What happened
On November 23, 2011, a Piper PA-36-300 was conducting its first crop dusting flight of the day over the Hacienda Piedad Zaruma in Ecuador. The aircraft had departed from Pasaje with a payload of 40 gallons of emulsion and 50 gallons of fuel to treat 8 hectares of banana crops.
The pilot, flying under Visual Flight Rules (VFR), had previously communicated with the Santa Rosa Tower to announce the upcoming activity. While performing the second pass of the fumigation mission, the pilot reported hearing a loud explosion-like sound followed by thick white smoke emanating from both sides of the engine.
Following the sudden loss of power, the pilot attempted to deploy flaps and trim the aircraft; however, the low altitude—approximately 20 meters above the ground—precluded any significant maneuvering. The aircraft entered a stall and impacted the terrain. The pilot was able to evacuate the wreckage unharmed, but the Piper PA-36-300 was destroyed by the forces of impact.
The investigation
The investigating board conducted a detailed examination of the engine and propeller. Laboratory analysis of the Lycoming IO-540-K1G5 engine revealed that the oil suction filter contained approximately 75% of debris from the connecting rod bearing of cylinder number six.
Technical inspections showed that the crankshaft was unable to rotate due to extensive damage caused by the failure of connecting rod number six, which subsequently broke the camshaft into two pieces. The investigation focused on the internal components of the engine to determine the sequence of mechanical failures.