NTSB Factual Report

On March 23, 1995, about 1952 hours Pacific standard time, a Beech 35-C33, N15LT, collided with mountainous terrain about 4 miles south of Tom's Place, California. The certificated commercial pilot and two passengers received fatal injuries. The airplane was destroyed by impact forces. The airplane was being operated as a personal flight by the pilot/owner. The airplane departed the Van Nuys Airport, Van Nuys, California, about 1800 hours PST. The airplane was destined for Mammoth Lakes, California.

The accident airplane was based in Torrance, California. About 1530 hours on the day of the accident, the pilot told a friend, who is an airline pilot, at the Torrance Airport that he intended to fly to Mammoth Lakes, California. The airline pilot indicated to the Safety Board that he was concerned with the accident pilot's statement since he was aware of the weather conditions en route to Mammoth Lakes. According to the airline pilot witness, the pilot read his facial expression and informed him he had checked the weather. The airline pilot said he then warned the accident pilot "of possible lingering build ups and turbulence over the mountains." The accident pilot responded that "he wasn't too concerned and that he had checked weather." The airline pilot assumed the accident pilot was planning to leave immediately and conduct the flight during daylight.

The accident pilot then departed the Torrance Municipal Airport and flew to the Van Nuys Airport where he picked up two passengers. About 1800 hours, the pilot departed Van Nuys destined for Mammoth Lakes.

At 1955 hours, an off-duty California Highway Patrol officer was outside his residence, which is located about 1 nautical mile east of the accident site. At the time, light snow was falling and low clouds obscured the mountain tops. His attention was diverted to the sound of a small aircraft flying west of his location, between his residence and Wheeler Crest. He indicated that he heard a thud, and at the same time the sound of the aircraft ceased. At 2004 hours, he reported the incident to his communications center.

Another pilot departed via automobile from the Los Angeles basin for Mammoth Lakes about 1330 hours and arrived at about 1830. The pilot reported gusting winds and mountain tops obscured with clouds north of Bishop, California. The pilot also reported he could see clouds and/or snow rolling off the eastern slopes of the Sierras, evident of down drafts. About 1815 hours, the pilot drove past the Mammoth Lakes Airport. Snow was falling, requiring the use of tire chains. The pilot reported that the falling snow obscured his vision and that he could not see the runway lights on the west end of the airport from highway 395.

Mono County Sheriff deputies, based about 1 mile north of the Mammoth Lakes Airport, told Safety Board investigators that the weather was bad enough to cause the scheduled commuter air service to divert to the Bishop Airport located about 23 miles south of Mammoth Lakes.

The airplane was reported missing by concerned family members on March 25, 1995. The Civil Air Patrol initiated search and rescue (SAR) operations using radar data provided by the Federal Aviation Administration (FAA). According to the FAA radar data, the last radar return associated with the accident airplane was at 37 degrees, 20 minutes and 27 seconds north latitude, and 118 degrees, 25 minutes and 31 seconds west longitude, at 10,400 feet above mean sea level (msl).

The airplane was located about 15 miles northwest of the last radar return on March 30, 1995, at coordinates 37-30-47 north latitude and 118-39-50 West longitude, at 9,910 feet above msl on Wheeler Crest. Ground parties from the Mono County Sheriff identified the airplane from a data plate on the airplane's tail.

Pilot Information

The pilot held a commercial pilot certificate which was issued on March 11, 1992, with a rotorcraft-helicopter rating. Additionally, the pilot held a private pilot certificate which was issued on August 4, 1978, with a single engine airplane rating. An airplane instrument rating issued to the pilot on March 7, 1991.

The most recent second class medical certificate was issued to the pilot on October 27, 1994, and contained the limitation that correcting lenses must be worn while exercising the privileges of his airman certificate.

No personal flight records were located for the pilot, and the aeronautical experience listed in this report was obtained from a review of the pilot's FAA records on file in the Airman and Medical Records Center located in Oklahoma City. In addition, information was obtained from a review of records depicting use of another airplane in which the pilot was a part owner.

The pilot was a medical doctor and was employed as an anesthesiologist.

Aircraft Information

The airplane was manufactured on March 26, 1965. According to the manufacturer, the airplane was not equipped with any deicing equipment. Review of a photograph taken before the accident revealed the airplane was not modified with deicing equipment. There were no rubber boots installed on the leading edges of the wings, or the vertical or horizontal tail surfaces.

According to performance data supplied by the airframe manufacturer, the accident airplane should have been capable of a 420-foot-per-minute climb at maximum gross weight at a pressure altitude of 10,400 feet at 19 degrees Fahrenheit.

