Motoring to loss of control

I was driving along the other day when I saw something that perplexed me. Don’t get me wrong, I am often perplexed when driving – not because I don’t have a sat nav and get lost, but because of other drivers’ behaviour. No, this time it was a physical thing. Maybe you can explain it to me? Why do I need social media when I can crowd source answers to my queries through this column? LED lights are really useful if you are behind the torch in your hand, have them on your head or are sitting in the car that is blinding everyone else. If that car is coming towards you it is not so good, but if that car is coming up behind you it is not as bad, although it can still imprint dots on your retinas. So, I was driving along the other day when a car with its LED headlights on came rushing up behind me. Now, at this time of year you only need a flock of birds to fly across the sky and everyone puts their headlights on. On this particular day it wasn’t even dusk, so the headlights didn’t cause me to squint, which meant I was able to observe, as the car passed by, that none of the tail lights were lit.

Why? Do we only need to see cars that are bearing down on us? Do we not need to see them from the rear? Surely, if it is dim enough for lights at the front then it is dim enough for lights at the back? In my ignorance of the reason for this, I just think that it is yet another one in a long line of bewildering features added to cars: automated lights that don’t light up in fog; wipers that wipe when you just want to first spray the windscreen; and engine warning lights that cause undue worry and create money for dealers. Do the designers not drive cars? The recent software issue with Volkswagen comes as no surprise.

It is difficult to ensure that software does exactly what it is meant to do. It is not always possible to predict all the possible scenarios with which the software may have to be able to cope. Hence the need for regular updating, as different bugs are identified, when the software is used in anger in real-life scenarios. Nowadays, as experience of the internet will tell you and as the Volkswagen escapade illustrated, it is not just a case of whether the software is capable of performing the intended job, but what else might it be doing that you may not be aware of or you might not want it to do?

One drum I keep banging is the fact that non-destructive testing is, in QA terms, a ‘special process’. The aerospace industry has fully embraced this fact. The nuclear industry has fully embraced it for safety-critical inspections and partially embraced it for other inspections. Other industries embrace it for certain critical inspections but generally it is ignored. A special process is one where it is not easily evident, once you have applied the process, that it has done the job correctly. Hence, before it is applied it is important to generate evidence that shows it will meet the necessary requirements. In the case of NDT, it is a matter of establishing that the procedure will detect the defects of concern and that the operator is competent in applying the procedure correctly. The procedure encompasses the capability of the physics of the technique and the performance of the equipment, including the software.

Up until now, it has been possible to get away with ignoring the special process aspect of NDT because, generally, the applied techniques have been long established and cumulative industry experience, incorporated into standards, has provided some control of inspection quality. However, the times are a-changing. In recent years, there have been advances in ultrasonic phased array and digital radiography technologies, which have improved the capabilities of defect detection. This means that inspections not only find the defects of concern, but may also find many defects or material features that are not of concern.

In addition, these techniques are enhanced by the application of signal and image processing software. In the past, one flaw detector was very much like any other flaw detector. Now, two pieces of similar kit, designed to do the same job, may be significantly different. The performance of specific equipment and software has never been so important.

I will keep banging my special process drum and it may be the desire to avoid having to explain many small indications, rather than the desire to have confidence in detecting defects of concern, which finally gets everyone marching.

Please note that the views expressed in this column are the author’s own personal ramblings for the purpose of encouraging discussion within the NDT Newspaper. They do not represent the views of Amec Foster Wheeler or the HSE who funded the PANI projects.

Letters can be mailed to The Editor, NDT News, Newton Building, St George’s Avenue, Northampton NN2 6JB. Fax: 01604 89 3861; Email: or email Bernard McGrath direct at

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