ERA23LA041

The pilot reported that shortly after takeoff, the control stick started shaking violently fore and aft. A witness video confirmed that upon liftoff the airplane’s elevator and elevator trim surfaces began to oscillate. The pilot stated that he continued the takeoff because insufficient runway remained on which to abort, and that he had full control authority, but flew the traffic pattern 10 mph slower than normal due to the feedback on the flight controls. The video showed that the airplane flew the downwind leg at a constant altitude but appeared low based on its position relative to trees and structures in the foreground. The sound of the engine was smooth and continuous through the takeoff roll, the initial climb, and the crosswind and downwind legs of the left traffic pattern. At a point consistent with the base leg of the traffic pattern, the airplane decelerated and entered a left turn. The airplane banked steeply, the nose pitched downward, and the angle of descent steepened. The airplane’s descent appeared to shallow before it disappeared behind trees and the sounds of impact were heard. The pilot’s son, who was a passenger in the airplane, said, “He tried to turn it back, but our airspeed was so low [the plane] just started falling.” Flight control continuity was confirmed from the cockpit to the flight control surfaces. The elevator trim tab cable was intact, but free from its attachment hardware on the trim tab cable mount. Examination of the cable and its associated hardware revealed that the cable was not properly secured and pulled free of its mount. Because the maintenance records for the airplane were burned in the post-crash fire, the history of the assembly could not be determined after the airplane’s airworthiness date. It is likely that the pilot’s decision to fly at a lower airspeed and his distraction due to the fluttering elevator trim tab led to his exceedance of the airplane’s critical angle of attack during the downwind-to-base-leg turn, which resulted in an aerodynamic stall and a subsequent loss of control.

On October 23, 2022, at 1412 eastern daylight time, an experimental, amateur-built Stolp SDTR Too SA300, N160JR, was destroyed when it was involved in an accident near Lordstown, Ohio. The private pilot and passenger were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. In an interview with law enforcement after the accident, the pilot, who was also the owner and builder of the two-place biplane, explained he had just departed his home airstrip with his son in the front seat; the airplane was about 50 ft into the initial climb when he felt, and then saw, “the elevator shaking on the tail.” The pilot stated that he attempted to return to the runway, but “lost all control and [the plane] went down.” A witness located across the street from the airstrip said that the airplane departed to the south and circled around, heading north when he heard the engine “start to cut out.” The witness saw the airplane then bank left and nose-dive into the pasture. When interviewed, the pilot’s son stated that at takeoff “something seemed off” and his father announced there was something wrong with the elevator. He said, “He tried to turn it back, but our airspeed was so low [the plane] just started falling.” Another witness was standing on the pilot’s property and made a video recording of the flight. The airplane appeared to use nearly the full length of the grass strip and climbed at a shallow angle. At liftoff, the airplane’s elevator and elevator trim surfaces fluttered. The airplane flew the downwind leg at a constant altitude but appeared low based on its position relative to trees and structures in the foreground. The sound of the engine was smooth and continuous through the takeoff roll, the initial climb, and the crosswind and downwind legs of the left traffic pattern. At a point consistent with the base leg of the traffic pattern, the airplane decelerated and entered a left turn. The airplane banked steeply, the nose pitched downward, and the angle of descent steepened. The airplane’s descent appeared to shallow before it disappeared behind trees and the sounds of impact were heard. The pilot reported to a Federal Aviation Administration (FAA) aviation safety inspector that, at liftoff, the control stick began “shaking violently” fore and aft. He continued the takeoff and climb due to inadequate runway remaining to abort the takeoff. The pilot reported that he had elevator authority, but limited his movements of the control stick and flew the traffic pattern “10 mph slower than normal.” The pilot held a private pilot certificate with a rating for airplane single-engine land. The pilot completed the requirements for operation under BasicMed on March 23, 2022. He reported 1,100 total hours of flight experience on that date. According to FAA records, the airplane was manufactured by the pilot/owner in 1996. The airplane’s records were destroyed in the postcrash fire, so its maintenance historycould not be reviewed. The wreckage was examined and photographed at the accident site by FAA aviation safety inspectors. The tube-and-fabric airplane was consumed by postcrash fire. The tail section appeared structurally intact but was thermally damaged. The horizontal stabilizer, elevator, and rudder retained their fabric covering. Flight control continuity was confirmed from the cockpit to the flight control surfaces. The elevator trim tab cable was intact but free from its attachment hardware on the trim tab cable mount. Score marks on the underside of the elevator trim tab were of the same dimension and aligned with the disconnected cable end. The trim tab cable, its mount, and attachment hardware were retained for further examination at the National Transportation Safety Board Materials Laboratory in Washington, DC. Examination of the hardware revealed that the attachment bolt displayed a through-hole in the shank for the control cable, and a hat-shaped spacer beneath the nut. When tightened, the nut provided a clamping force to the cable in the through-hole between the spacer and the head of the bolt. Sliding contact marks were observed on the cable and the spacer beneath the nut on the attachment bolt. Hardware and cable dimension, torque, and thread-engagement measurements of the hardware revealed the nut reached the limit, or was bottomed-out, on the bolt grip. The nut reached the limit of its travel before adequate clamping force could be applied on the cable, which was consistent with cable movement and the sliding contact marks.