No maintenance records were found for the airplane. During the investigation it was determined an annual inspection was performed on the airplane in May, 1994, by an FAA certified airframe and powerplant mechanic, who held an inspection authorization.

Meteorological Information

The closest official weather observation station was an automated weather observing system (AWOS) located in Bishop, California. The station is located 16.6 nautical miles east-southeast of the accident site. The elevation of the weather observation station is 4,110 feet msl.

At 2045 hours, a surface observation was reporting in part: sky condition and ceiling, 6,000 scattered; 8,500 feet overcast; visibility, 10 miles; temperature, 38 degrees Fahrenheit; dew point, 22 degrees Fahrenheit; winds, 300 degrees at 6 knots; altimeter, 29.77 inches of Hg.

The nautical data for the accident site indicates sunset was at 1818 hours and the end of evening twilight was at 1844 hours. At the time of the accident, the sun was -19.2 degrees below the horizon.

There were several weather advisories pertinent to aircraft with limited capabilities (AIRMET) and several weather advisories that posed hazards to all aircraft (SIGMET) that were pertinent to the accident airplane's route of flight. The AIRMET's and SIGMET's were published and were available to the public. The AIRMET's and SIGMET's covered weather phenomena associated with mountain obscuration, moderate and severe turbulence, low level wind shear, precipitation, icing and freezing levels, and instrument meteorological conditions.

The Safety Board conducted a meteorological study concerning the weather information pertinent to the accident. The study lists the pertinent AIRMETS and SIGMETS, and is attached to this report.

Wreckage and Impact Information

The accident site was on a 70-degree slope with chest-deep snow. A debris field was oriented in a north-south direction. The airplane was buried in snow and not all of the wreckage was located or recovered. Terrain slope, snow depth, and weather conditions impeded the investigation and a complete on-scene examination was not possible.

The outboard portion of the left wing and aileron were found several thousand feet below the accident site at the 7,800 elevation. The control cables were no longer attached. The internal structure of the wing exhibited tears in the metal ribs where the cables pass. The thickness of the tears appeared the same as the thickness of the control cables.

Other portions of the wreckage were examined by the Mono County Sheriff's Office during county SAR operations on March 30, 1995, and later on May 16, 1995. According to the sheriff's report, the wreckage was scattered several hundred yards across the eastern slope of Wheeler Ridge [Wheeler Crest].

The fuselage was destroyed. The empennage was found hanging on a steep slope supported by the flight control cables that were traced back to the remains of the cockpit. Pieces of the aircraft interior, a wing flap, a tire, and baggage were found in a chute in an avalanche path.

Examination of photographs and video tapes taken by the Sheriff's department revealed the engine had separated from the mounts and came to rest on a ledge south of the fuselage. Five of the six engine cylinders had damage to the cylinder heads. The number 6 cylinder head was missing. The numbers 2, 3, 4, and 5 cylinder heads were damaged to the extent the rocker arms and covers were missing, exposing the intake and exhaust valves and springs. The propeller flange on the crankshaft appeared fractured.

Review of the Sheriff's SAR video revealed the propeller came to rest in close vicinity to the engine. The propeller was partially covered by snow. One of the blades was visible and exhibited twisting and "S" bending.

The wreckage was recovered from the accident site in June, 1995, and transported to a salvage yard in Santa Paula, California. The recovered wreckage was examined on June 21, 1995. During the examination it was noted that the airplane's propeller and engine were missing. The flap actuator was measured and found extended 1.7 inches. According to the airframe manufacturer, the measurement corresponded to a zero degree flap extension or flaps "up" condition.

The elevator trim system was damaged. The actuator was measured and found extended 1-inch, which corresponds to a 10-degree tab up condition. According to the manufacturer, the elevator trim tab measurement represents the tab up limit for the airplane.

Medical and Pathological Information

Post mortem examinations were conducted by the Mono County Sheriff's/Coroner's Office on May 17, 1995, with specimens from the pilot retained for toxicological examination.

The toxicological examination was conducted by the Department of Defense, Armed Forces Institute of Pathology, under contract with the FAA. The results of the toxicological analysis were positive for meperidine at a level of 0.3 mg/kg. According to the FAA Civil Aero Medical Institute, use of this narcotic analgesic while piloting an airplane is in contravention to FAA regulations.

Additional Information

Wreckage Release

The Safety Board did not take custody of, or retain any wreckage during the investigation. The wreckage was left in the care and custody of the aircraft salvager.

NTSB Probable Cause

the pilot's decisions to initially attempt and then continue flight into known forecast and observed adverse weather. Factors in the accident were: the pilot's inadequate preflight planning and his use of a drug.