What happened
On September 3, 2001, at 21:17, a Cessna 172G, registration OB-1100, was conducting a flight in the Nazca circuit at an altitude of 3,200 feet. While maneuvering near the 'ballena' (whale) pattern, the pilot reported high engine temperatures and low oil pressure, followed by a loss of engine power.
The pilot notified the Nazca tower of the intent to return and requested a descent to 3,000 feet. During this descent, the aircraft began losing airspeed. The pilot declared an emergency landing near a local toll plaza; however, due to heavy traffic in that specific area, a landing there was not possible. The pilot subsequently located a dirt track in the pampas and performed a forced landing. There were no fatalities among the pilot or the three passengers, though the aircraft sustained significant damage to the engine, propeller, and main landing gear.
The investigation
The investigation focused on the maintenance history of the aircraft. Records indicated that a 100-hour inspection had been performed on August 30, 2001, which included an oil and oil filter change. Investigators examined the components used during this service and the installation process.
Findings
- The oil filter installed during the recent 100-hour inspection was the incorrect model for the aircraft's Teledyne Continental IO-360-H engine.
- The replacement filter was not properly secured or tightened during installation.
- Engine vibrations caused the incorrectly sized and improperly installed filter to loosen, leading to a rapid loss of engine oil, which resulted in the loss of engine power.