Bump Drafting

Bump drafting is a motorsport technique where one car intentionally makes gentle contact with the rear of another car to push it forward and increase both vehicles' speed.

This racing strategy works by combining two important concepts. First, the trailing car positions itself directly behind the lead car to take advantage of drafting, also called slipstreaming. This means the rear car faces less wind resistance because it's driving in the "shadow" of air created by the car in front.

Next comes the actual bump. The trailing driver carefully bumps into the rear bumper of the lead car, transferring momentum forward. This gentle push helps the front car overcome air resistance and accelerate faster than it could alone. Meanwhile, the bumping car gets pulled along in the lead car's wake, benefiting both drivers.

Bump drafting is most commonly seen in NASCAR racing, especially on superspeedways like Daytona and Talladega. These high-speed oval tracks feature long straightaways where cars run in tight packs, making the technique particularly effective for gaining positions or breaking away from the field.

The technique requires significant trust and cooperation between drivers. Both must communicate and work together, as poor timing or excessive force can be dangerous. When done incorrectly, bump drafting can destabilize the lead car, potentially causing it to spin out or crash.

Safety concerns have made bump drafting controversial in motorsport. NASCAR has periodically placed restrictions on the technique, especially during turns where cars are less stable. Some drivers and officials worry that aggressive bumping, sometimes called "slam drafting," increases the risk of multi-car accidents.

While most associated with NASCAR, bump drafting also appears in other racing series including endurance racing and karting, wherever cars run close together at high speeds and aerodynamics play a crucial role in performance.