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Purpose This paper aims to summarize the main features of the fuselage structure description within the Common Parametric Aircraft Configuration Schema (CPACS) data format. Design/methodology/approach The CPACS fuselage structure description includes the definition of arbitrary sheets and structural profiles which can be combined with a variety of material definitions to so-called structural elements. Besides the definition of these structural elements, the definitions of structural members, such as stringers, frames, floor structures and pressure bulkheads, as well as the definitions of the complex load introduction regions that transfer loads from the wings and the empennage into the fuselage shell are introduced. Finally, exemplary models generated with different mesh generation tools developed at the DLR Institute of Structures and Design are presented. These models are suitable for subsequent static or dynamic structural analyses. Findings The CPACS fuselage structure description is suitable for defining standard fuselage configurations including complex load introduction regions suitable for different types of structural analysis. Practical implications The work shows exemplary fuselage models generated from the introduced CPACS fuselage description suitable for subsequent static and dynamic structural analyses. As the CPACS standard is available for download, the described definitions may be used by universities, research organizations or the industry. Originality/value The work presents the definitions of the fuselage structure within the CPACS schema that were mainly developed by the authors employed at the DLR Institute of Structures and Design. The exemplary applications show models generated completely on the basis of the definitions described in this paper.

Composite energy-absorbing structures for use in aircraft are being studied within a European Commission research programme (CRASURV ± Design for Crash Survivability). One of the aims of the project is to evaluate the current capabilities of crashworthiness simulation codes for composites modelling. This paper focuses on the computational analysis using explicit ®nite element analysis, of a number of quasi-static and dynamic tests carried out within the programme. It describes the design of the structures, the analysis techniques used, and the results of the analyses in comparison to the experimental test results. It has been found that current multi-ply shell models are capable of modelling the main energy-absorbing processes at work in such structures. However some de®-ciencies exist, particularly in modelling fabric composites. Developments within the ®nite element code are taking place as a result of this work which will enable better representation of composite fabrics.

Over the last years a multidisciplinary aircraft predesign process chain was established at the DLR, including different numerical tools for the modelling and structural sizing of fuselage structures. To improve the flexibility and performance of this structural analysis part in the MDO process a new tool development has been started in 2016 called “Parametric Numerical Design and Optimization Routines for Aircraft” (PANDORA). The PANDORA framework is using the interpreted high-level programming language Python and is focused on using dedicated open-source packages. Within PANDORA a lot of new packages have been implemented, like a new interface to access CPACS data, a python based FE pre- and postprocessor, a FE data converter to build an interface between PANDORA and different FE solver and a visualization interface using “The Visualization Toolkit” (VTK). Some further packages to generate a FE model based on a CPACS file using the geometry core “Open Cascade” (OCC) and a new FE sizing algorithm is also under development. To simplify the usage of PANDORA and to keep it comprehensible - a graphical user interface (GUI) has been added using the PYQT toolkit. In this paper the current state of the PANDORA development is presented and initial applications are shown.