On March 23, 1989, an Aeronca 7AC (registration N1790E) was involved in an aviation accident near Catoosa, OK. Investigators recorded the probable cause as: Loss of engine power due to carburetor icing, which occurred under weather conditions conducive to ice formation. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A pilot experienced a complete loss of engine power during level flight and executed an emergency landing on uneven ground, attributing the incident to carburetor icing under conducive weather conditions.
What happened
The aircraft was operating in level flight when the engine ceased producing power. The pilot attempted to restore engine operation but was unsuccessful. Consequently, he was forced to execute an emergency landing on rough terrain.
The investigation
Post-incident analysis focused on the environmental conditions at the time of the event. The reported temperature was 50 degrees Fahrenheit with a dew point of 25 degrees Fahrenheit. These meteorological readings were evaluated against standard carburetor icing charts to determine the likelihood of ice formation within the engine's induction system.
Findings
The investigation determined that the atmospheric conditions were conducive to carburetor icing at both glide and cruise power settings. The pilot attributed the loss of power to this phenomenon. No other mechanical failures or contributing factors were identified in the provided narrative.
Probable cause
Loss of engine power due to carburetor icing, which occurred under weather conditions conducive to ice formation.