Vehicle Sketch Pad (VSP) is a parametric geometry modeling tool that is intended for use
in the conceptual design of aircraft developed by NASA and provided free for public use. The intent of this software is to rapidly model aircraft configurations without expending the expertise and time that is typically required for modeling with traditional Computer Aided Design (CAD) packages.
It is easy to use, fast and the great number of geometric parameters provides huge freedom in design. The following airplane was generated in less than 10 minutes by the author of this blog with no previous experience in the software.