In the careful, conservative industry of aviation maintenance, repair and overhaul (MRO), gambles on the latest hot trend or adopting untested processes are not the norm. And yet, as with many industries, the recent pandemic has pushed even aviation MRO into new ways of working and thinking about the industry. Directly influenced by aviation manufacturers, there are new technology trends around Industry 4.0 that are improving productivity, safety and precision. With the arrival of 5G private wireless, has the time come to move to MRO 4.0?
Adoption in Practice
One organization that was catalyzed by the pandemic into making this shift was Lufthansa Technik. At the start of 2020, it had the modest goal of running a pilot on virtual engine parts inspection. The idea was to use a private 5G wireless network, provided by Nokia, at LHT’s Hamburg facility, to power their Virtual Table Inspection (VTI) application, which would allow their civil aviation customers to inspect their engines without having to travel to Hamburg. Then the pandemic hit in late February, early March, and what was to be only a trial, became the only way to do business.
The already available 5G network enabled them to provide an effective virtual inspection service with predictable performance and no downtimes. Instead of having to close, as so many businesses were forced to do in the opening months of the pandemic, Lufthansa Technik was able to continue the engine inspections by using the VTI trial. No wonder that, as a result of this, the 5G test case evolved quickly from trial to business-critical infrastructure.
With the various pressures on the aviation industry, from carbon reduction to the need for improved operational efficiency, remote inspection was, in retrospect, an obvious place to start. But 5G networking, with its very high bandwidth and low latency, as well as its support for massive IoT sensor networks and mobile applications, has the potential to enable many more use cases in the MRO 4.0 space.
5G Wireless Networks Exceed Expectations
It is probably worth pointing out that 5G isn’t the only candidate for wireless connectivity, but there are some very good reasons why it is getting all the attention.
There are a variety of alternate wireless technologies that support specific applications. As an example, there are LPWA (low-powered wide area) networks that come in a variety of flavors from Bluetooth LE to LoRa, which are used for communicating with IoT sensors and devices. Professional mobile radio such as TETRA is widely used for voice communications (push-to-talk), while Wi-Fi is almost universally used for moving data files, email and controlling very slow-moving vehicles. And then there are outliers, for instance, specialized machine-to-machine control protocols like wireless PROFIBUS.
Of all these competing technologies, only 5G can support all these use cases on one network. It does them more securely, has very high bandwidth, low latency and is extremely reliable. It offers superior coverage with greater spectrum flexibility and, of course, supports seamless handover between cells for mobile applications with no impact on latency or throughput – even at high speed.
From an industrial perspective, when contemplating the digital transformation of operations, the 5G story is far more compelling. One network to install, maintain and operate. One network to secure. It provides a connectivity platform for innovation without having to re-invest in a different communications technology for each use case. Looking at MRO 4.0 specifically, use cases can be identified that cover everything from the hangar to the parts warehouse.
Looking again at the Lufthansa Technik example of remote parts inspection, the company was able to display the finest details of individual parts, such as hairline cracks, using several ultra-high-definition (UHD) video streams in parallel. This could not have been achieved with Wi-Fi due to bandwidth limitations. The application also showed no drops, or increase in latency, when moving from one cell to another, which was another weakness with Wi-Fi. 5G cellular radio was designed to master the noisy radio environments typical in busy urban cores; so the many metallic surfaces found in the hangar, which typically cause interference for Wi-Fi, posed no problem for 5G.
Improving Inspections
Looking to new use cases, aircraft inspection can be supported by advanced technology operating on a 5G network. For example, connected drones using cameras and image analytics can be used to visualize difficult to reach areas, such as the top of the fuselage and tail. They can identify damage and anomalies that might need closer inspection such as dents, lightning strike damage, paint defects, fastener defects, corrosion and cracks.
