Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain British Aerospace BAe Model ATP airplanes and all Model HS 748 series airplanes. This proposal would require inspection of the main hydraulic accumulator for corrosion, and corrective actions, if necessary. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to detect and correct such corrosion, which could result in loss of certain hydraulic system functions, including nose wheel steering, hydraulic lowering of the landing gear, and main wheel brakes, which are essential for safe operation of the airplane.