Incident Overview
During the takeoff roll, the airplane's nose wheel and nose gear housing separated and fell onto the runway. The pilot subsequently returned to the airport and executed an emergency gear-up landing on a foamed runway.
Post-Accident Examination
Examination of the outboard nose gear housing flange revealed a complete fracture extending approximately 300 degrees around the area where the nose gear yoke assembly attaches to the housing. Additionally, both the left and right tow-limit stop bolts for the nose gear were found bent.
Investigation Findings
Review of maintenance records found no documentation of previous damage or any known overstress event involving the nose gear assembly. Scanning electron microscope analysis of the fracture surfaces showed no evidence of fatigue. Laboratory testing that induced overstress on a similar component produced a fracture surface with morphology comparable to that observed on the failed flange.
Conclusion
The investigation did not identify a specific cause for the nose gear failure. The absence of fatigue and the similarity between the fracture and overstress test results suggest the failure likely resulted from a single overstress event, but no such event was recorded or reported.