When flying in an airplane, you can typically guess when it’s about time to land: you can hear – and feel – the landing gear being lowered. This is because most medium range aircraft (think A320), use landing gear comprised of many moving parts, all of which are located directly under the aircraft’s wing. Not only is this set-up heavy and inefficient, it’s also prone to a number of mechanical problems. To overcome these limitations, researchers with the EU-funded ITEMB project redesigned the main landing gear bay using state-of-the-art composite materials. “ITEMB explored a different scenario, one based on an integrated landing system created with composite materials and located inside the aircraft’s fuselage,” explains project coordinator Sergio Cotecchia. The result is a landing gear system that helps make air transportation more sustainable. ITEMB also supports the EU’s Clean Sky objective of improving the environmental performance of aircraft by reducing harmful emissions and noise. From many to monolithic According to Cotecchia, the use of composite materials reduces the weight and cost of the landing gear’s structural component. However, using these materials first required engineers to move away from traditional design paradigms for metal components and to 'think in composite'. “What we created is a single composite structure of the carriage bay that reduces assembly costs by optimising and integrating the entire design, construction, and maintenance of the aircraft,” he explains. ITEMB’s main landing gear bay is comprised of just two components: the horizontal roof and the rear pressure bulkhead. “We have physically shown the possibility of producing such a complex structure as the main landing gear using only two large, one-piece components,” adds Pietro Cerreta, the project’s technical manager. “Our innovative ‘bag against bag’ engineering technique is very suitable to composite materials and has decreased the number of junctions and parts used by more than 95 %.” Decreasing weight, increasing efficiency ITEMB’s monolithic design makes assembling and repairing landing gear significantly easier. In fact, this increase in efficiency means that aircraft manufacturers can now assemble aircraft faster – up to 60 per month. Less parts also means less waste and lower production costs. For example, the use of composite materials equates to a 21 % decrease in the weight of the pressure bulkheads. This significantly lowers the weight of the landing structure and increases the aircraft’s overall efficiency. “ITEMB demonstrates that a one-piece design, without the need for special or expensive materials, is a cost-effective alternative for manufacturers,” says Cotecchia. “Taken together, these achievements have helped increase Europe’s competitiveness in the manufacturing of aeronautical structures.” The ITEMB process can be adapted for use with other aircraft components, thus achieving even more efficiencies. The project’s design principle is already being applied to developing the wing of a new UAV for civil applications. As researchers work to promote the project’s supply chain to the market and look for initial customers, they are also evaluating the possibility of patenting the ITEMB system.
ITEMB, aviation, Clean Sky, landing gear, composite materials, sustainability