Airworthiness Directives; McDonnell Douglas Model DC-8-53, DC-8-55, DC-8F-54, and DC-8F-55 Airplanes; and Model DC-8-60, DC-8-60F, DC-8-70, and DC-8-70F Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain McDonnell Douglas airplanes, identified above. This AD requires a one-time inspection to determine the configuration of the airplane. This AD also requires repetitive inspections for cracking of the tee or angle doubler, and corrective actions if necessary. This AD results from a report indicating that numerous operators have found cracks on the tee. We are issuing this AD to detect and correct stress corrosion cracking of the tee or angle doubler installed on the flat aft pressure bulkhead. Cracking in this area could continue to progress and damage the adjacent structure, which could result in loss of structural integrity of the airplane.