If it ever was just about turning wrenches, aircraft maintenance has matured well beyond that—relying on data, computers, smart analysis and tasking to keep aircraft safe, efficiently. That trend continues to pick up speed with the digital revolution affecting just about every aspect of MRO, from predicting faults to troubleshooting them, training workers and managing the massive amounts of information that supports maintenance.
But it is not just digits that are flashing across MRO managers’ display screens. New repair and manufacturing methods are becoming important, and they are better at solving time, cost and even design problems. And the autonomy evolution, with drones, robots and other gizmos, is changing shop floors.
New technologies will help in lots of little ways and in some big ones, too. Let’s start with the problem confronting all airlines: using data to improve both the design and the maintenance of major aircraft components, the most important of which are engines. As both an OEM and MRO, MTU
Aero Engines sees these two problems as closely connected.
Friedhelm Kappei, head of industrial engineering at MTU, says most technical advances in MRO will be driven by digitalization. MTU recently began integrating its MRO data, including engine monitoring and inspection data, into a group-wide platform that can be used by either the manufacturing or maintenance divisions. The company is also investing heavily in its own engine trend-monitoring system. While the system is 12 years old, MTU is now focusing on a new web-based interface and integrating continuous operational data from engines.
Trend monitoring helps schedule shop visits, plan logistics and manage fleets. For example, “purchasing life-limited parts can start months before actual removals,” Kappei notes. Web-based trend monitoring makes all data both readily available and easier to combine with other data.
In the longer term, the MTU executive predicts big data will transform maintenance with proactive, predictive analysis: “We are reaching a point where developments could be called prescriptive, in that data gathered from operations such as region, de-rate, engine performance and shop information helps us forecast remaining on-wing time and optimal removal points.” And sensor data from engines will also help estimate scrap rates, thus improving parts purchasing and sourcing.
Global MRO providers are already doing some predictive maintenance. AFI-KLM E&M Innovations Director James Kornberg and Digital Vice President Rodolphe Parisot cite their Prognos software as an important tool for removing components before they fail.
Kornberg stresses that Prognos is already yielding solid results. It has improved safety by cutting minimum equipment list defects and pilot reports in half, and it has improved economics by more than halving delays and cancellations. Prognos also increases aircraft availability, relieves pressure on supply chains and improves check schedules and cabin maintenance. Finally, Prognos cuts rotable inventories by 8% and capital expenditures by 10%, Kornberg says.
Achieving all this requires not only software, smart engineers and smart coders, but substantial investment in IT infrastructure, including toolpads with intuitive apps for mechanics and new portals to give airline customers the right information.
The company’s MRO Lab is also pushing new technologies, with its Fablabs center developing parts and tools using additive manufacturing and its digital innovation centers codeveloping and experimenting with new systems with partner airlines and others.
Kornberg and Parisot predict that eventually artificial intelligence (AI) on drones and robots will be able to detect more defects automatically. Maintenance schedules will be further optimized by data from aircraft, engines and components.
AAR President of Digital Services Jim Gross says augmented-reality wearable devices and inspection drones will be introduced at his company within the next 3-4 months, and AAR will use a combination of custom and off-the-shelf software to introduce a paperless hangar scenario.
Recruiting and retention are crucial MRO challenges, so AAR is creating internal workflow processes to streamline and better analyze staff retention and other key indicators of its human resources performance. Gross expects these innovations to speed turnaround times, reduce quality escapes and help counter any labor shortages.
“The Internet of Things, blockchain and predictive analytics are just a few technologies that will play an even more important role,” Gross predicts.
Alexander Simon-Sichart, head of technology innovation and research at Lufthansa Technik (LHT), would agree. First, he ticks off the technology advances LHT will be looking at over the next two years. Non-destructive testing of surfaces will be partially automated to improve both diagnosis and damage prediction. Text recognition will enable paperless maintenance with repair manual data incorporated into both automated processes and troubleshooting. And AI will optimize scheduling, for example, by automatically sequencing job cards. Further, AI object-recognition software will identify parts, increasing automated processes.
