Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2013-08-11, which applies to certain The Boeing Company Model 737-900 and -900ER series airplanes. AD 2013-08-11 requires repetitive inspections for cracking of the fuselage skin along chem-mill steps at certain crown skin and shear wrinkle areas and repair if necessary. Since the FAA issued AD 2013-08-11, the FAA has determined that the compliance times are not adequate. This proposed AD would continue to require the actions in AD 2013-08-11 but at reduced compliance times and would require post-modification inspections if an optional modification is accomplished. The FAA is proposing this AD to address the unsafe condition on these products.