LAX97FA334

The non-instrument rated pilot departed California on a business flight to a South Dakota destination. No flight plan was filed. Radar flight following service was terminated as the pilot approached the western slopes of the Sierra Nevada Mountains, and there were no further radar contacts or voice communications with the pilot. The pilot did not request any en route weather briefings from FAA flight service stations, and his route of flight over the mountains to the accident site was not determined. Instrument meteorological conditions including multiple cloud layers and rain showers existed in the vicinity of the accident site. Additionally, between 0830 and 0900, National Climatic Data Center visible and infrared spectrum satellite imagery revealed an area of rapidly developing cumulonimbus clouds at the site. On May 18, 1998, the wreckage was located scattered over a distance of 0.64 miles, about 26 miles south of the pilot's intended direct route of flight. The engine, wings, flaps, ailerons, elevators and empennage were found separated from the fuselage, along with a handheld GPS receiver. Acquaintances of the pilot reported he kept accurate flight records. The pilot's logbook contained several 'pilot-in-command' entries indicating that cross-country business flights had been performed in actual instrument weather conditions while navigating using a GPS receiver. No safety pilot or CFI was listed as accompanying the pilot during these flights. About 1.5 days prior to the accident the pilot was treated for a periodontal infection. An antibiotic and narcotic pain reliever was prescribed, and partially empty containers of these drugs were found in the wreckage. Insufficient specimens remained to perform an autopsy or toxicological tests.

History of flight

On July 23, 1997, at an undetermined time after 0825 hours Pacific daylight time, a Navion G, N2429T, owned and operated by the pilot, experienced an in-flight structural failure and crashed about 25 nautical miles (nmi) southeast of Gabbs, Nevada. Between 0800 and 0850, multiple cloud layers and rain showers existed in the vicinity of the accident site over the unpopulated, high desert terrain. The airplane was destroyed, and the non-instrument rated private pilot and passenger were fatally injured. The flight originated about 0655 from the Reid-Hillview Airport in San Jose, California. The pilot's intended destination was the Bob Wiley Field in Winner, South Dakota.

The pilot's wife provided the National Transportation Safety Board with a copy of her husband's computerized flight plan log sheet. The pilot did not file his flight plan with the Federal Aviation Administration (FAA). The log sheet indicated that upon departure the pilot planed to initially fly along a magnetic course of 047 degrees for 167 nmi until reaching the Hawthorne Airport, Hawthorne, Nevada. The pilot then planned to proceed on a course of 042 degrees for the next 200 nmi. The projected ground speed for the first two legs of flight was 187 knots. All of the flight legs were indicated as direct routes. No airways were listed.

After takeoff, the pilot requested and received radar flight following service from the FAA's Oakland, California Air Route Traffic Control Center (ARTCC). The FAA reported that the airplane's transponder signal was received intermittently. The FAA was not able to adequately track the target, and radar service was terminated.

According to the California Wing of the Civil Air Patrol, the airplane was last recorded on radar at 0752:02 when located at 38 degrees 01 minute 23 seconds north latitude, by 119 degrees 41 minutes 41 seconds west longitude. At this time the eastbound airplane was approaching the western slopes of the Sierra Nevada Mountains. Minutes earlier, the pilot had reported to the FAA that he was climbing to 11,500 feet mean sea level (msl).

On May 18, 1998, the airplane wreckage was discovered by cowboys in hilly terrain to the east of the Sierra Nevada mountains. The accident site was located about 47 nmi east-northeast (074 degrees magnetic) from the Hawthorne Airport, and approximately 26 miles southeast of the pilot's flight planned course.

Personnel information

The pilot's flight time information contained in this report was obtained from several sources including data which the pilot submitted to the FAA in his December, 1996, application for a third-class aviation medical certificate, from acquaintances of the pilot, and from remnants of the pilot's personal flight record logbook found at the crash site. Employees at Gavillan Aviation in Hollister, California, reported that the pilot accurately and meticulously recorded his flying activities.