Simon-Sichart also sees robots and “co-bots” automating monotonous MRO activities. He predicts augmented reality will aid mechanics in scanning surfaces, for example, by displaying already known dents and buckles, and enable remote maintenance by certified staff.
On the hardware side, the LHT manager says cold spraying will preserve the strength of engine coatings to reduce part scrapping, additive metal manufacturing will allow fabrication of parts more quickly for engines, and additive plastic manufacturing will produce cheaper, faster and lighter cabin parts.
Down the road, Simon-Sichart forecasts even bigger possibilities. He sees physical assets being replicated by digital twins, which are continually updated by data from the physical assets as well as knowledge of human experts and data from similar parts. He expects that more robotics will be used, and energy harvesting from solar, thermal, wind, kinetic energy or salinity gradients will become significant. Agent-based contracting via blockchain will automate digital billing transactions, such as paying for the ground power units that charge airplanes. And volumetric displays will represent assets in three dimensions, giving 360-deg. spherical viewing angles as viewers move around, Simon-Sichart says.
By and large, independent MRO experts agree with MRO managers on the major directions of change.
David Marcontell, who manages MRO consulting at Oliver Wyman, predicts further refinements of machine learning and AI will help extract value from many data sources, especially from dirty or unformatted data.
He predicts more efforts to install sensors on key components and systems of older aircraft to aid predictive maintenance. “This is still very nascent, but the business cases are improving, and modifications are beginning to happen, especially at large airlines,” says Marcontell. Connecting older aircraft will improve their reliability, but older aircraft reliability will still decline with age. “Essentially, sensors and data delay symptoms of age and decay,” he observes.
Eventually, the Oliver Wyman consultant believes the Internet of Things will facilitate inventory planning, tracking and repair management. Either transactions or components themselves will be connected to the internet, transmitting locations and environments. “A lot of people are beginning to think in these terms. Think about everything that is available about you from your smartphone,” he says. “If the component or maintenance activity is connected to something like a smartphone, it would open a whole new world of possibilities.”
Alton Aviation Consultancy Managing Director Jonathan Berger argues that maintenance in the next five years will experience more innovation than in the past two decades. He attributes this acceleration to airlines’ better financial position, need to conserve scarce labor and reliance on new mechanics already well accustomed to mobile devices and other digital tools.
“The MRO industry is going paperless and mobile,” Berger stresses. “Walking back and forth to obtain task cards, review maintenance manuals and get multiple signatures for aircraft records will soon be a thing of the past.”
Sensors and analytics will yield “step changes” in reliability as well as aircraft-on-ground frequency and duration, he says. And on the employee front, he sees virtual reality and wearable devices aiding both training and the transfer of knowledge from experienced mechanics to newer recruits.
Aviation consultant Richard Brown also sees change but worries about its implementation and how the benefits will be shared. Brown sees a rush to digital systems, as OEMs and MROs have launched many options that can improve dispatch reliability and reduce maintenance costs. Big data analytics could also reduce inventory levels, he notes.
But Brown thinks OEMs have focused mostly on reliability and less on MRO cost reductions. He argues that MRO providers have to start committing to real savings for operators and that OEMs must develop much better tools for forecasting part demand to avoid shortages, which have occurred recently during what were completely predictable shop visits. “If OEMs don’t have parts, operators will evaluate alternatives like [part manufacturer parts] or [designated engineering representative parts], even if they did not initially consider them.”
Predictive maintenance is about turning unpredictable events into scheduled ones. But even with better IT systems, mechanics need to trust results, and the results have to be trustworthy. “We don’t want even more unnecessary removals,” Brown explains. “That defeats the point.”
He notes that the latest generation of aircraft have been designed for smaller work packages, which should reduce hangar times. And he is seeing substantial investment in training tools such as using virtual reality, both in classrooms and on shop floors. Like Berger and others, he predicts a shift from paper to electronic records.