Overview
MAAXIMUS (More Affordable Aircraft through eXtended, Integrated and Mature nUmerical Sizing) aims at achieving the fast development and right-first time validation of a highly-optimised composite fuselage thanks to a coordinated effort between virtual structure development and composite technology.
Even though composite materials are used more and more in modern airframes, many significant improvements are still achievable. Firstly, the substitution of the assembly of many small composite parts by a single one-shot large part provides additional weight reduction. Secondly, the final assembly line process must be adapted to composite properties (lack of ductility, stiffness). Thirdly, if the appropriate level of confidence and cycle time was available,
Simulation-based design would provide a faster and less expensive path to find the optimal structures than the current development process, which relies on physical tests. Lastly, more conductive composites are necessary to avoid additional weight for system protection. The aim of MAAXIMUS (More Affordable Aircraft structure through eXtended, Integrated, & Mature nUmerical Sizing) is to demonstrate the fast development and right-first-time validation of a highly-optimised composite airframe. The MAAXIMUS objectives related to the highly-optimised composite airframe are: 50% reduction of the assembly time of large composite sections; 10% reduction of manufacturing & assembly recurring costs; 10% reduction of the structural weight. The MAAXIMUS objective related to a faster development is to reduce by 20% the current development timeframe of aircraft structures and by 10% the corresponding cost.
The projects high level objectives may be summarised as:
Highly-Optimised Composite Fuselage:
- Enable a high-production rate: 50% reduction of the assembly time of fuselage section
- Reduce the manufacturing and assembly recurring costs by 10% compared to the ALCAS equivalent reference
- Reducing weight by 10%, compared to best available solutions on similar fuselage sections (F7X, A320 and TANGO fuselage)
Faster Development:
- Reduce by 20% the current development timeframe of aircraft composite structures from preliminary design up to full-scale test
- Reduce by 10% the non-recurring cost of aircraft composite structures from preliminary design up to full-scale test (ALCAS reference)
Right-First-Time Structure:
- Reduce the airframe development costs by 5% compared with the equivalent development steps in an industrial context
Funding
Results
Faster and cheaper fuselage development
Composites have helped the aircraft industry significantly reduce weight, fuel consumption and emissions. Simulation-based design and an advanced experimental platform will enable full exploitation of materials and slash time-to-market and costs.
Reflecting the spirit and value of teamwork, a huge international consortium of 57 partners from 18 countries launched the EU-funded project 'More affordable aircraft structure through extended, integrated, and mature numerical sizing' (http://www.maaximus.eu/pages/project.php (MAAXIMUS)). The team set out to enable faster development and right-first-time structure of a highly optimised composite fuselage.
Among the areas for improvement are single one-shot assembly, adaptation of assembly line processes to composite properties, better confidence levels and shorter cycle times of simulations. The technologies are predicted to reduce development time and cost by 20 % and 10 %, respectively. They will slash assembly time in half and reduce production costs and weight by 10 %.
During the project's sixth of its eight years, researchers continued to improve multi-criteria optimisation techniques with advances to a simplified acoustic model, the composites data model and consideration of non-destructive investigation (NDI) data. The team also completed the cost model based on a parameterised generic fuselage. In parallel, the team finished up most of the design work on structural subcomponents for physical testing and the simulations of manufacturing processes. The manufacturing test coupons have already been used in comparison of experimental and calculated results, and all the NDI defects data at the coupon level are available.
Perhaps the largest component of the MAAXIMUS project deals with simulating composite material behaviours during damage initiation, propagation and final failure. Extensive and comprehensive work has focused on the development of models considering damage from the micro scale to the barrel scale, with proper coupling between scales and careful control of the error in the solution. Reducing uncertainty plays a critical role in reducing redundancy, which translates to reductions in weight, cost and time. A new test rig for large structural components will eliminate the need for a barrel test for certification.
MAAXIMUS is nearing the finish line with final months to be devoted to full-scale validation of simulation methods and test procedures. Successful completion will put powerful tools in the hands of aircraft manufacturers, supporting them in efforts to significantly reduce the time and cost of development and assembly of composite aircraft fuselages.