Sweeper

A sweeper is a long, fast corner on a racetrack with a gentle curve that allows drivers to maintain high speeds, or alternatively, an official support vehicle in rally racing that follows competitors to ensure safety and collect timing information.

In circuit racing, a sweeper corner is the opposite of a tight hairpin turn. While hairpins force drivers to slow down dramatically, sweeper corners have a large radius that lets cars flow through at much higher speeds. Think of it like the difference between navigating a sharp 90-degree turn in a parking lot versus gently curving along a highway on-ramp.

Driving through a sweeper requires a different technique than slower corners. The key is maintaining smooth, controlled movements throughout the entire turn. Drivers must find the perfect racing line—the fastest path through the corner—while carefully balancing their steering input and throttle control. Getting this balance right is crucial for maintaining speed.

One common mistake in sweeper corners is entering with too much speed, which causes the front of the car to push wide in a condition called understeer. This forces the driver to miss the ideal apex, or inside point, of the corner. Conversely, entering too slowly causes the front tires to grip too early, also compromising the apex and costing valuable time on the exit.

Famous examples of sweeper corners include Turn 6 at Circuit of the Americas in Texas and Turn 14 at Road America in Wisconsin. These high-speed bends are often thrilling for spectators because cars remain at impressive speeds while drivers demonstrate their skill and precision.

In rally racing, the term sweeper has a completely different meaning. A sweeper car is an official support vehicle that travels the entire rally route behind all competing cars. This vehicle serves as a safety net for the event, ensuring that no competitor is left stranded or unaccounted for on the course.

The sweeper car crew has several important responsibilities. They confirm that every competing car has safely completed each stage of the rally, watching for any breakdowns, crashes, or mechanical problems. If they encounter a stopped car, they can provide assistance or coordinate rescue efforts.

Additionally, the sweeper crew collects official paperwork from timing officials stationed throughout the course, including time cards and damage reports. This ensures all documentation reaches rally headquarters for official results. Sweeper cars typically display a single checkered flag on the door panel for easy identification.

The sweeper crew maintains constant radio contact with rally headquarters throughout their journey, reporting any incidents, problems, or delays they encounter. This communication system helps organizers respond quickly to emergencies and keep the event running smoothly. Once the sweeper car completes a stage, officials know that section of the course is clear and all competitors are accounted for.