Even just seven or eight years ago, a lot of misinformed enthusiasts saw a bumper canard or dive plane as a gay add-on to a car, or something that was needed only if you went 200 mph all time. But anyone who has been to a time attack or grip event lately will have seen these little winglets attached to the side of the front bumper. They are now seen as an essential component in fine-tuning the aerodynamics of a race car, and even high performance cars like the R-35 GTR show a small vestigial protrusion on their front bumper that looks like a canard.
The word canard is also the name for a type of duck, which is what these aerodynamic devices reminded onlookers of when they first saw it. Originally used as airflow control surfaces on airplanes, canards as used in the aeronautic environment were used to direct airflow towards the main wing or as a supplementary control for longitudinal maneuvers. They are also used in large aircraft to help dampen buffeting in low altitude runs. And although they don’t look as sexy (and are in fact rarely seen), these devices are also used as controls in submarines and are known as dive planes.
Using dive planes in cars isn’t just a matter of sticking these triangular things on your car. As applied to cars, canards or dive planes have two effects. The first obvious one is that they increase downforce. The second is that they introduce vortices on the side of the car which go down the sides of the vehicle as it travels at speed. But if you think that the added turbulence is bad for the car, it in fact has a positive effect. The vortices effectively create a curtain which prevents high pressure air from intruding into the underbody of the car, where a low-pressure region would have been generated by a combination of the front air dam and the rear wing and diffuser. Upsetting this balance would reduce downforce, which isn’t what you want in your car when you’re travelling at speed.
So, although canards (or winglets, or dive planes – take your pick) looked like gay add-ons to enthusiasts in the past, these small aero devices play a critical part in tuning the aerodynamic balance of a car. And even in “amateur” motorsport, things have become so competitive that even a small advantage can spell the difference between a podium place and watching with the crowd.