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Using the lead crack framework to reduce durability test duration

Published online by Cambridge University Press:  24 September 2019

L. Molent*
Affiliation:
Aerospace Division, Fishermans Bend, Australia
R. Singh
Affiliation:
Defence Aviation Safety Authority, Melbourne, Australia

Abstract

Aircraft full-scale fatigue tests are expensive and time-consuming to conduct but are a critical item on the certification path of any aircraft design or modification. This paper outlines a proposal that trades cycling hours for increased detail in the teardown of a metallic test article. A method for determining the equivalent demonstrated crack size (and crack growth curve) at the mandated test life utilising the lead crack framework is demonstrated. It is considered that the test duration can be significantly reduced, whilst still achieving all the desired outcomes of a certification program.

Type
Research Article
Copyright
© Crown Copyright. Published by Cambridge University Press 2019

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Footnotes

A version of this paper was first presented at the 18th Australian International Aerospace Congress in February 2019.

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