Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 777-200 series airplanes. This proposal would require repetitive detailed visual and ultrasonic inspections of the lower flange of the flaperon inboard support to find cracking, and corrective actions, if necessary. This proposal also would require a modification, which would terminate the repetitive inspections. This action is necessary to prevent fracture of the inboard support structure, which could result in an in- flight loss of the inboard flaperon, structural damage, and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.