What happened
On February 13, 2020, an Aero Boero 180-RVR, registration LV-MFN, was conducting an aerial advertising mission involving the towing of a promotional banner. The aircraft departed from the Mar del Plata Glider Club to perform the task. After successfully detaching the banner during the climb phase, the engine began to lose power.
As the pilot attempted to maneuver toward a landing strip, the engine continued to fail. Unable to maintain flight, the pilot executed an emergency landing in a nearby cornfield. Upon impact with the terrain, the aircraft braked abruptly and overturned. The pilot was able to evacuate the aircraft without any injuries.
The investigation
Investigators examined the engine, propeller, and fuel systems to determine the cause of the power loss. While the pilot reported performing pre-flight checks, the investigation revealed that the fuel valves for all three tanks were in the closed position. The left tank was found to be empty, while the right tanks contained less than 25 liters of fuel.
Laboratory analysis of fuel samples from the main filter and storage tank confirmed that the fuel was uncontaminated and suitable for use. A technical inspection by an authorized repair workshop determined that the engine was in normal working condition and had no mechanical failures. However, investigators noted that the fuel quantity indicator, which relies on transparent hoses, was heavily soiled, potentially hindering an accurate reading of the remaining fuel.
Findings
- The engine failure was caused by fuel exhaustion.
- During a right-hand turn, the remaining fuel could not reach the engine because the aircraft's gravity-fed system was unable to supply fuel under that specific flight maneuver.
- The pilot failed to properly verify the fuel levels during pre-flight procedures.
- The fuel quantity indicator was unreliable due to excessive dirt accumulation.
Safety action
- Operators must ensure all necessary measures are taken to verify that fuel quantities are sufficient for the intended mission.
- Maintenance must be performed to ensure all onboard equipment, including fuel indicators, provides accurate and reliable readings.