Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2016-09-01, which applies to certain The Boeing Company Model 777-200 and -300 series airplanes. AD 2016-09-01 requires repetitive inspections for cracking of the left-and right-side forward outer chords of the pivot bulkhead, and related investigative and corrective actions if necessary. AD 2016-09-01 also provides a modification of the pivot bulkhead, which terminates the repetitive inspections. Since the FAA issued AD 2016-09-01, it has received reports that cracking of the left- and right-side forward outer chords of the pivot bulkhead were found at earlier compliance times than those specified in AD 2016-09-01 and determined that the inspection areas must be expanded, and that additional inspections are needed in areas that were modified as specified in AD 2016-09-01. This proposed AD would retain certain requirements of AD 2016-09-01. This proposed AD would require doing repetitive detailed and high frequency eddy current (HFEC) inspections of the longeron fitting and, for certain airplanes, the bulkhead assembly structure, for any cracking and doing all applicable on- condition actions. The FAA is proposing this AD to address the unsafe condition on these products.