N918KG

HISTORY OF FLIGHTOn July 30, 2023, about 10:50 mountain daylight time, a Cessna T206H, N918KG, was substantially damaged when it was involved in an accident near Yellow Pine, Idaho. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

A witness near Cabin Creek USFS Airport (I08), Big Creek Ranger Station, Idaho, observed the pilot attempt to land to the north in gusting wind conditions at the remote, dirt airstrip in a mountain valley. The pilot then aborted the landing and executed a goaround. During the go-around, the airplane appeared to be low, and the witness lost sight of it when it went behind a ridgeline. When the airplane did not reappear after several minutes, the witness became concerned and reported it to local authorities. A search for the airplane was initiated and the wreckage was located shortly thereafter, about 2 miles north of the departure end of runway 2.

Flight data from the onboard avionics revealed that at 1047:52, the engine’s rpm increased from about 1,862 to 2,245 rpm, and the in the next several seconds the airplane started to climb, consistent with a go-around. At the start of the go-around, the airplane’s airspeed was about 73 knots, the vertical speed was about -605 ft per minute (fpm), the pitch attitude was about 1°, and the altitude was about 4,279 ft mean sea level (msl). During the climbout, the airplane’s indicated airspeed decreased to about 55 knots and its pitch attitude increased to about 15–17°. In about the next 2 ½ minutes, the airplane reached a maximum indicated airspeed of about 60 knots. The last complete data point showed the airplane’s airspeed was about 53 knots, the engine rpm was about 2,218, the pitch attitude was about 21°, and the roll angle was about 14° right bank.

During the last few minutes of flight, the flight data showed that the engine was operational, and all engine parameters, including engine rpm, cylinder head temperatures, oil temperature, oil pressure, fuel flow, and fuel quantity, were in the normal operating range. During this time, the engine’s manifold pressure was above the normal operating range but did not exceed the maximum operating limit. From the time the go-around was initiated until the time the flight data ended, the airplane’s average climb rate was about 413 fpm. METEOROLOGICAL INFORMATIONThe nearest weather reporting stations were Lemhi County Airport (SMN), Salmon, Idaho, about 44 miles east; Challis Airport (KLL), Challis, Idaho, about 48 miles southeast; and Mc Call Municipal Airport (MYL), Mc Call, Idaho, about 52 miles westsouthwest. All the stations showed a similar wind pattern on the day of the accident. The wind was calm before 1200 and then, between 1200 and 1300, the wind direction was from the south at 15 to 25 knots. There were no active AIRMETs, SIGMETs, or center weather advisories in the area. Additionally, no PIREPs were reported in the area.

A sounding model for the accident site depicted a near-surface wind about 195° at 5 knots and, at 2,000 ft above ground level (agl), a south wind at 20 knots. The model did not indicate the possibility of low-level wind shear. Light clear air turbulence was indicated about 900 ft agl. WRECKAGE AND IMPACT INFORMATIONThe airplane came to rest near Cabin Creek, on a northeasterly heading, at an elevation of about 5,552 ft msl, in heavily forested, mountainous terrain. Several trees and bushes were cut off near the wreckage. All major structural components of the airplane were observed with the main wreckage.

Postaccident examination of the airplane and engine revealed no evidence of failures or malfunctions that would have precluded normal operation. The engine was able to be manually rotated, and flight control continuity was established. ADDITIONAL INFORMATIONIn 2022, The FAA Safety Team produced a safety enhancement topic on Mountain Flying. The briefing included:

Mountain terrain can be hazardous for GA pilots. Here are some of the ways pilots get into trouble in the mountains.

Poor Planning. Before descending into a mountain airport, look at what your options are for go-arounds and takeoff routes.

Box Canyon. Never fly up a canyon that you have not already flown down so that you know if there is room to turn around. NEVER try to out climb the terrain in ANY airplane. MEDICAL AND PATHOLOGICAL INFORMATIONAn autopsy of the pilot was performed by the Ada County Coroner’s Office in Boise, Idaho, at the request of the Valley County Coroner. According to the autopsy report, the cause of death was multiple blunt force injuries.

The pilot’s medical history included Fuch’s corneal dystrophy (a gradually progressive eye condition that may result in vision disturbances and eye discomfort). His only FAA aviation medical examination was September 5, 2019. He was granted an Authorization for Special Issuance of medical certification in June 2020 for Fuch’s corneal dystrophy; this later was withdrawn for deficient right eye near vision and Fuch’s corneal dystrophy. However, after further evaluation, he was granted another Authorization for Special Issuance in January 2021. His most recent medical certificate was a third-class medical certificate limited by a requirement to wear corrective lenses for distant vision and have glasses for near vision, not valid after September 2021. In September 2021, he completed a BasicMed course and reported completing a BasicMed Comprehensive Medical Examination Checklist.

The pilot’s autopsy also identified cardiovascular disease. There was plaque resulting in about 75% narrowing of the left anterior descending coronary artery, 75% narrowing of the posterior descending coronary artery, 50% narrowing of the right coronary artery, and 50% narrowing of the left circumflex coronary artery. Moderate aortic plaque and bilateral iliac artery aneurysms also were present. The heart was described as enlarged. The remainder of the visual examination of the heart did not identify other significant natural diseases.

Toxicology testing performed at the FAA Forensic Sciences Laboratory detected the following on specimens from the pilot:

Diphenhydramine was detected at 22 ng/mL in the pilot’s cavity blood, and at 225 ng/mL in his urine. Diphenhydramine is a sedating antihistamine medication widely available over the counter in multiple sleep aids and cold and allergy products. Diphenhydramine can result in cognitive and psychomotor slowing and drowsiness and often carries a warning about driving and operating machinery. The FAA states that pilots should not fly within 60 hours of using diphenhydramine, to allow time for it to be cleared from circulation, and regular use is unacceptable. Diphenhydramine may undergo significant postmortem redistribution, and numerical interpretation of diphenhydramine levels measured in cavity blood is unreliable.

Acetaminophen was detected. Acetaminophen (Tylenol) is a non-prescription medication used to treat mild pain and is acceptable for pilots.

Naproxen was detected. Naproxen (Aleve) is a non-prescription medication used to treat pain and inflammation. Naproxen is acceptable for pilots if the underlying condition is acceptable.