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What Does Delta Mean In F1? (Explained In Simple Terms)

Formula 1 is a sport that uses a lot of unique terminology. Commentators and teams don’t always explain terms because they’re used so often. If you’re new to the sport then you might be slightly confused as to what people are referring to when they talk about the delta in F1.

The delta in F1 refers to the difference between two lap times. If a driver is going slower than a reference lap time, they have a positive delta, which is measured in seconds, and tenths, hundredths and thousandths of a second. The delta is used to keep track of the driver’s pace during a session.

The delta can tell teams a lot about what’s happening to their driver out on track. It’s much more important than just seeing if the driver is slower than they were before. Below, we go into how drivers and teams use this information during qualifying and practice to improve their performance.

Why Is It Called Delta In F1?

The word delta means difference (or change), and in F1 it’s used to illustrate the time difference between two laps. The term delta is often used in Formula 1 and you may hear it from commentators, drivers, and teams during every session of the weekend.

Delta refers to the time difference between two different laps. For example, when you’re watching qualifying, the live feed will show the driver’s delta to the pole position time. If their sectors are a personal best, the delta will be green. If their sector is the fastest in the entire session it will be purple, and a yellow sector is slower than their personal best and the fastest time.

The delta is not always used to compare the driver’s laps to the fastest time though. If the driver is in the knockout zone in Q1, their delta will be compared to the driver in 16th place, since that is their target and the lap time that they need to beat to get through to Q2.

Qualifying is the session where we’ll hear most about delta times. Although it is still important in the race, we tend to look at the intervals and the gaps between cars. However, delta time might still be used to show how a driver’s laps compare to another car over a period of time.

Delta Times In Free Practice

Delta times are incredibly important in Free Practice sessions as well though. This is where the teams will be looking further into the delta times in order to get enough data for the program that they are running, especially if it’s a race simulation program.

During a race simulation, the teams will be filling their cars up with fuel and testing how far the tires can go before they begin to lose grip. This information helps them to understand what they can expect for the race on Sunday.

Teams and drivers will use their delta times to see how quickly the tires wear while they are trying to put in some consistent laps. The delta between each lap will give them an indication of how their pace will drop off during the race. For example, they might only lose a tenth of a second every five laps or they might lose half a second every three laps.

Understanding this data and how the delta changes through the stints will help them to plan their strategy for the Grand Prix. Considering the different variables involved, strategists will be able to calculate when they need to bring the car in for a change of tires and whether they need to stop more than once during the race.

What Does Positive Delta Mean In F1?

A positive delta in F1 means the driver is going slower than a given reference lap. This reference lap might be their fastest lap, and so a positive delta wouldn’t be ideal, or it may be the time they need to be above behind a virtual safety car in order to avoid getting a penalty.

The term delta on its own simply refers to the difference between two lap times. A delta can either be positive or negative, but this is where it can become a bit more confusing for many people who are new to motorsport.

A positive delta means that the driver is slower than their target lap (the target lap can either be their own personal best lap or the fastest lap of the session). With a positive delta, the driver is currently setting a lap time that is longer (and therefore slower) than their target lap. This is signified by the plus symbol next to their delta.

A negative delta on the other hand means that the driver is going faster than their target lap time. The minus symbol (often accompanied by either green or purple) shows that the driver’s current lap is taking/has taken a “smaller” number of seconds (i.e. faster) than the lap time they are aiming for.

It’s confusing to many people because of the fact that “positive” naturally means better. However, in terms of lap times a positive delta is usually worse. However, behind a virtual safety car for example, drivers must stay above a given delta in order to be going slow enough. This is a situation where a positive delta isn’t just a good thing, but it’s necessary to avoid getting a penalty.

How Are Deltas Measured In F1?

Delta times in F1 are measured very precisely. This allows teams, drivers and the fans to keep track of the progress that drivers are making out on track. Formula 1 uses three major sectors to show how the driver compares to their target lap over three different areas of the track.

Each of these major sectors are also divided into mini sectors. Every Formula 1 car has a transponder that sends a signal whenever they cross a “timing loop.” Mini sectors are split into 150 to 200-meter sections, and this is where the delta time gets incredibly interesting.

By looking at these mini sectors you can clearly see where one car is losing time to another. For example, one car might have a low downforce setup, and this will give them more speed on the straights. In this scenario, you’ll see purple mini-sectors on the longer straights of the track.

However, if another car is running a high downforce setup you’ll see where they are faster than their opposition, which would be the tighter, twistier sections of the track. Over the course of the lap, these mini-sectors will change, and it’s unlikely that the fastest lap will have all of the mini-sectors in purple.

How Do Drivers Know What Their Delta Is?

F1 drivers know what their delta is by looking at their steering wheel, which has a digital dashboard that can display their delta time. However, their race engineer will also be in contact with them over the radio, and they’ll keep them informed of their own and other drivers’ delta times.

It can be easy for us to see the driver’s delta because it’s nicely presented on the live feed with different colors. The commentators will also talk about whether the driver is going faster or slower than their target time. However, in the car it’s a completely different ball game.

Driving a Formula 1 car is incredibly difficult and it requires a lot of focus. Drivers can’t constantly be updated by their team on how their lap times are progressing. While the team can give them live updates, it can often be distracting for the driver while they are focused on driving to the best of their ability.

Modern Formula 1 cars have a digital dashboard that will show them what their delta is while they’re out on track. Drivers can program their dashboard to indicate which lap they are targeting, so it’s not always set to show the delta to their personal best lap times.

When the driver crosses a sector line the delta will flash on the screen for a few seconds. This allows the driver to glance at the screen and see their delta in an instant so they’ll know if they have improved their lap times or not. This method is the least distracting for the driver as they do not have to look at their steering wheel, and can see the delta if they want to.

Safety Cars, Virtual Safety Cars And Delta Times

Due to the advancement of this technology and the ability to monitor a driver’s delta times every 150 meters on the track, the Virtual Safety Car (VSC) was brought in during the 2015 season. The VSC neutralizes the race without bringing out a full safety car. This means that all drivers keep their positions, gaps, and there’s less interference in the race.

The VSC is a game changer in Formula 1, and it’s all thanks to delta times. As soon as the VSC is deployed, drivers need to reduce their speed by about 30-40% and they will be told to keep a positive delta. This means that they need to ensure that their lap times are always slower than before.

With the delta positive order in place, drivers must make sure their delta is below the virtual safety car’s at least once in each marshalling (or mini) sector – these are the sectors measured every 50 meters. If they don’t, then the driver will be penalized for speeding under the VSC.

During a VSC the delta time on the driver’s digital dashboard becomes the lap times they are supposed to be setting at a 30-40% reduction in speed. Drivers will try to keep their delta as close to zero on this time to avoid losing time to other cars. Ideally, they won’t be going slower than they need to.

Final Thoughts

Delta is a term that is used very often in F1, but it’s often not fully explained during the live feed. The delta simply refers to a difference in lap time, which can be important for measuring performance, gathering data, or abiding by the virtual safety car rules.