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Fatigue detection in structural elements (bleeding structures)

Published online by Cambridge University Press:  04 July 2016

E. P. Donald*
Affiliation:
British Aerospace Dynamics Group

Extract

Fatigue is a problem which all designers have to face. If they are starting on the design of an aeroplane, they will work out all the high loading cases first, make sure that the design will be good enough to meet them, then they will turn their thoughts to the survival of the proposed structure within the lower stress levels of everyday operations.

Some parts may see one cycle, some hundreds, many will see thousands, some millions and millions. All should function without cracking from fatigue.

If fatigue cracks do appear after some time, this indicates that while the design was reasonably close to optimum, it needs a little more material adding locally. The operator will probably groan at the cost and disruption the beefing-up operation will require, and the designer will be tempted to overdesign in the first place to avoid this situation.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1979 

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References

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