Accident Summary
On September 11, 2019, at approximately 1730 eastern daylight time, a Beech K35, registration N5300E, was involved in an accident at Northeast Florida Regional Airport (SGJ) in St. Augustine, Florida. The commercial pilot and a pilot-rated passenger sustained minor injuries, and the airplane was substantially damaged. The flight was conducted under 14 CFR Part 91 as a personal flight.
Sequence of Events
According to the pilot, about halfway through the landing rollout on runway 13, the airplane suddenly veered to the right while the engine power was at idle. She attempted to correct the turn by applying left rudder pedal and brake but was unsuccessful. She confirmed with the pilot-rated passenger that the power remained at idle. The airplane departed the runway onto the grass, struck a berm, flipped over, and came to rest inverted. The pilot stated that the veer occurred before she could apply the brakes or retract the flaps from the 10° position. The airplane was not equipped with optional copilot-side brake pedals.
Post-Accident Examination
A Federal Aviation Administration inspector examined the wreckage and the accident site. Substantial damage was found to the fuselage forward of the windscreen, both horizontal stabilizers, and the left ruddervator. A black skid mark was observed on the runway leading from the right edge to the grass. Both wheel brakes, ruddervators, and nosewheel steering functioned normally when the rudder pedals were pressed. The parking brake was found disengaged. Visual inspection of the brake components revealed no mechanical or thermal damage to the brake discs, calipers, or pad material, and no hydraulic leaks were visible. Both main landing gear wheels rolled smoothly when the airplane was moved during recovery. The right main landing gear tire had a flat spot worn through the reinforcement cords in the tire tread.
Mechanical Findings
The airplane’s most recent brake maintenance was performed on January 24, 2019, the same day as the annual inspection (airframe total time then: 6,462 hours). During that maintenance, the right brake caliper was replaced. The airplane had flown about 60 hours since. A video clip provided by the pilot showed that the right brake caliper had some play between the two anchor bolts and the bushings in the torque plate; the caliper shifted about the bolts when moved by hand in a twisting motion. The right brake master cylinder was removed and disassembled: the o-rings were intact with no signs of leakage, the return spring was intact, the cylinder exhibited no scoring or abnormal wear, and the poppet valve operated normally. The parking brake actuator valve was examined by the NTSB’s Materials Laboratory. It operated normally when compressed air was applied to the inlet port. Upon disassembly, the o-ring was intact, and the spring-loaded ball, ball seat, and plunger were undamaged; the plunger moved freely when the actuator arm was moved back and forth.