As a somewhat nerdy by-product of working in an industry that looks at manufacturing the world differently, I too find myself often viewing the world through an additive lens. Perhaps the place I do this most is when traveling on an airplane where I tend to scour the cabin for places where additive manufacturing (AM) could be present someday soon.
The lifespan of an aircraft, typically between 20 and 30 years, makes maintenance, repair and overhaul (MRO) and retrofit, both big and necessary businesses. Think of every plane you’ve been on in the last few years that still featured a now-defunct charging socket from the 1980s – aircraft are not changing overnight to keep up-to-date with consumer expectations. However, Airbus’ Global Market Forecast projects that over the next 20 years the commercial aircraft upgrades services market will be worth 180 billion USD.
According to a variety of market reports, aerospace accounts for roughly 20% of the AM market. It offers numerous benefits to the sector; part consolidation, reduced inventory, on-demand manufacturing, light-weighting reduced costs and fuel consumption. For replacement parts where timescales are tight, and downtime must be kept to a minimum, speed of delivery can be a game-changer.
Can (or indeed, should) you 3D print an entire airplane? Berlin-based BigRep is looking to answer that question from an interior perspective in partnership with Etihad Airways Engineering, taking a close look at every single part you see in the cabin, to explore where AM could offer a better solution.
“Currently we are jointly working together with the innovation unit of Etihad Engineering to identify parts within the cabin – predominantly large format parts – that could be candidates for 3D printing,” Daniel Büning, Head of Global Strategy at BigRep explains. “It could be headrests, it could be side wall panels, it could be part of the seats or entertainment system. The core idea is to work with their lead designers and engineers to establish a novel digital workflow for AM cabin design.”
Etihad is leveraging BigRep’s large-format polymer FDM (fused deposition modelling) systems, which will soon be located at its Innovation Centre in Abu Dhabi, to reimagine non-flying parts for new aircraft and retrofit installations. As Etihad is the first airline MRO permitted by the EASA to certify, manufacture and fly 3D printed parts in-house, it already has a substantial advantage over a significant hurdle.
“Imagine you have an aircraft that is 30 years old and there is a need to refurbish or retrofit them every other 5 to 10 years. Every one of those parts has to be certified,” Büning adds. “This is a major problem if you are not able to do that by yourself or with a certified partner.”
Taking this a step further, BigRep is already embedding “digital smartness” into parts in combination with digitally tailored design methods. Hybrid manufacturing is also being explored, using off the shelf 6-axis industrial robots to print onto half-finished parts independent of its geometry or size as a “digital value add-on.” The first proof of concept is a full-scale print of an Airbus A320 sidewall on the BigRep ONE. The part was scanned to create a “digital twin” which is used to provide information to the robot about the part geometry and print conductive tracks, antennas and ornamental features.
“For me, as an innovation director, I was always sure that AM would take off if you have functional integration,” Büning commented. “With dual extrusion and the right materials such as conductive or capacitive, it is possible to dramatically decrease the manufacturing process by embedding structural and functional performance within a single process chain. In my opinion, this is the way to go, and that’s why BigRep is pushing hard on this.”
The project is part of NOWlab@BigRep, BigRep’s internal innovation department which looks at what’s to come in the industry in the next five to ten years. So, while you won’t see these parts flying in your commercial airplane cabin tomorrow, the potential for future applications in functional integration and reducing production costs and time could be tremendous.
Over in Dubai, Emirates Engineering, part of the biggest airline in the UAE, has been actively exploring 3D printing for cabin parts for around two years and recently teamed with 3D Systems. The company, which provides MRO services for a wide range of Airbus and Boeing models, used selective laser sintering (SLS) to produce video monitor shrouds for its aircraft cabins.
The first batch was printed in partnership with UUDS, a European aviation Engineering and Certification Office and Services Provider based in France, using 3D Systems’ new Duraform ProX FR1200 material, a flame-retardant nylon-12 thermoplastic. The 3D printed monitor shrouds were 9-13% lighter than components manufactured traditionally and could lead to significant reductions in fuel emissions and costs across an entire fleet. The parts have undergone a range of tests and are in the process of receiving EASA certification before they are installed on select Emirates aircraft.
