Quad City CHALLENGER N528J accident near Kent, Washington

Probable cause

The pilot’s inflight loss of airplane control. Contributing to the accident was the pilot’s decision to fly the airplane without receiving training in its operation and flight characteristics.

NTSB analysis

The pilot-rated passenger had just purchased the light sport airplane and hired the pilot to relocate airplane to his home airport. The passenger/owner reported that the pilot stated he had no experience in the airplane make and model, but that he ferried airplanes for a living and was confident with no hesitations. After conducting a preflight inspection, the pilot and passenger boarded the airplane and the passenger briefed the pilot on the use of the airplane’s flaperons. The passenger reported that the airplane “swerved right” about 20 ft above ground level after takeoff, and that the pilot continued the climb while adjusting the flaperons. The pilot reported that, shortly after takeoff, the airplane became “unresponsive” to left stick inputs and entered an uncontrolled turn to the right. The pilot was unable to recover, and the airplane descended and impacted the roof of a storage facility, resulting in substantial damage to the fuselage and both wings.

The forward control stick aileron cables separated at the left aileron turnbuckle and right aileron cable near the forward pulley. The forward control stick aileron cable sections, including turnbuckles and forward pulleys, were removed for further examination. The flaperons were near the full-down position. Postaccident examination of the engine revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.

The right aileron control cable and the turnbuckle barrel for the left aileron control cable both exhibited ductile overstress fractures from abnormal loading, likely associated with impact. Even if either of the fractures occurred before impact, the ailerons could have been controlled by cables attached to the aft control stick.

The left pulley and support brackets showed multiple contact marks and scratches consistent with cable contact outside the normal pulley groove contact area, but no similar contact marks were observed on the right pulley. If the abnormal cable marks on the left pulley were the result of slack in the system before the fracture, similar marks would also be expected on the right pulley. The absence of abnormal cable contact marks on the right pulley suggests the marks on the left pulley assembly likely occurred due to impact rather than due to preexisting slack in the system.

Information from the airplane manufacturer stated that pilots should not attempt to fly without a proper type checkout. Information on the use of the flaperon system indicated that, under certain flight conditions with the flaperons extended, control stick pressures would become “heavy,” and in some cases, “an increasingly steep dive will result.”

The pilot reported no experience in the accident airplane make and model. It is likely that the pilot’s lack of familiarity with the airplane’s flight characteristics resulted in his loss of airplane control during flight.

Text from the NTSB. Open the NTSB docket for WPR23LA086 for the full record.