DAMAGE TOLERANCE ASSESSMENT OF THE HH-53 HELICOPTER

The success of the damage tolerance approach has provided the Air Force with an effective structural maintenance plan for its inventory of fixed wing aircraft and engines. As a follow-on, the Air Force (WR-ALC) contracted Sikorsky Aircraft to perform a damage tolerance assessment (DTA) of the HH-53 Helicopter. The objective was to determine if DTA could be applied to selected helicopter rotor and airframe structure to provide safe and economic force management. The DTA methodology used in this study was based on previous experiences of the Air Force with fixed wing aircraft and engines. The efforts and results of this damage tolerance investigation will be discussed in detail. Conclusions, lessons learned, and recommendations will be discussed in reference to the damage tolerant capabilities of the selected HH-53 helicopter structure. Recommendations for the DTA requirements of new designs will also be discussed.