Airworthiness Directives; McDonnell Douglas Model DC-10-10, -15, and -30 Series Airplanes and Model KC-10 (Military) Airplanes

摘要

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas DC-10- 10, -15, and -30 series airplanes and Model KC-10A (military) airplanes. This proposal would require inspections to detect cracks of the upper aft mating bolt hole of the wing pylon truss fittings, and various follow-on actions. This proposal is prompted by reports of cracks found in the upper aft mating bolt hole of the wing pylon truss fitting located near the engine forward mount on Model DC-10-30 series airplanes, which were caused by fatigue-related stress. The actions specified by the proposed AD are intended to prevent fatigue-related cracking, which could lead to failure of the fitting, separation of a portion of the engine forward mount truss from the pylon, and consequent separation of the engine from the airplane.