Generic CAD for Aircraft Design

Aircraft Design with free generic CAD tools

FreeCAD FreeCAD is a parametric 3D modeler. Parametric modeling allows you to easily modify your design by going back into your model history and changing its parameters. FreeCAD is open source (LGPL license) and completely modular, allowing for very advanced extension and customization.
DraftSight DraftSight lets professional CAD users, students and educators create, edit and view DWG files. DraftSight runs on Windows®, Mac® and Linux.
SketchUp A user friendly tool to quickly model 3D ideas. Not for engineering drawings.
LibreCAD LibreCAD is a fully comprehensive 2D CAD application that you can download and install for free. It runs on all major operating systems, including Microsoft Windows, Mac OS X and Linux (Debian, Ubuntu, Fedora, Mandriva, Suse ...).
QDAD QCAD is a free, open source application for computer aided drafting (CAD) in two dimensions (2D).
HeeksCAD HeeksCAD Imports solid models from STEP and IGES files. Draw construction geometry and lines and arcs. Create new primitive solids, or make solids by extruding a sketch or by making a lofted solid between sketches. Modify solids using blending, or boolean operations. Save IGES, STEP and STL. Printer plot the 2D geometry or to HPGL. Import and export dxf files; lines, arcs, ellipses, splines and polylines are supported.
NaroCAD NaroCAD is a fully fledged and extensible 3D parametric modeling CAD application. It is based on OpenCascade. The goal of this project is to develop a fully fledged and extensible 3D CAD software based on the concept of parametric modeling of solids, comparable to well known solutions.
BRL-CAD BRL-CAD is a powerful cross-platform open source solid modeling system that includes interactive geometry editing, high-performance ray-tracing for rendering and geometric analysis, image and signal-processing tools, a system performance analysis benchmark suite, libraries for robust geometric representation, with more than 20 years of active development.
OpenFX OpenFX is an Open-Source 3D modeling, animation and rendering suite created by Dr. Stuart Ferguson. Requires a Win32 platform.