The use of flags has been part of F1 since its first race in 1950, and they were used in other forms of motor racing before that. Travelling at 200 mph means you're often reliant on marshals ...

Automobile racing became a fixture in Utah decades before ... Rocky Moutain Raceways mascot Rocket holds up two flags as a pair of jet car racers test their engines before a drag race at the ...

To throw a caution flag or not on last-lap crashes? A string of tests of the policy — with inconsistent choices — has NASCAR in a pickle.