CESSNA 182S — Alcova, WY

What happened

The pilot was conducting a low-altitude pipeline patrol flight in day visual meteorological conditions when the airplane descended and impacted terrain. According to the flight track data, the airplane overflew Casper, Wyoming, and then turned to a southwest heading for about 30 miles until radar contact was lost; the airplane’s altitude was about 600 ft above ground level (agl) and about 950 ft northwest of the accident site.

Postaccident examination of the airplane revealed no evidence of any preaccident mechanical malfunctions or failures that would have precluded normal operation.

A search of archived weather information from Leidos Flight Service and ForeFlight indicated that there were no flight plans or weather briefings requested by the pilot on the day of the accident. It is unknown what weather information, if any, the accident pilot checked or received before departure and through the time of the accident.

The weather forecast information applicable for the accident time indicated an AIRMET TANGO advisory was valid for the accident location and time. Supplemental turbulence information in the form of Graphical Turbulence Guidance (GTG) also indicated light to moderate turbulence for aircraft the size of the accident airplane within 500 to 1,000 ft agl at the time of the accident.

A cold front was identified near the accident site, and mountainous terrain environment, with recorded wind of 20 to 30 knots between the surface and 10,000 ft agl, which made for the potential of low-level wind shear (LLWS) and low-level turbulence. At Casper/Natrona County International Airport (CPR), Casper, Wyoming, recorded wind gusts were as high as 31 knots. These conditions were likely also present above the terrain at the accident site, and it is likely the accident flight encountered light to moderate turbulence and LLWS.

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