Airworthiness Directives; McDonnell Douglas Model DC-9-80 Series Airplanes and Model MD-88 Airplanes

This amendment supersedes 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 amendment requires that the subject inspection be accomplished repetitively following installation of brake line hydraulic restrictors. This amendment is prompted by an additional report of fatigue cracking and subsequent fracturing of the shock strut cylinder of the MLG. The actions specified by this AD are intended to prevent collapse of the MLG due to fracturing of the shock strut cylinder.