What happened
On July 9, 2001, a Cessna T210N, registration PT-OFU, was conducting a private flight from São Félix do Xingu, PA, to Gurupi, TO, carrying one pilot and four passengers. While cruising at 11,500 feet near Redenção, PA, the aircraft experienced a propeller overspeed and a substantial loss of engine power.
Following the engine malfunction, the pilot attempted several procedures but was unable to stabilize the engine, leading to the decision to shut it down and perform an emergency landing. The pilot initially intended to reach an airfield in Redenção, but realized the aircraft lacked sufficient altitude to reach the destination. He subsequently selected a farm strip for the landing. During the approach, a passenger alerted the pilot to cattle on the runway, prompting a go-around. During this maneuver, the pilot retracted the flaps to 10 degrees and prepared to land on a shorter, adjacent strip. The aircraft sustained substantial damage to the engine and wings during the landing.
The investigation
CENIPA investigators examined the propeller governor and found significant internal damage. The investigation revealed that the auxiliary pump's gear was damaged, and the main body of the governor showed damage caused by debris from a bearing that had likely undergone excessive stress. The auxiliary pump's gear shaft was found fused to the cover, suggesting overheating, and exhibited severe wear. Additionally, the weight counterweight heels showed excessive wear, indicating improper maintenance.
While the exact cause of the internal damage to the oil pump could not be definitively determined, investigators considered two hypotheses: premature failure due to improper handling or storage, or engine oil contamination by impurities.
Findings
- Pilot judgment: The pilot failed to use the aircraft checklist and did not set the propeller lever to maximum pitch, which could have reduced aerodynamic drag and improved glide performance. The pilot also made poor decisions regarding the emergency landing, specifically by retracting flaps and landing gear at a low altitude during the go-around, which is not recommended during an engine-out emergency.
- Maintenance: The aircraft's airframe, engine, and propeller logbooks were not up to date. Evidence of improper maintenance was found in the worn components of the propeller governor.
- Management oversight: The pilot's reliance on his local reputation led to an overconfidence that discouraged the use of checklists and regular flight training/proficiency updates.