Emirates has already used AM to develop EASA-certified aircraft cabin air vent grills that were installed for on-board trials late last year. Both components are currently being evaluated before they are rolled out across Emirates fleet.
Airbus, the second biggest aerospace manufacturer in the world, is no stranger to AM and has already produced thousands of parts such as brackets, clips, and holding devices using polymer processes. The latest is a spacer panel, located alongside the overhead storage compartments on commercial aircraft, produced in partnership with Materialise and set to be the first 3D printed parts placed in the cabins of Airbus’s A320 Family jetliners at Finnair. To the passenger, the part won’t look any different on the outside, but its weight has been optimised with a bionic design to achieve a 15% reduction compared to the original.
“Conventional manufacturing has trained MRO managers to think in terms of manufacturing at scale to ensure cost benefits. AM is a game-changer because it allows for cost-effective production of even single parts,” Edouard de Mahieu, Project Manager, Manufacturing at Materialise told TCT. “AM enables the production of what is necessary now, even if it’s a highly customised part. Ultimately, when your spare parts production is free from the economies of scale, the winner is performance.”
The spacer panels are produced using Materialise’s Certified Additive Manufacturing process and then painted to Airbus cabin requirements, all using flame-retardant Airbus-approved materials. The Belgian company’s Certified AM facility holds several critical certifications including ISO 9001 for manufacturing and EN9100 and EASA 21.G for the aerospace industry which has already seen the company produce flight-ready parts for the Airbus A350 XWB. Materialise describes the process as more than a 3D print but rather “an entire quality system.”
“Quality in AM can be affected at each stage of the value chain. That’s why we have defined quality management processes for each step of the manufacturing process, from data capture to build preparation, production to post-processing, and final quality control,” Mahieu continued. “In order to define and hone these processes, we work very closely with our clients to understand their quality requirements and integrate them seamlessly into our infrastructure and workflows.”
Time to spare
SIA Engineering Company (SIAEC) recently formed a joint venture with Stratasys to establish an AM service centre for the manufacture of parts for commercial airlines. The Singaporean firm provides MRO services to more than 80 airlines worldwide. Combining SIAEC’s MRO industry knowledge and Stratasys’ AM leadership, the partnership aims to identify opportunities for 3D printing in aviation whether that’s advanced tooling or end-use cabin parts.
“We’ll do some prototyping work but we’re more focussed on advanced tooling and production part opportunities which are less obvious and may take the customer, such as an MRO, a very long time to discover for themselves,” Daniel Thomsen, Stratasys secondee, Deputy General Manager – Joint Venture with SIA Engineering Company told TCT. “We are trying to work extremely closely with our customers and help them identify these advanced opportunities.”
Initially, they will look at interior cabin components and non-critical, non-loaded, singular parts which Thomsen believes will not only be a good starting point to get engineers thinking differently about AM but also for regulators to understand and become familiar with the utilization of the technology.
“For successful deployment of AM, an MRO really needs to look at the pains in their services. The two pains that come to mind are unnecessary repetitive costs and extremely time-consuming workshop activities,” Thomsen explained. “These tend to be two good starting points. AM is an option and with strong knowledge behind that option, in many cases, can deliver the most economical and successful solution.”
Whenever an aircraft is not flying, it is losing money, so driving down lead times for replacement components is crucial for airlines. By adopting AM into their spare part workflow, MROs could have the ability to keep stock quantities significantly lower and manufacture lesser volumes on demand with a catalog of parts that have been designed for AM. Unlike some of the more elaborate AM concepts we’ve seen for the aerospace industry, this doesn’t mean overhauling the entire look of an aircraft. In fact, Thomsen says in his view “you won’t see them flying.” Cosmetically, AM cabin parts will look the same, adhering to each airline’s aesthetic, but instead, they might be enhanced by internal features that can’t be seen, such as lattices, to reduce material and weight.
“AM can produce more complex geometries where the complexity may not be seen due to being in the back of the part but will provide possibly stronger, lighter and more reliable parts than what was currently installed on the aircraft,” Thomsen adds. “This is certainly not just reproducing an existing part, but designing a new part solution, exploiting the benefits of AM”.