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How Are F1 Lap Times Measured? (Full Explanation)

Formula 1 is the fastest sport on the planet with some incredibly tight competition. Sometimes the competition can be so close that two cars can be within thousandths of a second of each other. But this begs the question of how F1 lap times are measured in the first place.

F1 lap times are measured using highly advanced transponders. The transponders transmit radio waves to timing loops that are placed all around the circuit. As soon as the car passes over the timing loop their lap time is recorded to the accuracy of 1 ten thousandth of a second.

This technology has been developed over time, and in the past stop watches had been used to (inaccurately) measure a Formula 1 car’s lap time. Below, we take a closer look at just how accurate F1 lap times are, and how they’re measured to such a high degree of accuracy.

How Do They Measure F1 Lap Times?

You might be thinking that Formula 1 needs to use complicated systems in order to accurately measure their lap times. However, the timing systems in Formula 1 have remained largely unchanged for the past few decades.

Each Formula 1 car is fitted with a transponder the size of a match box, which sends out radio waves. Each car is on a different wave length so that none of them interfere with one another and we can get an accurate lap time from each driver.

Timing loops are the “receivers” and these are made up of wires that run across the width of the circuit. The wires are encased in silicone for protection, and they are kept about an inch underneath the tarmac.

The timing loops are placed in intervals around the circuit, usually either 150 or 200 meters apart. The data is sent back to the control center which is then sent to the live timing screens. The intervals in the timing loops give us a clear indication of where each car is at any given time.

When Were Transponders Introduced In Formula 1?

Transponders made their way into Formula 1 in the late 1980s. These are similar to the ones we see today and they had the same level of accuracy in terms of measuring cars’ lap times.

However, the difference between modern timing systems and ones used in the 1980s, 1990s and even during the 2000s, is that the timing loops are much more frequent on modern racetracks. This gives us a more accurate representation of the car’s lap time. This came with the advent of “mini sectors” alongside normal sectors.

What Is A Sector In F1?

A sector in F1 is part of the track that’s used to help fans and teams understand where certain cars are fastest. F1 tracks are split into three main sectors, and various mini sectors within those three. Teams use timing data to understand where their car is fast and where it’s underperforming.   

Have Mini Sectors Improved The Sport?

Mini sectors have vastly improved the sport for viewers, teams and drivers alike. Firstly, the mini sectors allow fans, teams and drivers to analyze exactly where one driver might be faster than another. We can also see exactly how much faster one driver is through a set of corners compared to another. This helps us to identify exactly where teams and drivers are faster than others.

Mini sectors have also helped in terms of monitoring the gap between drivers during the course of a race. In the old days, fans, teams and drivers had to wait to cross one of the three main timing loops before they got to see their interval to the driver ahead or behind. In modern Formula 1 though the gap is measured every 150-200 meters, which means it is constantly up to date at any given time.

Finally, mini sectors have helped fans, teams and commentators to identify when a driver has had a problem on track even when they’re not on screen. If a driver suddenly drops off the timing sheets, it’s likely that they have spun, crashed or had reliability issues with their car. This became far more accurate and reliable with mini sectors.

What If The Transponder On A Car Breaks?

Luckily the team behind Formula 1 timing solutions, TAG-Heuer, have considered this possibility and came up with a solution. Just like with any piece of technology, a transponder is not always reliable in the sense that it could be faulty or broken.

As a backup system, each sector line, as well as the start finish line, has an infrared camera that is able to identify and register each car on track. Should the transponders fail, this system can time the cars accurately across a lap.

On top of that, another backup system is put in place. Timer-linked video cameras are also placed on the sides of the circuits as well as on the cars. These are able to time the car as it goes through its entire lap.

How Accurate Are F1 Lap Times?

Formula 1 lap times are incredibly accurate. They need to be in order to make the sport as fair as possible. F1 lap times are measured to within 1 thousandth of a second, or 0.001 seconds. Often all that separates two cars in qualifying is measured in the hundredths or thousandths of a second.

The system can measure to a ten thousandth of a second as well, however, it’s rare that we see the ten thousandths of a second being used, and the TV timing screens only show into the thousandths. On some occasions we have even seen identical lap times being posted from different cars, but this hasn’t happened in qualifying in a long time.

What Does A Thousandth Of A Second Look Like?

To give you an idea of what 0.001 of a second looks like, it’s about 7 centimeters, or 2.5 inches, difference between two cars crossing a line. TAG-Heuer actually released an equation you can use to calculate the distance between cars based on the gap between them. The equation is as follows:

D = S x T/36

Where D is the distance in centimeters, S is the speed of the car in kilometers per hour and T is the gap between two cars in thousandths (.001) of a second.

What Does Interval Mean In F1?

Interval in F1 refers to the gap between two cars on the timing screens. You’ll often see the person leading the race at the top with no time next to them, and then every car from second place and beyond with a number next to their name, showing how far behind the leader they are.

In Formula 1, data, statistics and numbers are everything. During the course of the race, a lot depends on the gap between drivers. Understanding the gap between drivers can allow you to see whether a driver is catching the car ahead of them, being caught by the car behind them, or even where they would rejoin the race after a pit stop.

How Cars Are Performing

However, there’s even more to it than that. You can even take an overall look at a driver’s performance to see how they are managing their pace and whether they will be able to keep their position until the end of the race or present themselves with an overtaking opportunity. Comparing their previous laps and forming a pattern along with the drivers around them is the best way to do this.

While you’ll often see the interval shown as the gap between the leader and each car behind them, further on in the race these gaps become larger as slower cars slip further back. This is when you’re likely to see the intervals between each car rather than between P1 and P7 for example, as this is more relevant to understand where each driver is.

Understanding The Intervals In F1

For example, if by lap 20 some cars are being lapped, they may be shown on the timing screens as “+1 lap” rather than a number. But you also might see the gap between P1 and P2 as 0.050 seconds, the gap between P2 and P3 as 6.089 seconds, and then the gap between P3 and P4 as 0.032 seconds.

This might appear to be confusing, as how can the gap between P1 and P4 be smaller than that between P1 and P2? The answer is that the timing screen is now showing the gaps between each car rather than the interval to P1, as this is more relevant for understanding who is within overtaking range of the cars in front etc.

How Are F1 Time Intervals Calculated?

In Formula 1 the interval or gap between cars is measured in seconds rather than distance. This is simply because it is easier to measure instantaneously, and it gives a more accurate representation of how far behind a car is from another one.

The interval is measured using the timing loops and the various sectors and mini sectors on track. Whenever a car passes over a timing loop, a system will begin to time how long it takes for the next car to pass the exact same spot.

Once the next car passes the same spot, the interval is established. For example, if the race leader has a five second gap to the car behind it means that from the moment the leader crossed a timing loop (for example the start line) it took five seconds for the next car to cross the same point.

On the next lap, if the leader crosses the line and the next car crosses the line 4.5 seconds later, it means that the car behind has caught up by half a second. This method of measuring intervals removes the need for confusing distance measurements and brings in a standard measurement across all forms of motorsport.

Final Thoughts

Formula 1 uses high tech transponders on each car to measure their lap times to the accuracy of 1 ten thousandth of a second. The timing loops are placed 150-200 meters apart, giving us a constant update on the car’s performance over the course of a lap.