Airworthiness Directives; Dassault Model Fan Jet Falcon Series Airplanes and Model Mystere-Falcon 20 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all Dassault Model Fan Jet Falcon series airplanes and Model Mystere-Falcon 20 series airplanes, that requires inspecting and testing for fatigue cracking due to stress corrosion in the vertical posts of the window frames in the flight compartment. This action is necessary to prevent fatigue cracking of the window frames, which could result in rapid depressurization of the fuselage and consequent reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.