Airworthiness Directives; McDonnell Douglas Model DC-9, DC-9-80, and C-9 Series Airplanes; Model MD-88 Airplanes; and Model MD-90 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9, DC-9-80, and C-9 series airplanes; Model MD-88 airplanes; and Model MD-90 airplanes, that currently requires a visual check to determine the part and serial numbers of the upper lock link assembly of the nose landing gear (NLG); repetitive inspections of certain upper lock link assemblies to detect fatigue cracking; and modification of the NLG. The existing AD also provides for terminating action for the repetitive inspections. This amendment requires, among other actions, expanding the applicability of the existing AD, revising compliance times; and adding new inspection requirements. This amendment is prompted by a report indicating that an NLG upper lock link fractured prior to landing and jammed against the NLG shock strut, restricting the NLG from fully extending. The actions specified by this AD are intended to prevent the upper lock link assembly from fracturing due to fatigue cracking, and the NLG consequently failing to extend fully; this condition could result in injury to passengers and flight crew, and damage to the airplane.