In 2024, progress was made on the implementation of two closely related projects from the first call for proposals of the Clean Aviation public-private partnership (within the Horizon Europe framework program). These projects are developing a liquid hydrogen tank concept for aviation.
Specifically, H2ELIOS made progress in developing a 150-kilogram-capacity demonstrator by reaching the preliminary design review (PDR) milestone. This was made possible through numerous analyses and empirical tests on a smaller scale, carried out by Aciturri (the consortium leader) and the other project partners.
In the NEWBORN project, the H2ELIOS tank concept is integrated into an electric power plant based on a fuel cell. Aciturri led the work package in the project and reached the PDR milestone for the conditioning and management systems for the hydrogen extracted from the tank.
Progress has also been made in defining the final tests for the demonstrators in both projects. Thanks to these projects, we have had the opportunity to participate in and contribute to various working groups with important entities, such as EASA and various aircraft and engine original equipment manufacturers (OEMs), aimed at facilitating the adoption of hydrogen as a fuel in aviation.
The FASTER H2 project, from the first call for proposals of the public-private initiative Clean Aviation, aims to develop a highly integrated aircraft fuselage demonstrator using thermoplastic materials. These materials are recognized as sustainable due to their reusability and the advanced manufacturing technologies used to process them, including in-situ consolidation.
Additionally, infusion processes will be developed and validated to ensure the robustness of the industrial process and allow for application at high production rates. These processes will be based on bio-based resins and focus on sandwich panel configurations, integrated double-curved skins using LRI technology, and fasteners using RTM technology.
In 2024, Aciturri worked on designing the tooling necessary to manufacture stiffeners with different profiles. These stiffeners will be integrated into the final demonstrator through the in-situ consolidation (IsC) process. They analyzed manufacturing capabilities and reviewed the stamping process and general process parameters.
Additionally, in line with improving the sustainability of our components, the first manufacturing tests have been carried out with a newly developed "Bio" resin for the LRI and RTM infusion processes.
Aciturri's participation in this project will promote progress in developing thermoplastic materials as a greener technology due to their recyclability and applicability to aerostructures. Additionally, a deeper understanding of infusion processes (LRI & RTM) will be achieved, particularly when using bio-resins instead of other commercial resins. This will promote the use of environmentally friendly materials in our products.
CRETAN
Funded by ESA through the GSTP initiative, the CRETAN project continues to evolve. The goal is to develop an integrated liquid oxygen and kerosene tank suitable for powering the second stage of a medium-sized space launcher.
Compared to the current state of the art, it is a highly innovative element, which makes it extremely complex to manufacture.
In 2024, several prototypes were successfully built to verify that the designed concepts could be manufactured within acceptable cost parameters and with the usual quality of Aciturri products. Additionally, component tests have been conducted to replicate the design's various characteristics. This data can be used to optimize the final weight of the tank and verify the structural behavior of the manufactured elements by providing feedback on the designs and calculations.
The project's success could soon lead to supplying the structure for the second stage of small launchers, with their integrated fuel and oxidizer tanks, to various space sector players.
TIANA
The TIANA project is a continuation of AERCOST and is also part of the Aeronautical Technology Program promoted by CDTI. It aims to study advanced manufacturing technologies and materials with high added value. TIANA will increase manufacturing rates to unprecedented levels and reduce the unit manufacturing cost of aerostructures by optimizing the industrial manufacturing and assembly line.
In 2024, Aciturri worked on several initiatives, conducting the first manufacturability tests for high-load frames using a new developing material, as well as repeating manufacturability tests to determine the optimal configuration for frames with very high curvature. Progress has also been made in designing a modular concept for a ventral fairing and manufacturing a first demonstrator of sandwich structures with dry fiber and infusion technology for a high-curvature configuration.
Aciturri's participation in this project aims to develop the capabilities necessary to overcome the technological challenges associated with cost, production rate, and eco-efficiency that will arise in the aeronautical market.
