Airworthiness Directives; McDonnell Douglas Model MD-90-30 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all McDonnell Douglas Model MD-90-30 airplanes, that requires revising the Airworthiness Limitations Section of the Instructions for Continued Airworthiness [MD-90-30 Airworthiness Limitations Instructions (ALI)]. The revision will incorporate certain compliance times for inspections to detect fatigue cracking of principal structural elements (PSE) and to add PSE's to the ALI. This amendment is prompted by analysis of data that identified reduced initial inspection thresholds, reduced repetitive inspection intervals for PSE's, and other PSE's to be added to the ALI. The actions specified by this AD are intended to ensure that fatigue cracking of various PSE's are detected and corrected; such fatigue cracking could adversely affect the structural integrity of these airplanes.