Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-80 series airplanes and Model MD-88 airplanes, that currently requires inspection(s) to detect fatigue cracking of the shock strut cylinder of the main landing gear (MLG), and replacement of any cracked shock strut cylinder with a serviceable part. That AD also provides for installation of brake line hydraulic restrictors on the MLG brake systems, which, if accomplished, terminates the repetitive inspections. This action would require that the subject inspection be accomplished repetitively following installation of brake line hydraulic restrictors. This proposal is prompted by an additional report of fatigue cracking and subsequent fracturing of the shock strut cylinder of the MLG. The actions specified by the proposed AD are intended to prevent collapse of the MLG due to fracturing of the shock strut cylinder.