WETMORE, Colo. (AP) — Investigators say a vintage biplane that crashed and killed the pilot in south-central Colorado last year began to slow down and bank before striking some trees and crashing.

A National Transportation Safety Board report dated Thursday quotes a passenger who survived the crash as saying he and the pilot had not spoken in the minutes before the crash.

The report summarizes the investigator’s factual findings but does not establish the cause of the crash.

The 1947 Boeing two-seater crashed on July 3, 2011, near Wetmore in the San Isabel National Forest about 110 miles south of Denver.

The crash killed 50-year-old Sidney Emmert of Oklahoma City. His passenger, Robert Hamilton of Wetmore, was treated at a Colorado Springs hospital and released.

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