The Girdwood man who crashed a Piper aircraft into a mountain north of the town’s airport had alcohol in his bloodstream testing at about six times the legal limit for civilian pilots, according to federal investigators.

The crash happened on Aug. 4 outside of Girdwood and took the lives of four people: pilot Charles Weimer, 31; plane owner Karl Erickson, 55; David Osborn, 60 — all of Girdwood — and Paul Wiley, 37, of Arizona.

The four men were on a short sightseeing flight spanning the Girdwood area, “which consists of remote, steep, mountainous terrain,” according to a National Transportation Safety Board preliminary report.

The Piper PA-22-150 crashed about 4:30 p.m. in steep, rocky terrain alongside Goat Mountain near Eagle Glacier, according to the report.

According to witness accounts in the report, the plane was “flying parallel to a mountain ridge before it entered a turn to the north and began a descent. The airplane then disappeared from view, and then they saw a plume of black smoke."

“One witness saw the airplane performing aggressive maneuvers earlier in the flight, and observed the airplane approach a mountain ridge, its nose pitched up and the airplane entered a steep climb before disappearing from view. No witnesses reported hearing any unusual sounds from the accident airplane," the report states.

The medical examiner’s report attributed the pilot’s death to multiple blunt injuries to the neck, chest and abdomen area, but alcohol “may be viewed as a factor contributing to the death.”

The NTSB report featured toxicology results, which showed Weimer’s blood testing positive for ethanol, an intoxicating ingredient found in beer, wine and liquor.

“Ethanol acts as a central nervous system depressant; it impairs judgment, psychomotor functioning, and vigilance," the report states. "Effects of ethanol on aviators are generally well understood; it significantly impairs pilot performance, even at very low levels.”

Weimer’s ethanol levels as high as .252 grams per deciliter. According to the report, people with blood ethanol levels above .15 grams per deciliter “may have significant loss of muscle control and major loss of balance.”

Anything above .20 grams per deciliter and “individuals may experience amnesia or blackouts and double vision,” in addition to “worsening motor coordination and disorientation,” the report said.

According to the report, a close friend of Erickson said he was texting him the day of the crash.

The friend told investigators Erickson “indicated that he and the pilot had been drinking alcoholic beverages, but stated that he would not be flying the airplane and would be a passenger on the accident flight,” according to the report.

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