Airworthiness Directives; The Boeing Company Airplanes

We propose to adopt a new airworthiness directive (AD) for certain 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. This proposed AD was prompted by an evaluation by the design approval holder (DAH) indicating that the nose wheel well is subject to widespread fatigue damage (WFD). This proposed AD would require modification of the nose wheel body structure; a detailed inspection of the nose wheel body structure for any cracking; a surface high frequency eddy current inspection (HFEC) or an open hole HFEC inspection of the vertical beam outer chord and web for any cracking; and all applicable related investigative actions including repetitive inspections, and other specified and corrective actions. We are proposing this AD to detect and correct fatigue cracking in the nose wheel well structure; such cracking could adversely affect the structural integrity of the airplane.