Often wind tunnels are not a tunnel at all, but a large room with a huge fan. This is a tunnel, but there is no wind here. Aren’t we just using the wrong word? And it is precisely the lack of wind that makes this tunnel so good. One Tom Scott, who you may know from YouTube, visits the special tunnel where the aerodynamics of cars are tested. And it’s the perfect place to scrub through with a V12 Ferrari with the windows down.
The Catesby Tunnel is a tunnel that was built in 1897 as a railway tunnel. It had fallen into disrepair and in 2021 has been converted into a testing facility. The special thing is that the asphalt is completely flat when you look at the start and end point. The tunnel therefore does not follow the curvature of the earth. Quite an achievement for more than 1,000 years ago. Or is this the ultimate proof that the Earth is flat? The piece of asphalt is 2.7 kilometers long and there is a turntable at the end.
In the tunnel it is always almost the same temperature and there is no wind. Perfect conditions to test a car; because you exclude as many variables as possible. Every five meters there is a target on the wall that measures a device in the car. This way the device knows how fast the car is going, since there is no GPS signal in the tunnel.
What can you test in the tunnel?
What they’re doing in the video is a rollout test. The car accelerates to a certain speed and the equipment shows how quickly the car slows down again on its own. The car brakes a little harder if there are cameras hanging on the outside due to the air resistance. Good performance can also be measured, such as acceleration or braking, but sound insulation or engine temperature can also be experimented with.