What happened
On August 31, 2004, at approximately 18:30 UTC, a Jabiru SK ultralight aircraft, registration CS-UKC, departed from the North parking area of João Paulo II Airport in Ponta Delgada for a recreational flight around São Miguel Island. The flight was intended to capture aerial footage of the Santana and Mosteiros areas.
Shortly after takeoff, while the aircraft was at an altitude of approximately 600 feet AGL over the final quarter of the runway, the engine suffered a sudden failure. The pilot immediately lowered the nose and initiated a right-hand turn with a high rate of descent. The aircraft crossed the airport perimeter fence and a roadside, eventually impacting a parking lot located outside the airport's northern boundary. The aircraft struck several parked vehicles, including a Renault 4L, an Iveco van, and a Peugeot 206, before the fuselage came to rest against a Ford Fiesta. The impact caused the destruction of the Jabiru SK and substantial damage to five parked cars. The pilot sustained minor facial abrasions, while the passenger suffered serious injuries, specifically fractures to both feet.
The investigation
The GPIAAF investigation examined the aircraft, the engine, and the pilot's documentation. Investigators found that the engine, while designed for aviation-style use, was being operated using 95-octane unleaded automotive gasoline instead of the standard 100LL aviation gasoline. Although the owner claimed a modification had been made to allow for this fuel type, no record of such a modification existed in the engine logbook or official certification.
Furthermore, the investigation revealed a significant lack of maintenance documentation. There were no records of inspections or maintenance performed on the airframe or the engine. The engine itself showed signs of poor combustion and internal leaks. Additionally, the pilot's flight logs were not up to date, and the pilot was operating under a Spanish license without having sought the necessary validation from the Portuguese authorities (INAC) for operations in national territory.
Findings
- The primary cause of the engine failure could not be definitively determined, but the engine showed evidence of inadequate maintenance and improper combustion.
- The use of 95-octane automotive gasoline instead of aviation-grade fuel was a significant contributing factor.
- There was a complete absence of maintenance and inspection records for both the airframe and the engine.
- The pilot was operating with a foreign license that had not been officially validated for use in Portugal.
- The aircraft's takeoff weight was approximately 425 kg, which exceeded the 360 kg maximum takeoff weight specified in its certificate of flight, although it remained within the manufacturer's maximum limit.