No fault found: taking a look inside aircraft maintenance

Posted on 30 Oct 2012 by The Manufacturer

“Shallow men believe in luck and circumstance. Strong men believe in cause and effect.” – Ralph Waldo Emerson.

Human bodies and aircraft might not seem to be very similar at first glance, but they do share one common characteristic; when they go wrong, the consequences can be disastrous.

Humans are susceptible to myriad conditions, disorders and ailments that can be restrictive, debilitating or lethal; our first knowledge that something is wrong is a symptom, but often we must rely on the expertise and judgment of those operating within the medical profession to deduce from the symptom what the condition is and how best to treat it.

If they are correct, then the condition may be cured, managed or eased, allowing the person to continue living or operating as usual. But if the condition is incorrectly diagnosed, this can cause more harm than good, as adverse long term effects arise from incorrect treatments, prescriptions. Worse still, sometimes doctors conclude that symptoms are not indicative of anything and a patient can be incorrectly dismissed.

In the aerospace and defence sectors, this latter occurrence is commonly known as ‘No Fault Found’ (NFF). The circumstances surrounding its occurrence are broadly, if figuratively, similar. An aircraft component that is displaying some kind of fault in service is promptly removed or uninstalled and passed to maintenance or MRO engineers for testing, only for the test to return a conclusion of ‘No Fault Found.’ After this, the component is reinstalled into the aircraft where, of course, it repeats the faulty behaviour once it is back in service.

Alternatively, there may be nothing wrong with this component at all and it had been erroneously removed from the aircraft, leaving the original fault’s root cause still present on the aircraft.

A Rolls-Royce engine being tested - photo courtesy of Rolls-Royce
A Rolls-Royce engine being tested - photo courtesy of Rolls-Royce

The consequences of NFF are economically and operationally damaging; incorrect diagnoses, repairs and No Fault Found occurrences cost operators in terms of lost labour costs, maintenance costs, downtime and unavailability of aircraft. This can have further damaging effects upon reputation and relationships within the supply chain, and is a problem that is common throughout the global aerospace and defence communities.

Staff at Copernicus Technology Ltd, a UK SME based in Elgin, had previously developed a unique data solution to reducing the occurrences of NFF known as Symptom Diagnostics, which requires the handling, management and use of large amounts of ‘Symptom-Fault-Fix’ data.

Giles Huby, Managing Director of Copernicus Technology Ltd, says: “Symptom Diagnostics correlates the existing Symptom-Fault-Fix data to maximise the chance of a successful diagnosis, leading to an increase in first-time-fix-rate and subsequent reduction in NFF occurrences.” A similar system is already being used by the Ministry of Defence on the Tornado fleet, and BAE Systems is currently investigating this type of approach for both Typhoon and JSF.

Owing to a quirk of geographical convenience Copernicus Technology Ltd is based in an area that is burgeoning with technological developments in Life Sciences and Digital Healthcare. Cutting-edge new facilities abound, such as the Life Sciences centre currently being built on the Moray College campus of the University of the Highlands and Islands; and the Health Sciences incubation centre in Inverness. Their proximity meant that Copernicus Technology Ltd were able to converse with engineers working in the health technology sectors and identify that the same NFF problems occur when it comes to diagnosing human ailments.

Huby says: “the same thing happens with people as with aircraft. Patients with a symptom (like an aircraft fault symptom) visit a GP (repair technician), who then has to diagnose in order to identify and confirm the root cause before treating (repairing) the patient. And they don’t always get it right first time.”

Understanding how Symptom Diagnostic, and its underpinning means of handling big, complex data, might be applied to medical and life sciences could provide a profound shift in ways that illnesses and ailments are understood, identified and treated in the future.

Andrew Fowlie, General Manager of Primary Care, Digital Health and Innovation at NHS Grampian, is enthusiastic of the crossover potential: “the human body and the aeroplane may be different but the technologies we are working on are sometimes similar. Regenerative medicines, Artificial Intelligence, Augmented Reality, predictive models, remote monitoring, 3D- printing, and smart implants / medicines are all interchangeable between sectors.”

This occurrence of possible technology transfer from one sector to another is neither new nor unique, but the fact that it was enabled by geographical coincidence is indicative. Technology transfer should not simply be thought of as happy happenstance, but as a serious means of accelerating innovation, solving existing sector-specific problems, the de-duplication of effort, and identifying new markets and routes to markets.

Technology transfer can also help illuminate areas that we currently do not know are unlit, areas which former US Secretary of Defence Donald Rumsfeld might term the ‘unknown unknowns’; in other words, there may be applications for technologies and solutions for problems of which we are currently completely unaware.

All of this makes economic sense, but because of technology transfer’s tendency to occur accidentally or serendipitously, it might be assumed that strategies to enable it are not workable. Technology transfer cannot be forced or predicted, but creating the optimum conditions in which technology transfer can occur is in the interests of business.

It is something that the UK’s Knowledge Transfer Networks are well placed to enable. Between them, the KTNs’ memberships cover almost all areas of technology of interest to the UK, but relatively little is done to enable the cross-sector exchange of ideas and details of technologies being developed.

The interconnected web of Knowledge Transfer Networks is well placed to try and produce the optimum conditions for this type of serendipitous creativity to materialise. Inviting industrial representatives from the Health Tech sector to an event or workshop on aircraft Maintenance, Repair and Overhaul might seem slightly risky or even daft at first glance, but it is this managed-risk approach that might help uncover new areas on the map of our understanding.

We should be encouraging automotive engineers to occasionally attend financial or cyber security events; haptics specialists to listen to presentations from the Modern Built Environment sector, and all of the other myriad combinations out there.

In our instance of the challenges of No Fault Found having crossover applications in the health sector, the will to engage and make these ideas a reality is strong.  As Fowlie says, “our goal is to leverage progress from all angles into tone health system so that local citizens and clinicians can join up advances in an integrated and (almost) invisible manner. We get healthier citizens, better decisions and greater productivity.”

If this type of cross-pollination increases across sectors significantly, is feasible that we might begin to move away from a world by which technologies are traditionally stove-piped by sectors, and toward one where the concept of sectors is replaced by applications in the knowledge that any number of technologies need not be limited to their intended uses.  Cause and effect can be used retroactively to explain and subsequently predict any number of outcomes in the sphere of human experience. Yet, with a little daring we can begin to cause our own effects, effects that will change lives in ways that we cannot even know yet.

If you would like to find out more, further discuss the issues surrounding technology transfer, or suggest some potential areas of interest regarding aerospace, please get in touch.

Daniel Jones
Network & Communications Manager, Aerospace, Aviation & Defence KTN
Email: [email protected]
Twitter: @dgjones81 @AeroDefKTN