Airworthiness Directives; Learjet Inc. Model 45 Airplanes

We are adopting a new airworthiness directive (AD) for certain Model 45 airplanes. This AD requires a general visual inspection for cracked and missing ballscrew assembly sleeves of the flap actuator, repetitive non-destructive liquid penetrant inspections of each sleeve or flap actuator for cracks, and replacement or modification of the flap actuator if necessary. This AD results from reports of cracked and missing ballscrew assembly sleeves of the flap actuators. We are issuing this AD to detect and correct cracked and missing sleeves, which could cause loss of the load-carrying ball bearings on both actuators on one flap, resulting in flap asymmetry and loss of control of the airplane.