Primary finding
Probable cause
the pilot's improper planning/decision, including his failure to maintain sufficient altitude/clearance from mountainous terrain to compensate for altitude deviations that resulted from mountain wave/wind conditions. Factors relating to the accident were: the weather/wind conditions, and the proximity of mountainous terrain.
Investigator assessment
Analysis narrative
While in cruise flight at 500 to 1,000 feet above ground level on a cross-country flight, severe turbulence was encountered, and according to the pilot, he was unable to maintain altitude. Subsequently, the airplane collided with trees in mountainous terrain. The pilot walked approximately three miles to the nearest highway. Reportedly, he had received a weather briefing before departure, which provided information that high winds and moderate to severe turbulence could be expected along his entire route of flight.
Source record
Factual narrative
On January 28, 1996, at 1500 mountain standard time, a Boeing B75N1, N69808, collided with trees during cruise flight near Bernal, New Mexico. The private pilot received minor injuries and the aircraft sustained substantial damage. Visual meteorological conditions prevailed for this personal flight operating under Title 14 CFR Part 91 and no flight plan was filed. The flight was en route to Santa Fe, New Mexico, and departed Las Vegas, New Mexico, at 1445, after refueling. According to the pilot, he encountered winds of 35 knots gusting to 45 knots at 500 to 1,000 feet above ground level and could not control altitude. The aircraft was forced into the trees. The pilot said he walked out to the highway which was approximately three miles from the accident site. In his written statement, the pilot said his "briefing indicated very windy conditions along the entire route with a SIGMET for turbulence (moderate to severe)." -