MOONEY M20C — Cody, WY

What happened

The two pilots were on a multi-leg cross-country trip in the airplane to visit friends and relatives. Both pilots had current medical certificates, and it could not be determined who was acting as pilot-in-command at the time of the accident. The pilot seated in the right front seat had owned the airplane for over 20 years and had accumulated considerable experience flying it. Neither pilot had an instrument rating.

Postaccident review of meteorological information indicated that at the time of the flight's departure, the departure and arrival airports were reporting visual meteorological conditions; however, the initial segment of the flight required flight over mountainous terrain where instrument meteorological conditions (IMC) and mountain obscuration existed. There was no record of either pilot having obtained an official weather briefing before the flight; however, they were most likely aware of the mountain obscuration, as it would have been visible before takeoff and during the initial stages of the flight.

The airplane was equipped with a panel-mounted GPS receiver that was capable of providing minimum safe altitude information along a user-defined flight plan, but it is unknown if the pilots were using this feature. An iPad, which the pilots reportedly used for navigation, was found in the cockpit; however, impact damage to the device prevented determination of what navigation software was installed. Additionally a sectional chart covering the accident area was on board; however, the chart was found stowed in the rear pocket of the left front seat, indicating that the pilots were not using it during the flight.

Radar and weather data revealed that the airplane entered the clouds shortly after takeoff. The flight track began to waver slightly about 7 minutes after takeoff, likely due to the airplane being hand-flown as it entered IMC. The flight track remained generally on course toward the destination airport as the flight progressed, and there was no indication of an attempt to return to the departure airport. The airplane flew through the mountainous terrain at a fairly consistent altitude about 2,500 ft below the maximum elevation figure of 12,500 ft mean sea level shown on the sectional aeronautical chart for the area and eventually struck the side of a mountain about 430 ft below its summit.

The consistency of the airplane's flight track indicates that the pilots most likely intentionally elected to enter IMC in an effort to fly over the mountainous terrain and into the clearer weather beyond. The airplane's altimeter was set to the correct pressure, and postaccident examination did not reveal any anomalies with the airframe or engine that would have precluded normal operation. The investigation was unable to determine why the pilots elected to fly at an altitude below the maximum elevation for the area.

While both pilots had reported histories of significant cardiovascular disease, autopsies and toxicological analysis did not reveal any findings that would have contributed to the accident. Although ethanol was detected in the right-seat pilot's urine, the levels were not sufficient to have caused impairment.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.