What happened
During taxi operations, the crew of Flight 519 began their taxi roll after receiving confirmation that the area beneath the aircraft was clear for engine start and movement. The captain noted that a slight bump was felt during the initial roll, which was consistent with a rough ramp area. A passenger on board reported that a significant amount of thrust appeared necessary to move the aircraft on the level ramp without a jet-way, and described feeling two sharp jolts during the process.
Following these jolts, the aircraft underwent an emergency nose gear up landing, resulting in substantial damage to the airframe upon contact with the runway. The passengers were evacuated from the aircraft using emergency slides. Ground personnel later discovered that wheel chocks had been left on the ramp near the aircraft's position.
The investigation
An examination of debris recovered from Springfield, specifically focusing on the spray deflector assembly and the left-hand support assembly, was conducted by the NTSB Materials Laboratory. Microscopic examination of four fractured pieces from the center portion of the deflector assembly revealed features consistent with overstress separation in a casting. The investigation found no evidence of any pre-existing cracks on the fracture surfaces.
Findings
- Ground personnel were unavailable to flag the aircraft out due to simultaneous boarding duties for other flights.
- Wheel chocks were left on the ramp in the path of the taxiing aircraft.
- The failure of the nose gear spray deflector assembly was caused by overstress, which can be triggered by taxiing over obstructions such as chocks, taxiway lights, or potholes.