Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Airbus Model A310 series airplanes. This proposal would require inspecting the pressure-off brakes (POBs) installed on the power control units of the slats and flaps to determine their serial numbers; and replacing any POBs having affected serial numbers with new, serviceable, or modified POBs. This action is necessary to prevent failure of the retaining ring on the POBs, which could result in slat or flap blowback or runaway, with consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.