Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: Extension of airbrakes above 360 KIAS [knots indicated air speed]/0.79 Mi [Mach indicated] results in aerodynamic driven vibration of the airbrake which, if not limited per Revision 14 to the AFM [airplane flight manual], can lead to high cycle fatigue failure of the airbrake in board hinge. The unsafe condition is high cycle fatigue of the airbrake in-board hinge, which can result in loss of the airbrake, which in turn can lead to reduced controllability of the airplane. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.