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This special issue of the CEAS Aeronautical Journal summarizes articles describing results of the work package 'Load Control', which was part of the Smart Fixed Wing Aircraft (SFWA) project, taking place in the framework of the European Clean Sky research programme. The editorial first gives a short overview over the Clean Sky framework and the SFWA project. Second, the articles of the special issue are shortly introduced. more...

The article describes the use of the Multi-Body Dynamics (MBD) models, the Finite Element Analysis (FEA) and the CAD-modelling process in the automotive suspension development. Automation of maximum quasi-static loads calculation with the automatic two-way geometry update between MBD/CAD-models and automatic load transfer to the finite element analysis allows performing numerous analysis of suspension during development without significant time consumption, and, hence, provides an increased accuracy and reliability of stress analysis results. more...

Loads analysis and structural design are core steps of the aircraft design process. To reduce wing loads and with it the wing structural mass, methods of passive and active loads alleviation have been researched in recent years. However, those methods are currently implemented without the consideration of dynamic simulations or unsteady aerodynamics in the optimization process in aircraft predesign. The purpose of this research is to investigate the influence of passive and active loads alleviation methods on the structural mass in aircraft preliminary design. The methods have been applied on the wing of a Generic Mid-Range (GMR) aircraft configuration. The models have been created with ModGen, an in-house program at DLR Institute of Aeroelasticity. The models comprise FE-models for the structure and masses, as well as DLM (Doublet-Lattice-Method) model for the aerodynamics. For the investigation of the influence of the loads alleviation systems, a loop of loads analysis and subsequent structure optimization has been conducted. The loads analysis consists of gust and maneuver simulations. For the passive loads alleviation, an aeroelastic tailoring of the wing structure has been implemented, whereas for the active loads alleviation the ailerons are deflected to redistribute lift during maneuvers and to partially compensate lift increment during gust encounters. With the implemented methods, a first quantification of the influence of loads alleviation methods on the structural mass in aircraft predesign is possible. more...

This paper addresses the development of aircraft models for flight loads analysis in the pre-design stage. The underlying model structure consists of the nonlinear equations of motion of a free flying, flexible aircraft, as well as a model, which calculates the distributed aerodynamics over the entire airframe. Different possibilities in modelling the unsteady arodynamic interactions for pre-design purposes are explored and the effects on the loads are compared in order to assess the tradeoffs between accuracy and speed. more...