Alright, let’s talk about yellow flags in racing, ’cause I just spent the whole afternoon trying to figure this out for a project I’m messing with.

So, first thing’s first, I started by just googling “what does a yellow flag mean in racing?”. Pretty basic, right? I got a bunch of hits explaining the general idea: caution, slow down, hazard on the track, the usual stuff.
But I needed more detail. I needed to understand the nuances. So, I dug a little deeper. Started looking at different racing organizations – Formula 1, NASCAR, IndyCar – to see if the rules were different. Turns out, they’re mostly the same in spirit, but there are some key differences in how they’re applied.
Then I jumped over to youtube, watched a bunch of race replays, specifically looking for yellow flag situations. Pay attention to what the drivers actually DO when they see a yellow flag. Do they slam on the brakes? Do they just lift off the throttle a little? How close are they to the car in front? All that stuff matters.
I watched a few videos explaining the difference between a single waved yellow and a double waved yellow. Single waved yellow means slow down, be prepared to change direction, hazard ahead. Double waved yellow means there’s a serious hazard, be prepared to stop completely.
I then decided to try and simulate this in a simple racing game I’m building. First, I needed to detect a “hazard” – like a crashed car or debris on the track. I set up a simple trigger zone in my game engine. When a “hazard” entered this zone, it triggered a yellow flag event.

Next, I had to figure out how to make the AI cars react to the yellow flag. I didn’t want them crashing into each other, or flying off the track. I experimented with a few different approaches. Initially, I just reduced their speed by a set percentage. That worked okay, but it wasn’t very realistic. The cars were still bunching up too much, and sometimes they’d still crash.
I finally decided to use a combination of things. When a yellow flag was triggered, each AI car would:
- Reduce its speed by a certain percentage.
- Increase its following distance to the car in front.
- Disable overtaking.
That seemed to work pretty well. The cars slowed down, maintained a safe distance, and didn’t try to pass each other. Of course, it’s still a work in progress. I need to refine the parameters, and add some more sophisticated behavior, like allowing the AI to gradually accelerate back to full speed when the yellow flag is lifted.
But, honestly, diving into the details of yellow flags in racing, simulating them, and seeing how it changes the dynamics, it’s kind of fascinating.