AD FAA-2018-0902

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 787 series airplanes. This AD was prompted by a report of an uncommanded descent and turn that occurred after an inflight switch to the spare flight management function (FMF). This AD requires an inspection of the flight management system (FMS) to determine if certain operational program software (OPS) is installed and installation of new FMS OPS and a software check if necessary. For certain airplanes, this AD also requires concurrent actions. We are issuing this AD to address the unsafe condition on these products.