What happened
On July 5, 2004, a Cessna 182K, registration PT-DAP, was performing a flight in the Amazon region to support indigenous communities under a health program. The aircraft was traveling between various villages in the Yanomami indigenous reserve. Approximately 10 minutes after departing from Aldeia Ericó, the engine began experiencing intense vibrations, which quickly led to a total loss of power.
The pilot attempted to glide the aircraft toward a suitable landing site. During the descent, the pilot managed to contact another aircraft in the vicinity to communicate the probable impact location. The aircraft struck trees, causing the left wing to detach upon the first impact before the fuselage hit the ground on its back. The aircraft was destroyed. The pilot sustained serious injuries, while the three passengers—two of whom were seated on the floor of the cabin without seatbelably—sustained minor injuries. All occupants were rescued the following day.
The investigation
CENIPA investigators examined the wreckage and the propeller assembly at a certified workshop. The investigation revealed that a pin connecting one of the propeller blades to the hub had fractured. This failure caused the blade to become misaligned, creating the severe vibrations that ultimately led to the engine failure.
Further inspection of the propeller components showed evidence of improper maintenance, including marks left by inappropriate tools and evidence that the pin had been modified using a lathe to reduce its length. Additionally, investigators discovered that the installed propeller part number was not compatible with the aircraft model. The investigation also noted that the aircraft owner failed to provide essential maintenance logs, flight logs, or component control records, which prevented a full review of the aircraft's maintenance history.