Blue Flag with Yellow Stripe

A Blue Flag with Yellow Stripe is a motorsport warning signal that tells a driver a faster car is approaching from behind and wants to overtake them.

This flag is one of the most important communication tools between race officials and drivers on the track. When you see a marshal waving this flag at a driver, it means someone behind them is going significantly faster and needs to get past. Think of it like a "heads up" warning that lets the slower driver know what's happening behind them, since they can't always see everything in their mirrors while concentrating on driving at high speeds.

The blue flag with yellow stripe appears most commonly when a leading car is about to lap a slower competitor. In racing, when you're so far ahead that you catch up to cars that started at the same time but are now a full lap behind, those slower cars need to let you pass without fighting for position. They're not actually racing you for placement anymore, so the flag reminds them to move aside safely.

During practice and qualifying sessions, race officials use this flag more liberally. If any driver is on a fast lap trying to set their best time, and another driver is going slower ahead of them, the slower driver will see the blue flag. This ensures that everyone gets a fair chance to record their quickest lap without being stuck behind traffic.

When a driver receives this flag signal, they're expected to move off the racing line when it's safe to do so. The racing line is the fastest path around the track, so by moving slightly off it, the slower driver creates space for the faster car to pass cleanly. The key word here is "safe"—the slower driver shouldn't make sudden movements or brake unexpectedly, as this could cause an accident.

Different racing series treat the blue flag with varying levels of seriousness. In some forms of motorsport, it's considered a courtesy warning where drivers are simply expected to cooperate and show good sportsmanship. However, in Formula 1 and other top-level racing series, ignoring blue flags can result in serious penalties including time penalties or even fines. Formula 1 drivers typically have three marshaling posts (about three corners) to allow the faster car past before they face potential penalties.

It's important to understand that officials only show the blue flag when cars are not racing each other for position. If two cars are fighting for the same place in the standings, no blue flag appears—that's just normal racing. The flag specifically applies to situations where one car has already gained a significant advantage or is lapping slower competitors.

While the slower driver must facilitate the pass, the responsibility for completing a safe overtake still belongs to the faster driver. The slower driver's job is simply to be predictable and create an opportunity, not to slam on the brakes or pull completely off the track.