What happened
On March 17, 2022, at approximately 21:53 UTC, a Cessna 150L, registration PT-OYF, was conducting a nighttime instructional flight near Bragança Paulista, São Paulo. The flight, operated by Classic Escola de Aviação Civil Ltda., involved an instructor and a student pilot traveling from Fazenda Vale Eldorado Aerodrome to Arthur Siqueira State-Aerodrome.
During the flight, the crew performed a touch-and-go landing at the destination. While executing a planned go-around, the aircraft experienced a loss of altitude, prompting the crew to perform an emergency landing in a plantation located in the overshoot area of runway 1s. The aircraft sustained substantial damage, including a broken nose landing gear and damage to the fuselage and both wings. The crew members were uninjured.
The investigation
CENIPA investigators examined the aircraft's maintenance records and found that while the airworthiness certificate was valid, the airframe, engine, and propeller logbooks were not up to date. Specifically, the aircraft had flown approximately 240 hours since its last recorded 100-hour inspection, meaning several required 50-hour and 100-hour inspections had not been documented as completed.
Technical analysis of the engine, fuel, and oil showed no mechanical failures or abnormalities. Investigators also reviewed the cockpit procedures and identified a discrepancy between the manufacturer's recommended checklist and the version used by the flight school. The school's checklist omitted a critical step regarding the carburetor heat lever.
Findings
- The primary contributing factor was a discrepancy in the flight school's checklist, which failed to include the requirement to close the carburetor heat prior to a go-around.
- It is hypothesized that the carburetor heat lever may have remained in the open position, leading to reduced intake air density and a subsequent limitation of available engine power.
- This power loss likely caused the crew to misperceive an engine failure, leading to the forced landing.
- The operator's manual lacked alignment with the manufacturer's specifications, creating a risk of improper aircraft operation.
- Maintenance records for the airframe and engine were not current, with several required inspections missing from the logs.