Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 2000 series airplanes, that requires replacing the dual shuttle valve in the number 2 hydraulic system with a new, improved valve. This action is necessary to prevent failure of the dual shuttle valve in the number 2 hydraulic system, with reduced maximum elevator rate on the left side, which could result in pilot-induced pitch oscillation and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.