N3270FMooney M20F · 1967

On February 8, 2019, about 2010 Pacific standard time, a Mooney M20F airplane, N3270F, was destroyed when it was involved in an accident near Diablo, California. The student pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

Federal Aviation Administration (FAA) radar information indicated that the accident airplane departed Hayward Executive Airport (HWS), Hayward, California, at 2003 and established a northeasterly heading toward the destination airport at an altitude about 2,800 ft mean sea level (msl). The airplane proceeded on this heading and approximate altitude until the final radar return at 2010, in the vicinity of the accident site.

The FAA issued an Alert Notice (ALNOT) for the missing airplane after the pilot did not arrive at his planned destination. The wreckage was located the next day by hikers about 1,000 ft below and 3/4 mile southwest of the summit of Mount Diablo (elevation 3,849 ft msl).

Several state park employees were located on Mount Diablo on the night of the accident. One officer, located at an elevation of about 2,500 ft msl, reported that the weather was foggy and wet. Another officer, located about 2,150 ft msl, reported intermittent rain and wind. The superintendent, who lived on the mountain, heard a low-flying airplane about the time of the accident and stated that the engine sounded loud, and that it was low. The weather windy and cloudy.

A visitor center facility, on top of which was a red light, was located at the summit of Mount Diablo. Additionally, there was a 300-ft-tall tower equipped with obstacle warning lights about 1,450 ft west of the summit.

Review of the pilot's logbook revealed 57.1 total hours of flight experience. The pilot had not received an endorsement from a flight instructor for solo flight at night, nor had he received an endorsement for cross-country flight for the intended route of the accident flight.

The two-seat, low-wing airplane was manufactured in 1967. It was powered by a Lycoming O-360, 180 horsepower engine. No current airframe or engine logbooks were located.

The 1953 automated observation at Buchanan Field Airport (CCR), Concord, California, located about 9 miles north-northwest of the accident site, included wind from 020° at 6 knots, 3 miles visibility in moderate rain and mist, scattered clouds at 600 ft, broken cloud ceiling at 1,300 ft above ground level (agl), overcast cloud ceiling at 2,800 ft agl, temperature 8°C, dew point 6°C, and an altimeter setting of 29.95 inches of mercury.

The 2014 observation at CCR included calm wind, 5 statute miles visibility, clear sky, temperature 11°C, dew point 9°C, and an altimeter setting of 30.29 inches of mercury.

A low-pressure system associated with an occluded front that extended southward along the California coast, and became a cold front extending southwest over the Pacific Ocean, was located just west of the accident site and was responsible for producing an extensive area of clouds and precipitation over the region. No severe weather forecast alerts or SIGMETs were valid in the area at the time of the accident. AIRMET Sierra for mountain obscuration conditions, and AIRMET Zulu for moderate icing in clouds above the freezing level to 17,000 ft msl, were current at the time of the accident. Winds aloft information indicated wind from 150° at 20 knots at the accident airplane’s highest recorded altitude of 2,900 ft msl.

At the time of the accident, the moon was 12° above the horizon at an azimuth of about 267°. The moon phase was a waxing crescent with 16% of its visible disk illuminated.

Leidos Flight Services (LFS) and other vendors utilizing the LFS system had no contact with the accident pilot on the day of the accident.

The two-seat, low-wing airplane was manufactured in 1967. It was powered by a Lycoming O-360, 180 horsepower engine. No current airframe or engine logbooks were located.

The airplane impacted the side of Mount Diablo at an elevation of about 2,846 ft msl. Wreckage debris was scattered about 100 ft from the main wreckage, and all major components of the airplane were contained within the debris field. The first identified point of contact was a large area of disturbed dirt and broken trees and vegetation. Ground scars and flattened vegetation emanated from the initial impact point to the main wreckage. The airplane came to rest upright in heavy vegetation and trees, on a slope of about 30°. There was evidence of a post impact fire that was mostly contained to the cabin area.

The fuselage came to rest on a heading of about 113° magnetic. The left wing remained attached to the fuselage and the right wing was separated from the fuselage but remained with the main wreckage. The empennage was separated from the fuselage about 3 ft from the leading edge of the horizontal stabilizer.

Three feet of the outboard portion of the right wing had separated and was bent about 90°; the leading edge of the wing exhibited aft crushing on the outboard span. The right flap partially separated and was buckled underneath the wing. The right aileron was attached and was wrinkled. The right fuel tank was breached; no fuel was observed in the tank.

The left-wing leading edge exhibited two circular impact damage impressions on the outboard half. The top portion of the wing exhibited a large opening near the wing root and towards the trailing edge. The left flap and aileron remained attached. The left fuel tank was breached, and no fuel remained inside. The left main gear was retracted. The left-wing tip was separated.

The empennage was relatively intact. The vertical stabilizer and rudder were attached to their respective attachment points. The left horizontal stabilizer and elevator were relatively intact; the right horizontal stabilizer sustained impact damaged to the right outboard portion.

Flight control continuity was established following recovery of the wreckage from the site.

The engine remained attached and was bent about 45° to the right of the fuselage heading. The two-bladed propeller separated from the engine. One of the separated blades exhibited leading edge and chordwise paint erosion. The other separated blade was relatively intact. The propeller spinner was crushed aft around the hub.

The engine was examined following recovery from the accident site. Internal continuity was established, and all cylinders exhibited compression when the crankshaft was rotated by hand. The two magnetos produced spark at all of their respective terminal leads. The vacuum pump drive shaft was intact. No anomalies were observed that would have precluded normal engine operation.

The FAA Airplane Flying Handbook states,

Night operations present additional risks that must be identified and assessed. Night flying operations should not be encouraged or attempted, except by pilots that are certificated, current, and proficient in night flying. Prior to attempting night operations, pilots should receive training and be familiar with risks associated with night flight and how they differ from daylight operations. Even for experienced pilots, night operations should only be conducted in unrestricted visibility, favorable winds, both on the surface and aloft, and no turbulence.

The Contra Costa County Coroner’s Division, Martinez, California, conducted an autopsy on the pilot. The examiner determined that the cause of death was “multiple blunt force injuries.”

The FAA Forensic Sciences Laboratory performed toxicological testing on the pilot, which was negative for carbon monoxide, ethanol, and cyanide. 772 ng/mL of Phentermine was detected in the blood and urine specimens.

Phentermine is a prescription substituted amphetamine class anti-obesity medication used for a limited period of time to speed up weight loss. Additionally, this medication may be misused for performance enhancement and relief of fatigue, and also has some abuse potential.