AD FAA-2017-0779

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 787-8 airplanes. This AD was prompted by a report of possible degraded bond-line performance of co-bonded upper wing stringer-to-skin joints. This AD requires repetitive inspections of certain upper wing stringers for any disbond and corrective actions, if necessary; and a terminating preventive modification of installing disbond arrestment (DBA) fasteners. This AD also requires revising the inspection or maintenance program to incorporate an airworthiness limitation. We are issuing this AD to address the unsafe condition on these products.