# vtol aerodynamic unit and cp, area

This post is a wiki. Anyone with karma >75 is welcome to improve it.

<plugin name="lifting_surface" filename="libLiftDragPlugin.so">

    <!-- taken from the lift curve figure -->
<!-- alpha_0 is 5 degrees -->
<a0>0.08727</a0>
<!-- alpha_stall is 19.3 degrees -->
<alpha_stall>0.3368</alpha_stall>
<!-- slope of the lift curve to the left of the stall angle -->
<cla>5.418</cla>
<!-- slope of the lift curve to the right of the stall angle -->
<cla_stall>-2.1419</cla_stall>

<!-- below are just random values in this example -->
<cda>0.0</cda>
<cda_stall>0.0</cda_stall>
<cma>0.0</cma>
<cma_stall>0.0</cma_stall>
<area>3</area>
<fluid_density>1.2041</fluid_density>
<forward>-1 0 0</forward>
<upward>0 -1 0</upward>
<cp>0 0 1</cp>