Summary
The FAA is revising an earlier NPRM for an airworthiness directive (AD) that applies to certain McDonnell Douglas transport category airplanes. The original NPRM would have superseded an existing AD that currently requires, among other things, revision of an existing program of structural inspections. The original NPRM proposed to require implementation of a program of structural inspections of baseline structure to detect and correct fatigue cracking in order to ensure the continued airworthiness of these airplanes as they approach the manufacturer's original fatigue design life goal. The original NPRM resulted from a significant number of these airplanes approaching or exceeding the design service goal on which the initial type certification approval was predicated. This new action revises the original NPRM by removing certain service information as acceptable methods of compliance. We are proposing this supplemental NPRM to detect and correct fatigue cracking that could compromise the structural integrity of these airplanes.