Cessna T210 N6330N accident near Hurricane, Utah

Probable cause

Maintenance personnel's improper installation of a throttle cable to the throttle body arm, which resulted in a throttle detachment during takeoff and subsequent loss of power. Contributing to the accident was the inadequate inspection of the throttle installation by the certified mechanic.

NTSB analysis

The pilot departed on a maintenance check flight with his mechanic to troubleshoot an oil temperature discrepancy. During takeoff, after the airplane lifted off the ground and transitioned into a climb, the engine began to lose power. The pilot was unable to maintain altitude, and the airplane descended to the ground.

Postaccident examination revealed that the turbo waste gate was likely not functioning at the time of the accident. In addition, photographs taken moments after the accident showed that the throttle cable had detached from the arm of the throttle body metering unit and the bolt holes in both the rod end and throttle arm were intact. Further, maintenance records showed that the mechanic’s assistant (who was not a certificated mechanic) had removed and re-installed the throttle cable during the airplane's most recent inspection 1.5 flight hours prior to the accident. The assistant performed the removal by memory, and the reinstallation of the throttle assembly was likely not confirmed by the mechanic. The pilot was able to advance the throttle during takeoff, but the passenger observed mid-range fuel flow that was not consistent with takeoff power, which suggests that the throttle cable likely uncoupled from the throttle arm sometime during the takeoff sequence. As there were no anomalies with the airplane, the mechanic's improper installation of the throttle cable during recent inspection likely resulted in a detached throttle cable during takeoff, which resulted in a loss of engine power, subsequent descent, and impact with terrain.

Text from the NTSB. Open the NTSB docket for WPR19LA195 for the full record.