On March 18, 1996, the pilot was issued a Private Pilot certificate. Between May and July, 1996, the pilot's logbook recorded five business related cross-country flights during which 12.2 hours were logged in actual instrument weather conditions. The flights were listed in the logbook's "pilot-in-command" column, and no safety pilot or certified flight instructor was listed as being in the airplane. In one of the flight entries the notation "GPS" was written in the "Actual Instrument" column.

The pilot's logbook also indicated that within 90-days of the accident he had flown his airplane about 52 hours. No instrument flight hours were recorded during this period.

Aircraft information

A partial photocopy of the airplane's maintenance records was obtained and reviewed from Gavillan Aviation. In pertinent part, the records indicated that on June 25, 1997, an annual inspection was completed on the airplane, and the Hobbs meter registered 0.0 hours. The mechanic who performed the inspection verbally acknowledged that the inspection was actually completed a few days earlier, likely around June 18. No evidence was located of any outstanding maintenance squawks. According to Gavillan's owner, during the inspection the airplane's oxygen tank was serviced and completely filled.

No original records were provided for the Safety Board's review. The airplane's total time was estimated, and it is based upon the mechanic's recollection.

Meteorological information

The nearest aviation weather observation station to the accident site is located at the Tonopah Airport, Tonopah, Nevada. The airport is located about 38 nmi east-southeast (121 degrees magnetic) from the accident site, and its elevation is 5,426 feet msl.

At 0800, a special weather observation was taken at the Tonopah Airport. Although the rain showers which occurred the previous hour had ended, some showers continued to be noted in the vicinity of the airport. The sky condition was reported as follows: few clouds at 400 feet above ground level (agl); scattered clouds at 2,700 feet agl; and a broken ceiling at 10,000 feet agl. The temperature and dew point were both 15 degrees Centigrade. The prevailing visibility was 12 miles and was lower in southwesterly to northerly directions (toward the accident site area).

At 0850, the sky condition was reported as follows: few clouds at 600 feet agl; scattered clouds at 2,000 feet agl; and a broken ceiling at 10,000 feet agl. Towering cumulus clouds were observed in all quadrants. The temperature and dew point were 18 and 16 degrees Centigrade, respectively. The surface visibility was 25 miles.

Satellite images in the infrared and visible spectrum were received from the National Climatic Data Center and reviewed by a Safety Board staff meteorologist. At 0830 and 0900, a rapidly developing area of cumulonimbus clouds was noted at the location of the accident site. (See attached reports.)

Communication

The FAA's Western-Pacific Quality Assurance management reported that no preflight or in-flight communications occurred between the pilot and any flight service station. Also, a search of FAA facilities did not reveal evidence that any air-to-ground communications occurred with the pilot while passing over or east of the Sierra Nevada Mountains. No evidence of an emergency locator signal (ELT) was received.

Wreckage and impact information

The engine assembly, wings, flaps, ailerons, and empennage were found separated from each other and from the fuselage. Wreckage was observed scattered over elevations between 5,400 and 5,700 feet msl. The entire airplane structure, including all flight control surfaces, was located at the accident site. There was no evidence of fire.

Along the wreckage distribution path, the first piece of wreckage located was a piece of left elevator-to-stabilizer fairing material. This was located at global positioning satellite (GPS) coordinates of 38 degrees 32.223 minutes north latitude, by 117 degrees 37.962 minutes west longitude. The elevators, tail, wings, and the main wreckage were located between the fairing material and the engine, which was located at 38 degrees 31.662 minutes north latitude, by 117 degrees 37.559 minutes west longitude. The distance and magnetic course between the first and last pieces of wreckage was approximately 0.64 nmi and 136 degrees. (See the Wreckage Diagram for additional information.)

An impact-damaged (destroyed) handheld type of GPS receiver was observed in the wreckage. It was found along with its two suction cup attachment fixtures next to the cockpit.

An oxygen cylinder, along with several feet of plastic tubing, and several nasal cannulas were found in the wreckage area. One cannula was observed in an unopened package, and another was without packaging material.

Medical and pathological information

The two occupants were found, with their seat belts attached, in the cockpit's front seats. The