Airworthiness Directives; Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Airplanes

We are adopting a new airworthiness directive (AD) for certain Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model 382, 382B, 382E, 382F, and 382G airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the upper and lower rainbow fittings on the outer wing are subject to widespread fatigue damage (WFD). This AD requires repetitive inspections of the upper and lower rainbow fittings on the outer wing to detect cracks propagating from fasteners attaching the fittings to skin panels, and related investigative and corrective actions if necessary; and replacement of the upper and lower rainbow fittings on the outer wing. We are issuing this AD to prevent fatigue cracking of the upper and lower rainbow fittings on the outer wing and skin-panel- to-fitting fastener holes, which could result in reduced structural integrity of the airplane and possible separation of the wing from the airplane.