Incident Overview
On December 23, 2018, at approximately 1510 mountain standard time, a Cessna 182G, registration N3120S, was substantially damaged during an accident near Norwood, Colorado. The private pilot, who was the sole occupant, was not injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Flight and Weather Conditions
The pilot reported that he was flying south of Telluride, Colorado, over the San Juan mountain range, which lies within the San Juan National Forest. Weather conditions at the time were described as clear visibility, cold temperatures, no visible moisture, and a few scattered clouds. While descending, the pilot observed what he termed "backlit ice crystals" for a brief period and noted no airframe icing.
Carburetor Heat Use and Power Loss
During the flight, the pilot cycled through full, partial, and no carburetor heat settings while monitoring the carburetor temperature gauge. The gauge indicated a normal range during operations with partial and full carburetor heat. The pilot intended to perform a straight-in approach to his private airstrip, landing to the northeast. He initially selected partial carburetor heat but turned it off before landing, as was his routine to avoid drawing unfiltered air into the engine on a dirt runway. During the approach, the airplane drifted to the west, prompting the pilot to execute a go-around. He first advanced the engine power slightly, but the engine did not respond. He then applied full power, still with no engine response.
Maneuver and Impact
With the engine unresponsive, the pilot made a steep right turn and applied right rudder to direct the airplane onto the dry dirt runway and avoid trees. He was uncertain whether the airplane stalled, but the right-wing tip contacted the ground. The airplane then "pancaked" onto the runway, causing damage to the nose landing gear, the propeller, and wrinkles in the skins of both wings. Propeller impact marks were evident on the dirt before the airplane came to rest on the runway. The pilot shut down the engine and exited without further incident.
Damage Assessment
The airplane sustained substantial damage to the fuselage and both wings. The pilot later reported that he did not clear the carburetor "adequately" during his straight-in approach and acknowledged that it was possible the carburetor had "iced up." According to the Federal Aviation Administration Special Airworthiness Information Bulletin CE-09-35 Carburetor Icing Prevention, the weather conditions at the time of the accident were just outside the parameters conducive to carburetor icing at glide and cruise power settings.
Pilot Actions
After the accident, the pilot stated that he had not sufficiently cleared the carburetor. He noted that carburetor ice might have been the cause of the power loss. The pilot had used various carburetor heat settings during the flight and had monitored the carburetor temperature gauge, which showed normal indications when heat was applied. The decision to turn off carburetor heat before landing was based on his standard practice for dirt runway operations.