Action
Final rule.
Summary
We are superseding Airworthiness Directive (AD) 2006-22-15 for 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 2006-22-15 required repetitive inspections for cracking of certain panel webs and stiffeners of the nose wheel well (NWW), and corrective actions if necessary; and replacement of certain panels with new panels, which terminates the repetitive inspections. This new AD reduces a compliance time and adds certain inspections and an applicable repair. This AD was prompted by multiple reports of fatigue cracking in the NWW top panel and side panel webs and stiffeners. We are issuing this AD to prevent fatigue cracking of the NWW side and top panels, which could result in a NWW depressurization event severe enough to reduce the structural integrity of the fuselage.