First published September 4th, 2018
I would strongly suggest that they do. The question is: How do we provide them a smooth pathway to achieving appropriate certification, which would provide confidence to aero Level 3s.
With demand for aero NDT technicians rising appreciably - especially with composite material testing experience - I would suggest that this need could be met by the skills and experience inherent in the Oil and Gas, Power Generation, Pressure Vessel sectors, etc.
However, technicians are put off by the certification pathways currently available and the need to demonstrate sector experience (our ubiquitous ‘chicken-and-egg' situation). I would like to see a shorter route to aero certification made available for existing ASNT/PCN L1 and L2 holders from other sectors.
For this discussion, I will concentrate on aero carbon fibre (CF) composite material testing and the major methods involved; that is, UT and RT.
Of course, effective testing of composite monolithic skins and assemblies (including bonds to inserts) requires knowledge of manufacturing processes and, therefore, possible faults that could present themselves and how this would be indicated – like other industrial sectors.
UT of composites uses a compressional wave technique whose indications are relatively easy to interpret – bonds to inserts are of a somewhat different order. Shearwave techniques, as required for welds, etc, are not used. I would submit that shearwave techniques are more difficult to apply and indications harder to interpret. Application of RT and interpretation cannot be considered more difficult. For interpretation of results from both methods we come back to the materials science knowledge indicated above.
So, I would propose that we utilise the UT and RT skills already inherent in the whole of the NDT community and a short bridging course be developed to provide understanding of CF material science, utilising both theory and practical elements. To be included would be training in aerospace terminology. Of course, National Aerospace Boards and Certifying Bodies would have to be involved in the development and ratification of said courseware.
If such short courses already exist, then I would be pleased to be made aware of them. I welcome your thoughts on the above.