Agricultural Aircraft Forced Landing After Cockpit Fills With Smoke, Engine Fails (N21635)

Incident Details

An agricultural pilot was conducting low-altitude spraying operations over a cornfield, using smoke-generating equipment to mark swath runs. After completing approximately two-thirds of the field, the pilot reported that he "felt heat" and smoke "filled" the cockpit. Simultaneously, the engine lost power. The pilot immediately executed a forced landing to a rough and uneven crop field. According to the pilot, the elapsed time from the initial sensation of heat to ground impact was about 2 to 3 seconds.

Investigation Findings

Examination of the wreckage revealed no evidence of a sustained fire. However, the feeder tube that supplies oil to the smoke generator was found to be burned adjacent to the outside of the right exhaust stack. The smoke generator kit had an FAA-approved Supplemental Type Certificate and had been operated previously without reported problems. A detailed examination of the engine did not determine the reason for the reported loss of power.