What happened
On 17 January 2003, a Fokker 50, registration PH-FZE, was performing a scheduled commercial flight to Melilla Airport with 5 crew members and 14 passengers on board. During the landing on runway 15, the aircraft experienced a series of critical malfunctions. The pilot in command reported that the propeller reverse thrust could not be engaged and that the aircraft was not braking normally.
As the crew applied the brakes, the aircraft began to deviate to the left of the runway axis. During the landing roll, the tire on wheel number 3 burst. The loss of control and braking effectiveness caused the aircraft to leave the paved surface of the runway approximately 110 meters before the end of the pavement. The aircraft subsequently traveled through a 15-meter-high embankment at the end of the runway, causing the wing-fuselage attachments to break. The accident resulted in 10 minor injuries and the destruction of the aircraft.
The investigation
The CIAIAC investigation, supported by the Dutch Safety Board, examined the aircraft's systems, maintenance records, and flight data. Investigators analyzed the flight data recorder (DFDR) and cockpit voice recorder (CVR) to reconstruct the approach and landing sequence. The investigation focused on the braking system, the propeller reverse mechanism, and the electrical wiring of the landing gear.
Technical examinations revealed that the approach to the runway was highly unstable, with the aircraft's airspeed significantly exceeding the reference speed at 50 feet. Furthermore, investigators discovered a cross-connection in the wheel speed transducer wire harness for wheels 3 and 4. They also identified that certain circuit breakers had tripped, which prevented the selection of propeller reverse thrust.
Findings
- The approach to runway 15 was unstable, characterized by excessive descent rates, glide path deviations, and a touchdown speed significantly higher than the 95 kt reference speed.
- The crew was unable to select propeller reverse thrust due to the probable tripping of the "FLIGHT IDLE SOLENOID 1 & 2" circuit breaker.
- A cross-connection in the wheel speed transducer wire harness for wheels 3 and 4 caused heavy braking to produce a flat spot on wheel 3, leading to its deflation and reducing the braking capability of wheel 4.
- The runway strip at Melilla Airport did not comply with ICAO Annex 14 recommendations regarding dimensions and safety margins.