N236AMAviat Aircraft A-1B · 2006

On May 15, 2019, about 1339 Pacific daylight time, an Aviat Aircraft Inc., A1-B airplane, N236AM, was destroyed when it was involved in an accident near Santa Ynez, California. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

A ranch owner reported that the pilot had landed the airplane at his ranch the morning of the accident. The ranch owner stated that, while walking with the pilot from the airplane to the club house, the wind began picking up, and the pilot decided to return home. After walking about halfway back to the airplane (about 100 yards), the pilot sat down on a bench and told the ranch owner that he was “kind of tired today.” A few minutes later, they continued walking to the airplane. The ranch owner then watched the pilot board the airplane, taxi out, and take off. The pilot was destined for Santa Ynez Airport (IZA), Santa Ynez, California, located about 23 miles east of the ranch.

According to local law enforcement personnel, about 2000, concerned friends and family members notified them that the pilot had not returned, and shortly after, the Federal Aviation Administration issued an alert notice. A law enforcement air unit found the airplane wreckage the following morning on steep, rising, mountainous terrain about 8.8 miles northeast of IZA.

Recorded radar data showed a radar target consistent with the accident airplane about 6 miles west of the ranch on a west-northwesterly heading at 4,675 ft mean sea level (msl). The data showed the airplane continue a west-northwesterly heading for about 6 minutes varying between 4,375 and 4,775 ft msl. Subsequently, the airplane turned right to a northwesterly heading. About 20 seconds later, the airplane started descending. The airplane continued a northwesterly heading while descending for about 2 minutes until radar contact was lost. The last recorded radar target was about 0.2 mile south of the accident site at 2,725 ft msl. Figure 1 shows the airplane’s radar track laid over an aerial view of the mountainous terrain and the departure, destination, and accident site locations.

Figure 1. The airplane’s radar track laid over an aerial photograph of the mountainous terrain and the departure, destination, and accident site locations.

The pilot’s logbooks were not found during the investigation.

The airframe, engine, and propeller logbooks were not found during the investigation.

The Geostationary Operational Environmental Satellite17 visible imagery at 1331, 1336, and 1341 showed an extensive layer of clouds spanning east-to-west along the coast obscuring Santa Barbara, California and the departure ranch area, which extended immediately south of IZA, with a broken layer of low stratiform-type clouds that obscured the accident site and the lower terrain west of the site.

A TAF valid from 1100 to 1400 forecast wind from 210° at 8 knots, visibility 6 miles or more, ceiling broken at 800 ft above ground level (agl), and ceiling overcast at 1,500 ft. From 1400 to 2000, the forecast was wind from 240° at 12 knots, visibility 6 miles or more, scattered clouds at 2,500 ft agl, and ceiling overcast at 8,000 ft agl. The TAF was amended at 1102 to a scattered layer of clouds at 800 ft agl and ceiling overcast at 1,500 ft agl. At the time of the accident, AIRMET Sierra was valid for mountain obscuration near the accident site.

The airframe, engine, and propeller logbooks were not found during the investigation.

Examination of the accident site revealed that the airplane had impacted mountainous terrain at an elevation of about 2,700 ft msl and an approximate magnetic heading of 284° (see figure 2 for a photograph showing an aerial view of the accident site). The main wreckage came to rest upright about 30 ft below the initial impact point and was mostly consumed by fire. All the airplane’s major structural components were present at the accident site.

Figure 2. Aerial view of the accident site.

The wreckage exhibited severe thermal fire damage (see figure 3 for a photograph of the wreckage). All the fabric covering was burned and/or melted away from the wing and fuselage structure, except for the outboard left horizontal stabilizer. The right wing remained attached to the airframe, but the left wing was separated from the airframe. Both the left and right wings were severely fire damaged and bent and buckled throughout their spans.

Figure 3. Photograph of the recovered wreckage.

The cockpit instrumentation was separated from the airframe. One gyro was separated from the instrument housing. The gimble exhibited rotational scoring. Flight control continuity was established to all primary flight control surfaces. The control cables were separated in multiple places, consistent with tension overload or being cut by wreckage recovery personnel. The forward and rear control column interconnect was intact and fire damaged. The torque tube remained attached to the elevator control surfaces and extended forward to the cockpit’s rear area.

The engine was separated from the airframe; however, it remained attached to the engine mount structure and exhibited thermal and fire damage. The crankshaft could not be rotated. Borescopic examination of the internal areas of the crankcase and cylinders revealed evidence of heavy corrosion throughout them. All connecting rods, pistons, and valves were intact. The intake and exhaust valves exhibited normal operational signatures. No evidence of preaccident mechanical failures or malfunctions were revealed with the airframe or engine that would have precluded normal operation.

The Santa Barbara County Sheriff-Coroner, Santa Barbara, California, performed an autopsy of the pilot. The pilot's cause of death was multiple traumatic injuries.

The FAA's Forensic Sciences Laboratory performed toxicology testing of specimens from the pilot, which detected 267 (ng/mL, ng/g) zolpidem in the liver, 64 (ng/mL, ng/g) zolpidem in muscle, and atorvastatin in the liver. Zolpidem, is a prescription central nervous system depressant used for the short-term treatment of insomnia. It typically carries a warning to drivers and machinery operators that it may cause drowsiness, prolonged reaction time, dizziness, sleepiness, blurred vision, and reduced alertness, it also may cause next-day psychomotor impairment, including impaired driving. Atorvastatin is a prescription medication used to control cholesterol and is not considered impairing. The pilot’s wife reported that the pilot was taking blood pressure medication and suffered from insomnia.