Optimizing a Tail for Low Drag: Part 3
Initial Testing To start the process of designing a drag-reducing tail, I threw together some boards that would give me some adjustability of their angle relative to the rearmost surfaces of my car. Then I headed out on the road for initial testing. Before you start testing, it’s important to recognize potential shortcomings and what your tests can actually show you (as well as what they can’t ). In this case, separate boards at the top, bottom, and side of my car do not replicate a complete, solid tail; rather, I’m using this test to get an idea of what might be appropriate dimensions and taper angles to start my investigations of a full tail. I’ll use these data to try and predict the drag changes from the various angles and then use those as a jumping off point to design the real tail rather than just guess at a shape. You will see people misunderstand this all the time online. Commonly, someone will make a change to their car and then use one tank’s measured gas mileage as “pr