Airworthiness Directives; Boeing Model 747-100B, 747-200B, 747-200F, 747-300, 747-400, 747-400F, and 747SP Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain 747-100B, 747-200B, 747-200F, 747-300, 747-400, 747-400F, and 747SP series airplanes. This AD requires doing inspections of the midpivot bolt and midpivot bolt access door of the spring beam of the inboard side of the outboard struts for discrepancies, installing a placard on the midpivot bolt access door, and applicable corrective actions if necessary. This AD results from reports indicating that the midpivot bolt and midpivot bolt access door of the spring beam of the inboard side of the outboard struts were installed in the incorrect position. We are issuing this AD to ensure that the subject midpivot bolts and midpivot bolt access doors are installed in the correct position. If not installed in the correct position, a midpivot bolt could be overloaded and crack or fracture, which could result in the loss of the spring load path and consequent separation of the associated outboard strut and engine from the airplane.