R-LIGHTBIOCOM
The r-LightBioCom project aims to reduce the environmental impact of new, high-performance, lightweight composite materials during production, operation, and disposal due to their inherent recyclability properties.
The r-LightBioCom consortium is led by the AITEX research center within Cluster 4 of the Horizon Europe program. It is made up of industrial companies Aciturri and Acciona Construcción, the Ricerche FIAT applied research center, and the universities and research centers Universitat Politècnica de Catalunya, Hochschule Kaiserslautern, Coventry University, Leibniz-Institut für Verbundwerkstoffe GmbH, DLR, and CIDAUT. The consortium also includes the companies AEP Polymers, Feyecon, and FECSA.
As the end user of materials developed by other project partners, Aciturri will design and manufacture a demonstrator based on aeronautical requirements. The characterization process for these materials is lengthy. In 2024, Aciturri provided support for developing these materials and technologies. Design and manufacturing activities will be carried out in 2025.
OVERLEAF
The initial objective of OVERLEAF (Cluster 5 of the Horizon Europe framework program) is to develop a 95 kg liquid hydrogen tank based on a storage solution patented by Aciturri. In addition, work is being done on the potential use of new materials for the construction of this tank.
Aciturri, as project leader and responsible for the design, has completed the design and calculation phase in 2024, achieving sufficient design maturity to make manufacturing viable using innovative methods for liquid hydrogen storage, such as additive manufacturing. Design optimization has reduced supply lines, ensuring not only safety but also gravimetric efficiency.
This project aims to develop a thermoplastic spoiler solution by researching new thermoplastic manufacturing technologies in line with the 2030 Sustainable Development Strategy.
As part of the 2022 call for proposals for the Aeronautical Technology Program (PTA), Aciturri is leading the “Innovative Aerostructures for Emissions Reduction—AIRE” project, in which Airbus Defence & Space (ADS), AERYS (Aeronautics, Engineering, Renewable Energies, and Security), Titania Ensayos y Proyectos Industriales, M. Torres, and Principia Ingenieros are participating.
In 2024, work continued on activities related to components made with thermoset materials. A control surface elevator consisting of three subcomponents — an integrated box, a leading edge, and a compensating flap — was selected as the test component. Testing has been completed for all these components, and the results have been analyzed to propose improvements to current production processes for this type of element.
In parallel, activities are being carried out to address the challenges posed by thick sandwich structures and aggressive ramps. All manufacturing tests for this type of structure have been completed, and the results are under evaluation.
Finally, the two milestones set for 2024 in the design and manufacture of the highly integrated thermoplastic spoiler, PDR and CDR, have been successfully achieved. Designs for the manufacturing tools have been finalized, and production of the complete component has begun.
The LIDER project aims to design new aerostructures for current and future helicopters. The project places particular emphasis on energy efficiency, decarbonization, aerodynamic improvements, environmental impact, and the circular economy without compromising flight and operational capabilities. The project takes a comprehensive approach that includes designing new components, researching the use of new lightweight materials, and developing new manufacturing, assembly, and installation technologies that meet the new specifications.
This year, Aciturri has worked on several initiatives, including carrying out a critical design review (CDR) for the two main components (the wing and landing gear fairing) and conducting manufacturability tests on the leading edges. The first infusion tests with thermoplastic resins were carried out to improve recyclability, in collaboration with AIMPLAS (Plastics Technology Institute). Additionally, a manufacturing tool for the asymmetrical tail boom fairing has been designed and manufactured for an infusion process in collaboration with CIDAUT.
The CDTI subsidized this project, and the Ministry of Science and Innovation supported it through the Aeronautical Technology Program.
In 2024, work progressed on developing tanks for storing pressurized hydrogen gas. A solid team was built from different disciplines, and its members had extensive knowledge of aerostructures. This team contributed to the development of the product.
The team completed the design of the 2-meter-long, 350-bar pressure tank and began manufacturing the first units using specialized equipment and machinery.
ValorH2 is a project funded by the 2022 Science and Innovation Missions Program.
