The Boulder County Sheriff's Department says the glider crashed on Gold Hill Road at about 1 p.m. Thursday.
The pilot was being treated at a Boulder hospital for a possible back injury. A passenger was treated and released.
Deputies say it appears the glider entered a downdraft and lost elevation, and when the pilot tried to land in a field, one wing struck power lines, causing the crash.
The Federal Aviation Administration and the National Transportation Safety Board are investigating.
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