbound span of the wings, which remained attached to the fuselage."

"The ailerons were found separated from the wings," the report said. "The entire instrument panel, cockpit and cabin were destroyed by fire, along with several acres of adjacent native vegetation on the mountainside, elevation 6,400 feet mean sea level."

The NTSB said recorded air data showed the plane left Bountiful at 6:15 p.m. on Oct. 29, heading south toward Colorado City's airport. The plane began descending rapidly around 8 p.m., then crashed.

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