Accident Details
According to a 45-hour student pilot, during a crosswind landing in a single-engine airplane, the right main landing gear tire touched down first, followed by the left main landing gear tire. Upon left tire contact, the pilot reported that "something went wrong." Suspecting a flat tire, the pilot held the left wing up to minimize weight on the tire. The airplane subsequently departed the side of the runway as the pilot was unable to maintain directional control.
Examination Findings
Post-accident examination revealed that the left main landing gear spring had fractured into two sections at the point where the foot-step attached to the spring. The fractured assembly, including the foot-step and bracket, was sent to a metallurgical laboratory. According to the Factual Report, the spring gear fractured where the foot-step was installed. The step had been welded to the spring gear by two transverse weld beads on the top and side, and two longitudinal weld beads on the lower surface. The report stated that the weld beads were tall and rounded with weld spatter on surrounding surfaces, inconsistent with good quality workmanship. The fracture intersected the longitudinal weld on the lower surface, and magnified examination revealed that the fracture initiated at this weld bead.
Maintenance History
The airplane's last annual inspection was completed in January 2007. Review of maintenance logbooks disclosed no entries regarding a weld repair on the spring gear. The owner, who had recently purchased the airplane, stated that no maintenance had been performed since the purchase. According to the manufacturer's Service Manual, the foot-step should be bonded to the steel landing gear spring with EA9303 or a similar adhesive. Additionally, FAA Advisory Circular AC43.13-1B CHG 1, section 4-89, titled "Aircraft Parts Not To Be Welded," part (A), states: "Do not weld alloy steel parts such as aircraft bolts, turnbuckle ends, etc., which have been heat treated to improve their mechanical properties."