Fracture Mechanics and Fail-Safe Design for Helicopter Rotor Structures

  • M. J. Rich
Part of the Sagamore Army Materials Research Conference Proceedings book series (SAMC)


Fracture mechancis analysis is the key for design of fail-safe structures. Controlled fracture offers a substantial improvement for the design goal of increased safety and reliability of helicopter rotor system components. However, to achieve an overall gain the system must be inspectable and the fail-safe and safe-life features must be integrated. Fracture mechanics analysis is currently being used for many of the metallic rotor components with crack propagation time being the most important factor. The new advanced composites offer a substantial improvement in crack time but the emphasis may well now be in static fracture strength. By proper consideration of trade-offs in fail-safe and safe-life aspects lighter weight and increased safety can be achieved.


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Copyright information

© Springer Science+Business Media New York 1979

Authors and Affiliations

  • M. J. Rich
    • 1
  1. 1.Sikorsky Aircraft DivisionUnited Technologies CorporationStratfordUSA

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