Action
Final rule.
Summary
The FAA is superseding Airworthiness Directive (AD) 2017-18- 05, which applied to all The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. AD 2017-18-05 required repetitive replacement or inspection of certain fuse pins, and applicable on-condition actions. This AD was prompted by a report of damage found at the lower trailing edge panels of the left wing and a broken fuse pin of the landing gear beam end fitting. This AD was further prompted by the need for new inspections for cracking of the fuse pin, and the determination that additional airplanes are subject to the unsafe condition. This AD continues to require the actions in AD 2017-18-05 and also requires repetitive replacement of certain fuse pins, repetitive inspections for cracking of the fuse pin, and applicable on-condition actions. This AD also revises the applicability by adding airplanes. The FAA is issuing this AD to address the unsafe condition on these products.