Wing in airflow. Showing angle of attack.
User <a href="https://en.wikipedia.org/wiki/User:Theresa_knott" class="extiw" title="en:User:Theresa knott">Theresa knott</a> on <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a>; remade to SVG by <a href="//commons.wikimedia.org/wiki/User:Petr_Dlouh%C3%BD" title="User:Petr Dlouhý">User:Petr Dlouhý</a>
CC BY-SA 3.0
Original (png) image was draw by <a href="https://en.wikipedia.org/wiki/User:Theresa_knott" class="extiw" title="en:User:Theresa knott">Theresa knott</a> using the drawing tools that come with <a href="https://en.wikipedia.org/wiki/Microsoft_Word" class="extiw" title="en:Microsoft Word">Microsoft Word</a>. See <a href="https://en.wikipedia.org/wiki/Wikipedia:How_to_draw_a_diagram_with_Microsoft_Word" class="extiw" title="en:Wikipedia:How to draw a diagram with Microsoft Word">en:Wikipedia:How to draw a diagram with Microsoft Word</a> for advice on how to draw diagrams like this.