The AeroHead Airflow Template has been regenerated for a better fit with the template graphic.
A table of data was then generated, using a small CAD program to get X-Y values for the curvature-of-departure for the template.
A second order polynomial curve fit is then generated, which allows anyone wanting to make such a template, to easily do so.
Below is the data...
And here is what the data looks like in graphical format...
You can see from the graph, that the Honda Insight rear deck curvature is slightly steeper than the template.
When designing the curvature of the new tail extension, I will try to match the Aero Template over the curvature on the car.
The data clearly shows that for anyone designing an extension to the tail of the car, the biggest-bang-for-the-buck is to make the tail as long as possible, since the Y-Axis curvature is increasing with increasing length.
Trying to make the shape too short, causes the effort to be wasted because the departure angle is relatively small at short lengths.
The polynomial expression for the curve is...
y = 7.91943079843437E-04 * x^2 + .134609376182944 * x - .737888871593933
Jim