What happened
Shortly after initiating takeoff for an aerial application flight, the pilot experienced a partial loss of engine power. Unable to maintain altitude or continue the climb, the pilot executed a forced landing in an open field. The descent was abrupt, resulting in a hard impact with the ground. Upon landing, both main landing gear assemblies collapsed under the stress of the impact.
The investigation
Following the accident, investigators conducted a thorough inspection of the aircraft's engine to determine the mechanical cause of the power failure. Examination of the ignition system revealed significant damage. Specifically, both magneto distributor blocks were found to be cracked. Additionally, evidence of carbon streaking was discovered on the magneto leads, suggesting an electrical fault or insulation breakdown within the ignition components.
Findings
The investigation concluded that the partial loss of power was directly linked to the condition of the engine's ignition system. The cracked distributor blocks and carbon streaking on the leads indicated a failure in the magneto assembly, which prevented the engine from producing full power. This mechanical failure necessitated the emergency landing.
Safety message
Regular inspection of ignition components is critical for aerial application aircraft operating under high stress. Early detection of cracks or electrical anomalies in magnetos can prevent in-flight power loss and subsequent accidents.