AD 2020-26-05 Requires An Inspection Of The Rivet Of The Left And Right Throttle Quadrant Assembly

The FAA is adopting a new airworthiness directive (AD) for certain Textron Aviation Inc. (type certificate  previously held by Cessna Aircraft Company) Model 560XL airplanes.

This AD was prompted by an incident where a Model 560XL airplane experienced an uncommanded engine acceleration with the left engine throttle unresponsive to power commands, including engine shut-off. This AD requires an inspection of the rivet of the left and right throttle quadrant assembly (TQA) sensor link and sensor drive arm pivot for correct installation and corrective actions if necessary. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective December 17, 2020.

Supplementary Information: The FAA has received a report of an incident where a Model 560XL airplane experienced an uncommanded engine acceleration on the ground following successful engine starts. The left engine throttle was unresponsive to power commands, including engine shut-off. An inspection identified that the left engine's sensor link and sensor drive arm (in the TQA) had separated. A sub-supplier of the TQA components failed to properly squeeze the rivet in a throttle quadrant link assembly. The rivet serves as the pivot between the TQA sensor link and sensor drive arm. The FAA determined that the failure of the TQA caused an asymmetrical uncommanded high-thrust that cannot be corrected by the flight crew in certain phases of flight.

This condition, if not addressed, could result in loss of thrust control, which could cause loss of control of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.

FMI: www.regulations.gov