Smith AEROSTAR601 N90339 accident near Heber, Utah

Probable cause

A recent hard landing resulted in a fracture of a joint from a cylinder to a main landing gear.

NTSB analysis

The pilot stated he touched down normally and during the landing roll, the airplane veered left coming to rest off the runway surface. The airplane sustained substantial damage to the right wing and horizontal stabilizer.

Postaccident examination of the landing gear assembly revealed that the weld had failed on the joint attached to the main landing gear cylinder and upper scissor assembly. Most of the fracture surface of the failure surface had been obliterated by smearing and grinding, consistent with post-fracture damage. The degree of the fracture surface damage was consistent with the fracture and separation happening before the accident. Landing gear components are under cyclic loads at every landing and during landing actions (such as braking or taxiing). There was no evidence of fatigue, corrosion, or other progressive mechanisms would have led to the fracture of this joint from the strut cylinder.

It is likely that a recent hard landing fractured the joint from the cylinder, but it could not be determined whether this occurred during the accident landing or beforehand due to the damage incurred after the gear collapsed.

Text from the NTSB. Open the NTSB docket for WPR18LA272 for the full record.