N732MVCessna T210M · 1976

On September 30, 2018, about 0837 mountain daylight time, a Cessna 210M airplane, N732MV, was destroyed when it was involved in an accident near Silver City, Idaho. The pilot and the two passengers were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The flight originated from Sunrise Skypark Airport, Marsing, Idaho, about 0810 and was destined for Murphy Airport, Murphy, Idaho. The airplane did not have a discrete transponder code; therefore, primary targets from flight track data covering the area and time surrounding the accident were reviewed.

From 0824:24 to 0827:00, a target was moving to the south direction at altitudes between 3,200 and 3,400 ft mean sea level (msl) at an average ground speed of 131 knots. The target was lost at 0827:00 and reappeared at 0831:12 heading south at a position consistent with radar returns being blocked by hilly terrain. The track appeared to be following a road.

From 0831:12 to 0835:00, the returns showed the airplane continuing to move on a southerly track, climbing from about 4,700 to 6,600 ft msl. The last three radar returns showed that the airplane’s altitude above the ground decreased as the terrain rose; at 0834:24, the airplane was about 825 ft above ground level, and by 0835:00 it was about 150 ft above ground level. During this time, the airspeed decreased from 90 kts calibrated airspeed (KCAS) to about 68 KCAS. The last target showed the airplane about 1,950 ft west and 15.5 nm east of the wreckage, which was found near the bottom of a valley. The emergency locator beacon activated at 0836; therefore, it is likely the accident occurred about that time.

Two witnesses located about 1 mile west of the accident site reported that they saw a white airplane flying south and that it appeared to be flying along a north-south oriented ditch or dry river bed and that they then saw it cross over an east-west oriented hill. Shortly after, they saw a plume of smoke on the other side of the hill.

At the time of the pilot’s last medical examination, he reported having type 2 diabetes, high blood pressure, high cholesterol, and hypothyroidism. He was issued a special issuance, third-class medical certificate with the limitation that he must have glasses available for near vision and that stated, "Not valid for any class after 12/31/2017. Not valid outside the borders of the United States." The pilot completed the BasicMed educational course and obtained a BasicMed physician attestation in December 2017.

The airplane’s weight and balance were calculated based on the airplane's empty weight and the pilot’s and two passenger’s reported weights. The airplane’s gross weight at the time of the accident was estimated to be about 3,900 lbs, which was about 100 lbs over its maximum allowable gross weight. The calculations also showed that the airplane had a more forward center of gravity.

The airplane's Pilot's Operating Handbook provides stall speeds at the airplane's maximum gross weight. For an airplane operating at the maximum gross weight and with a forward center of gravity, the airplane's stall speed with 10° of flaps was 68 KCAS at 0° bank; 73 KCAS at 30° of bank; and 96 KCAS at 60° of bank.

equated to about 100 lbs over the maximum gross weight of the airplane, 3,800 lbs, with a more forward center of gravity. The detailed computations are appended to this report.

A friend of the pilot was notified of the accident shortly after it occurred and flew out to the accident location. He reported that, while maneuvering about 1 mile east of the accident site at 6,500 ft msl, his onboard weather system displayed that the wind was from the southwest at 38 knots. A High-Resolution Rapid Refresh model for 0900 in the area surrounding the accident indicated a surface wind from 245° at 15 knots. The wind speed increased to 25 knots by 5,700 ft msl and the wind speed remained between 25 and 35 knots from 5,700 through 14,000 ft msl. The model indicated a chance of light-to-moderate, low-level wind shear in between the surface and 6,000 ft msl. A chance of light-to-moderate, clear air turbulence existed in several layers between the surface and 12,500 ft msl.

The airplane’s weight and balance were calculated based on the airplane's empty weight and the pilot’s and two passenger’s reported weights. The airplane’s gross weight at the time of the accident was estimated to be about 3,900 lbs, which was about 100 lbs over its maximum allowable gross weight. The calculations also showed that the airplane had a more forward center of gravity.

The airplane's Pilot's Operating Handbook provides stall speeds at the airplane's maximum gross weight. For an airplane operating at the maximum gross weight and with a forward center of gravity, the airplane's stall speed with 10° of flaps was 68 KCAS at 0° bank; 73 KCAS at 30° of bank; and 96 KCAS at 60° of bank.

equated to about 100 lbs over the maximum gross weight of the airplane, 3,800 lbs, with a more forward center of gravity. The detailed computations are appended to this report.

The wreckage was located at 6,655 ft msl near the bottom of a north-south oriented valley. The mountains to the immediate east peaked about 6,975 ft msl and those to the south about 6,800 ft msl. The wreckage debris field from the initial impact point to the last found piece of wreckage was about 379 ft extending from south to north. The first identified point of contact with terrain consisted of ground scars and a fragment of the left-wing red navigation light lens, consistent with the tip of the left-wing impacting terrain first. The wreckage lay along a heading of 345°.

The fuel selector was found in the right tank position. The landing gear were found in the up position. The flap actuator was measured to be about 1.8 inches (10° of flaps). Elevator continuity was established from the control columns to the bellcrank, which connected to the elevator arm assembly. The elevator trim was neutral. The aileron returns and right aileron direct cable exhibited tension overload separations in the cabin. All other cables, turnbuckles, and bellcranks remained intact.

Examination of the engine revealed that the case exhibited impact damage. All six cylinders remained attached to the engine crankcase. The propeller, right magneto, alternator, vacuum pump, and throttle and metering assembly were separated from the engine. The cylinders were examined using a borescope, and no anomalies were noted. The engine crankshaft was manually rotated at the engine-driven fuel pump, which exhibited extensive thermal and impact damage. Rotational continuity was established throughout the engine and valve train. Thumb compression and suction were obtained on all six cylinders. The drive was rotated by hand, and no binding was noted. No spark was observed from the primary ignition leads when rotated. The distributor cap was removed, and all the internal components were thermally destroyed. All the spark plugs exhibited normal wear.

The drive coupling remained intact, but it could not be manually rotated. The fuel pump was disassembled, and it exhibited extensive thermal damage. The turbocharger was manually rotated, and it exhibited rotational scoring.

Two of the propeller blades had separated from the hub. All three propeller blades exhibited chordwise scratches. Two of the blades exhibited S-type bending. The blade that remained in the propeller hub exhibited forward bending.

An autopsy was performed by the Owyhee County Coroner's Office, Marsing, Idaho. The cause of death was blunt force trauma. The examination was limited by the extent of injury, but no significant natural disease was identified.

Toxicology testing performed by the Federal Aviation Administration's Bioaeronautical Science Laboratory did not detect any tested-for substances in muscle. Further testing detected quinine and loratadine in liver tissue but no buprenorphine. However, the liver was significantly thermally damaged.

Toxicology testing performed on specimens from the pilot by NMS Labs detected caffeine; quinine; loratadine and its metabolite descarboethoxloratidine, which is a nonsedating over-the-counter medication for heartburn and colds; and buprenorphine (11 ng/gm) and its metabolite norbuprenorphine (22 ng/gm). Buprenorphine, which is a controlled substance, is used to treat severe pain. Buprenorphine carries a warning from the Federal Drug Administration that it “may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery).” Further, opiates cause, in part, sedation, alterations in cognitive and sensory efficiency, respiratory depression, nausea, vomiting, headache, and sleep and concentration disorders.