What happened
On April 7, 2013, a Cessna 152, registration HK-2248 G, was operating as the lead aircraft in a three-plane formation for a flight training mission. The flight, operated by Aeroandes S.A., was traveling from Cartagena toward Barrancabermeja. During the descent phase, approximately 9 nautical miles from the Yarigüies Aerodrome (SKEJ), the student pilot noticed abnormal engine vibrations. The instructor took control of the aircraft and notified the other aircraft in the formation and the control tower of an impending engine failure and an emergency landing in an unprepared field.
While attempting the emergency landing at Finca El Lebrón, approximately 6.5 nautical miles from the aerodrome, the aircraft struck a perimeter wire fence. The impact caused a dynamic rollover, leaving the aircraft in an inverted position. The student pilot was uninjured, while the instructor sustained a minor shoulder injury. Both crew members evacuated the aircraft on their own and were later evacuated by a Colombian Air Force helicopter.
The investigation
The GRIAA investigation focused on the engine, fuel system, and flight planning. Laboratory analysis of fuel samples showed no signs of contamination. A subsequent test of the Lycoming O-320-E2D engine on a test bench confirmed that all components, pressures, and power outputs were within standard operating parameters, ruling out mechanical failure as the cause.
Investigators found that the aircraft was operating with a weight and balance that exceeded the manufacturer's limits. This increased weight resulted in higher drag and required higher power settings to maintain formation speed, which in turn led to increased fuel consumption. Upon inspecting the aircraft after the incident, investigators found only approximately 2 liters of fuel remaining in the distribution lines and wings.
Findings
- Fuel exhaustion caused the engine to shut down during the flight.
- The aircraft was operating outside of approved weight and balance parameters, which significantly increased fuel consumption.
- Inadequate flight planning failed to account for the increased fuel burn rate caused by the heavy load and the requirements of leading a formation.
- The impact with a fence during the emergency landing caused the aircraft to flip onto its back.