File:Ayaks plane from Paul A. Czysz Future Spacecraft Propulsion Systems.png

Scheme of the Ayaks plane from Paul A. Czysz Future Spacecraft Propulsion Systems: Enabling Technologies for Space, Springer, 2006, ISBN 3540231617

Based on the scheme drawn by the authors of the plane for the promotional reasons

Fair use rationale for Ayaks
I believe using the scheme on the Wikipedia servers to illustrate the Ayaks article constitutes fair use as defined by the copyright law of the United States because: Alex Bakharev (talk) 06:38, 26 December 2007 (UTC)
 * This is a promotional material released by the developer to illustrate the concept.
 * The material is used in the article to discuss the conception
 * The quality of the scheme is law, it does not allow to build the aircraft
 * Since the aircraft is not built yet and the plans are copyrighted obtaining of free substitutes is impossible