Preliminary Report: Cessna 172N Emergency Landing at Rodelillo Aerodrome

Incident Overview and Location Details On April 13, 2024, at 14:30 local time (18:30 UTC), a Cessna 172N aircraft made an emergency landing at Rodelillo Aerodrome (SCRD) in the Valparaíso Region. The aircraft had departed from Viña del Mar Aerodrome (SCVM) for a recreational flight. During the flight, the pilot reported engine vibrations and a loss of power, prompting the declaration of an emergency and the decision to land at Rodelillo. ## Occupants and Aircraft Information The aircraft was occupied by one pilot and one passenger. The pilot, a 36-year-old Chilean national, held a private pilot license for single-engine land aircraft and had a total of 115.00 flight hours, including 0.5 hours on the day of the incident. The Cessna 172N, manufactured in 1979 with serial number 17272034, had accumulated 12,758.2 flight hours. Its last 50 and 100-hour inspection was completed on February 26, 2024, at 12,723.60 hours. ## Damage and Investigation Findings The pilot and passenger exited the aircraft unassisted and sustained no injuries. The aircraft sustained damage to the engine, specifically the separation of cylinder number 4 from the crankcase assembly, three cut studs, and one stud missing its corresponding nut. The rocker cover guides were also misaligned from the engine block. A visual inspection of the engine, conducted after it was transported to SCVM, revealed oil residue on components and incomplete combustion residue on the spark plugs of cylinder number 4. No evidence of fire was found. ## Meteorological and Operational Context On the day of the incident, weather conditions at Viña del Mar Aerodrome included air temperatures between 11.4°C and 18.5°C, relative humidity between 56% and 84%, and wind speeds ranging from calm to 22 km/h. At Rodelillo Aerodrome, temperatures ranged from 11.4°C to 16.8°C, with relative humidity between 64% and 92.8%, and wind speeds from 3 km/h to 16 km/h. No precipitation was recorded at either location. The investigation remains in progress, with a fracture analysis of the cylinder number 4 studs conducted by a specialized laboratory.