Moth Aircraft Corp DH60GM N919DH accident near Cortez, Colorado

Probable cause

A partial loss of engine power due to carburetor ice accumulation, which resulted in a loss of altitude and impact with trees.

NTSB analysis

The pilot reported that, shortly after takeoff, he reduced engine power to about 1,800 rpm and continued along a valley in a shallow climb. As the airplane approached a ridge, he turned the airplane back toward the valley and felt a “subtle sluggishness” of the airplane during the turn. He applied carburetor heat; however, it did not appear to have an effect, and he turned the carburetor heat off after about 20 seconds. The pilot continued toward an area of rising terrain because the engine was running smoothly and, he believed, producing enough power to return to the departure airport. The airplane descended and impacted trees, resulting in substantial damage to the wings, empennage, and fuselage.

The recorded temperature and dew point at the time of the accident were conducive to the accumulation of serious carburetor icing at a glide power setting. Based on the available information, it is likely that the airplane lost partial power due to the accumulation of carburetor ice, which resulted in a gradual descent and impact with terrain.

Text from the NTSB. Open the NTSB docket for CEN19LA260 for the full record.