Airworthiness Directives; Dassault Model Mystere-Falcon 50 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Dassault Model Mystere-Falcon 50 series airplanes, that requires repetitive tests of double-skin feeder tanks for fuel leaks, and corrective actions, if necessary. It also requires modification of seals in the feeder tanks, which terminates the repetitive leak tests. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign airworthiness authority. The actions specified by this AD are intended to prevent fuel leaks from the feeder tanks, which could result in fuel vapors in the cabin that could come into contact with ignition sources. The actions are intended to address the identified unsafe condition.