February 10, 2017 – Federal Register Recent Federal Regulation Documents

We are superseding Airworthiness Directive (AD) 2013-19-04 for certain The Boeing Company Model 737-600, -700, -700C, -800, and -900 series airplanes. AD 2013-19-04 required repetitive inspections for cracking of the skin around the fasteners common to the ends of certain bulkhead chords, and related investigative actions and corrective actions if necessary; and provided an optional terminating modification. This new AD reduces the inspection threshold and repetitive inspection intervals. This AD was prompted by a report of cracks found in the skin at fasteners of certain bulkhead chords. We are issuing this AD to address the unsafe condition on these products.

We are adopting a new airworthiness directive (AD) for certain Airbus Model A300 series airplanes; and Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called Model A300-600 series airplanes). This AD was prompted by a determination that certain inspection thresholds and intervals must be reduced. This AD requires repetitive detailed inspections for corrosion of the lower wing root joint, and related investigative and corrective actions if necessary. We are issuing this AD to address the unsafe condition on these products.

We are adopting a new airworthiness directive (AD) for Alexander Schleicher GmbH & Co. Model ASK 21 gliders. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 cable slack in gliders equipped with a rudder hand control system leading to a short-term blockage of the rudder control system and reduced control. We are issuing this AD to require actions to address the unsafe condition on these products.