Why additive manufacturing could be addictive for MROs

This disruptive technology, also known as 3D printing, holds promise as – among other uses – a cost-effective way to reproduce legacy spares, reduce inventory, manufacture parts on the spot, and make tools and new designs in limited numbers.
While primes, including Rolls-Royce, Airbus, Boeing and BAE Systems, are using AM to manufacture parts for engines and airframes, others are finding interesting applications in cabin interiors, where modification and customisation contribute to brand differentiation.
In the Middle East, Etihad Airways Engineering (EYEng) began exploring the use of AM in 2015 and was the first MRO to gain European Aviation Safety Agency (EASA) approvals to design and certify AM cabin parts in the high-performance thermoplastic Ultem 9085.
The Abu Dhabi MRO collaborates in research and development with a number of organisations and is an active member of the committee defining AM standards for aviation.
Its technical and commercial partnerships with world-leaders in cabin interior parts, suppliers of large-scale AM printers and cutting-edge AM technology, complement its own research into new processes and new materials for aviation. The company also has partners in the UAE with strong investment and skills in 3D printing techniques.
“This supports our vision to have a significant percentage of cabin interior parts manufactured using AM printing techniques within 10 years,” said EYEng’s Bernhard Randerath, vice-president - design, engineering and innovation.
“Additive manufacturing enables us to enhance our cabin modification by quickly designing and producing customised parts,” he added. “The ability to make parts on demand reduces inventory and cuts cost, while allowing us to optimise parts for weight reduction and appearance. The ability to make custom tools and jigs is an additional benefit.
“We have no doubt that AM will make a huge impact for airlines and MROs,” said Randerath, adding that “some challenges” need to be addressed to achieve this, including the limited selection of material currently available.
In Germany, Lufthansa Technik (LHT) has set up an AM centre in Hamburg to expand the MRO’s competence and experience in the new technology.
Dr Aenne Koester, head of the centre, said it will serve as “a collaborative hub... to increase the degree of maturity of the technologies and to develop products that are suitable for production”.
A key focus of the LHT research is the development of AM repair processes. This poses “quite a challenge” as industry standards in the process of development and the goals of the parties involved – OEMs and MROs – “differ substantially”.
LHT and Swiss engineering group, Oerlikon, are midway through a one-year agreement to develop “robust and repeatable processes” for AM in MRO. The partners are using three AM printers in three locations to achieve a better understanding of the parameters influencing the performance of a part manufactured using this technology.
The goal of the triple test is to shrink the process tolerance and to establish methods and standards to achieve the desired performance goals with the required level of certainty. The two companies intend to share the results of their study with relevant industry bodies to help define standards for qualification and approval of aircraft components.
LHT says it has made significant progress in its work with nickel-based alloys used in highly stressed engine components. It is among the few companies currently able to perform a powder bed fusion hybrid batch repair – an AM process in which a damaged part, such as a blade, is repaired by replacing lost material.
• Etihad Airways Engineering is hosting the first airline/MRO additive manufacturing conference on March 6-7 at the Etihad Innovation Centre in Abu Dhabi. For information, visit aircraft-cabin-additive-manufacturing.redcabin.de