AD FAA-2020-0208

The FAA is superseding Airworthiness Directive (AD) 2015-13- 06, which applied to certain The Boeing Company Model 747-400 and 747- 400F series airplanes. AD 2015-13-06 required repetitive inspections of the longeron extension fittings for cracking; repetitive high frequency eddy current (HFEC) inspections of any modified, repaired, or replaced longeron extension fitting for cracking; and applicable on-condition actions. This AD retains the requirements of AD 2015-13-06. This AD also requires, for certain additional airplanes, repetitive inspections of the longeron extension fittings for cracking and repair if necessary. This AD was prompted by the FAA's determination that additional airplanes are affected by the identified unsafe condition. The FAA is issuing this AD to address the unsafe condition on these products.