Engine borescopy is often used to inspect difficult to reach parts without dismantling the component. 5G connectivity opens the opportunity for aircraft owners to remotely participate in the borescope inspection to allow for greater real time collaboration with the inspector and interactive digital documentation. This is already tested at Lufthansa Technik.
Enabling Augmented and Virtual Reality
5G supported augmented and virtual reality (AR/VR) is another promising technology for MRO. Use cases include inspections, customizations and repairs utilizing modified augmented reality systems currently used by aircraft manufacturers. Along with the VTI use case, Lufthansa Technik also trialed 5G for interior customizations using connected iPads. The AR system superimposed graphics generated by the CAD-based digital twin of the aircraft onto the interior, to let the engineer have access to the mandatory documentation to follow. Augmented reality will help to further support the engineer, bringing down the training efforts for specific modifications at the same time. The graphics can also help to identify the actual parts of the aircraft and show the steps for repair. Remote experts and clients can observe the repair using HD video and advise personnel while they are working.
Heads up displays and smart goggles can also be used for this case. The head gear must precisely track the movements of the wearer, which calls for extreme accuracy and low latencies, which only 5G can support.
Meanwhile, outside the hangar, repair personal can be trained on the aircraft that they are to service using virtual reality. A VR image of, for instance, an aircraft engine, can be projected using VR headsets and technicians can be led through the engine interacting with parts. In the most advanced form, they would be able to move parts out of position and into position, reaching around obstacles and learning the optimized set of movements for the greatest efficiency.
In the fullest implementations, trainees would wear sensors on their limbs, torso and head to synchronize their virtual body within the projected digital twin of the aircraft. All of these sensors have to communicate near-instantaneously to process the interactions and provide immediate feedback to the trainee. The 5G edge server can be employed to do this local processing and ensure <1ms latencies for precise movement control.
Addressing Issues Before the Start
During flight operations, sensors on the aircraft can record critical operational data to later be processed in the 5G edge cloud. Machine learning can be used to learn about the aircraft performance and historical rates of degradation of different components. These can help maintenance teams evolve from strict schedule-based maintenance to condition-based and, even, predictive maintenance.
While it is hard to imagine the MRO industry adopting a less rigorous maintenance schedule, analytics can identify out-of-schedule issues that may become critical before the next scheduled check. They may even be able to predict failures before even a well-trained technician will be able to detect an anomaly. 5G cannot only support these advanced sensor networks, but also quickly download the large log files from the aircraft while it is still on the apron.
Improving Efficiencies in the Hangar
There are also operational processes around the hangar and the warehouse that can benefit from 5G communications. Automated mobile robots (AMRs), which are the next generation of the older automated guided vehicles (AGVs), are a big trend in automated workspaces. The workflow management system can control the robots’ pick and delivery paths and optimize batches in real-time as demands for parts come in from mechanics and other MRO facilities. It can also warn robots of congestion and possible collisions.
AMRs on 5G have no practical speed limits. If they are operating in a warehouse where there are no people present, it is possible for them to move at much higher speeds than Wi-Fi controlled robots.
Other technologies available anywhere in the facility include location-tracking of smart assets, enabling better workflow management. Workers can also be directly connected to the wireless network, allowing not only push-to-talk and push-to-video communications, but health and safety monitoring of the worker’s condition, and the provision of productivity-enhancing devices and tools. For instance, warehouse workers can use hand scanners that read barcodes, optically scan items, respond to voice commands and present data on a tablet screen or smart glasses to speed the time required to manually store and retrieve parts.
The Journey to MRO 4.0
The digital transformation of MRO has been accelerated by the pandemic. Given the competitive cost pressures and sustainability challenges faced by the aviation industry, the digitalization trend can only be expected to accelerate. MRO companies need to think holistically about this evolution and design a long-term digital strategy to move to MRO 4.0. A critical component of this evolution will be installing mission-critical, wireless connectivity, that can support the high throughput, low latencies and sensor-communications required. All signs point to 5G as one of the key building blocks of the future MRO 4.0 platform.
