The pilot reported that during flight, the Piper PA18’s engine lost partial power.
He applied carb heat and adjusted the mixture, but the engine did not respond.
The engine continued to lose power and the pilot made a forced landing on rough terrain near Rushville, Nebraska. During the landing, the right wing hit the ground. The airplane sustained substantial damage to the right wing spar.
The pilot reported that the accident could have been prevented if he had “checked for carb ice sooner.”
He reported that the temperature about the time of the accident was 30° F, and that the dew point was 34° F.
According to the FAA Carburetor Ice Probability Chart, a serious icing probability existed at cruise or climb power.
The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.
Probable Cause: The partial loss of engine power due to the accumulation of carburetor ice, which resulted in a forced landing on rough terrain.
This March 2019 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.