Accident Overview
On January 5, 2025, at approximately 1700 eastern standard time, a Helio HT-295 airplane, registration N18JC, was substantially damaged during a landing accident near Marion, Ohio. The commercial pilot, who was the sole occupant, was not injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a positioning flight from Buffalo Niagara International Airport (BUF), New York, to Coleman A. Young Municipal Airport (DET), Michigan. The pilot diverted to Marion Municipal Airport (MNN) due to deteriorating weather conditions and executed a visual straight-in approach to runway 31.
After a normal landing, the pilot reported hearing a "pop" followed by a right-leaning tendency. Despite corrective flight control inputs, the airplane continued to turn right, departed the runway, and came to a stop upright in the grass. The pilot secured the airplane and was met by first responders.
Examination Findings
Federal Aviation Administration (FAA) inspectors examined the wreckage and found substantial damage to the left wing and left stabilator. The right main landing gear spring had separated at its fuselage connection point. The remaining portion of the spring inside the fuselage was removed, and the outboard section was secured. Both parts were sent to the National Transportation Safety Board (NTSB) Materials Laboratory for detailed examination.
The laboratory examination revealed that the spring fractured at the upper, inboard end, between the inboard attachment hole and the outboard support bracket, approximately 4.5 to 4.75 inches from the inboard end. The fracture surface exhibited chloride intergranular stress-corrosion cracking, which transitioned to fatigue cracking over time, finally resulting in ductile overstress failure.
The gear spring was identified as Cessna part number 0741001-8, reportedly used on the Helio HT-295. The spring showed signs of rework after manufacture, including chamfers with variable width and geometry. Grinding marks on the chamfer surface were oriented perpendicular (transverse) to the lengthwise direction of the spring. Additionally, there were areas of missing paint and corrosion pitting. According to Cessna Specification CSPS026, grinding of the main landing gear spring is permitted only in the longitudinal direction; transverse grinding is not allowed on edges or flats.
Maintenance History
The operator reported that no aircraft logbook entries indicated removal or reworking of the main landing gear since they purchased the airplane in September 1998.