Introduction
On Monday, 20 October 2003, at 17:45 local time, a Cessna 172-RG aircraft, registration EC-HHX, experienced a nose gear failure during the landing roll at Badajoz Airport (Badajoz). The aircraft was engaged in a local instructional flight under dual control, with a student pilot and an instructor on board.
Event Details
The flight departed Badajoz Airport at approximately 16:45 for a one-hour local training flight. After completing normal training activities, the aircraft returned to the airport and conducted a landing. During the landing roll, the instructor noticed strong vibrations coming from the nose gear. He applied elevator control to raise the nose, which temporarily alleviated the vibrations. As the aircraft slowed, the effectiveness of the aerodynamic surfaces decreased, and the load on the nose gear increased. The vibrations reappeared and could not be attenuated. Shortly thereafter, the nose gear fork broke, causing the nose wheel to detach. The aircraft then slid on the remaining nose gear components and came to a stop a few meters further. The propeller struck the runway surface, causing damage. Both occupants were uninjured and evacuated the aircraft unassisted.
Investigation
Examination of the nose gear fork revealed it had a double-lug configuration that held the wheel axle. Both lugs were broken. The fracture surfaces were heavily worn due to friction during the slide after the break, preventing determination of the initial failure cause. The wheel, axle, and retaining components were undamaged, confirming that the wheel detached solely due to the fork breakage. The pilot stated that strong vibrations preceded the wheel detachment.
Conclusion
The report concluded that the vibrations reported by the crew were likely due to the breakage of one lug supporting the wheel axle, leaving the wheel supported only by the second lug. Subsequently, the second lug failed, possibly from static overload, leading to the wheel detachment. The cause of the initial lug break could not be determined because the recovered fracture surface was too worn for metallurgical analysis.