Strategy is a major talking point of an F1 grand prix weekend, with teams formulating initial plans well in advance of arriving at the track.
Strategy is ultimately dictated by tyre life, with each driver limited to 13 sets of dry rubber to last the three days. This number is made up of eight sets of the designated soft compound, three of the medium, and two of the hard.
Many factors are taken into consideration when deciding how to complete a race distance in the least possible time, and that’s where the undercut and overcut come into play.
What is an undercut?
An undercut is where a driver pits before the car(s) in front to try and gain a position.
This occurs when a team believes fresher rubber will yield more pace and create a net gain over remaining on the track by the time the other car(s) has pitted. Depending on the overarching strategy, the team may fit the same compound again, or one of the other two that are available.
This tactic is often used at tracks where overtaking is more difficult, like the Hungaroring and Singapore, and strategy is the only likely method of progressing. It is also one of the most common strategy tools for overtaking.
An example of this can be taken from the 2019 Singapore Grand Prix, when Sebastian Vettel pitted from third place before Charles Leclerc and Lewis Hamilton ahead of him. With fresh tyres, Vettel produced a quick outlap compared to the slower inlap for those ahead of him, and by the time Leclerc exited the pits Vettel was able to jump into the net race lead, which he converted into what would be his 53rd and final F1 win.
The undercut can contain risks, given it usually involves conceding track positions to car(s) behind and requires coming back out on a clear part of the track after the pitstop without being held up behind slower cars.
What is an overcut?
An overcut is where a driver remains on track longer than an immediate rival in order to try and gain a position.
Two factors can be exploited using this strategy. Firstly, if the driver remaining out on track can maintain or increase their pace compared to a rival who has pitted, they may be able to get ahead of them when they eventually take their pitstop.
Secondly, if a rival that has pitted first is unable to quickly generate tyre temperature and is slower on their out-lap, the driver yet to pit can take advantage of this by increasing the gap between the two before pitting.
This tactic is also common in Monaco, where overtaking is extremely difficult and sacrificing track position carries a significant risk.
An example of this was in the 2021 Monaco Grand Prix. Hamilton stopped on lap 29 to attempt to undercut Pierre Gasly, but was unable to get heat into his tyres. This meant that Gasly on older tyres was able to lap quicker than Hamilton on fresh tyres, increasing the gap between the two of them and staying ahead on the track. Vettel did this even more effectively, pitting two laps later and jumping both drivers.
What is a DRS train?
A DRS train is where a series of cars become locked in a stalemate where, other than the lead driver, they are all within DRS range of one another and are unable to make progress. This is because the car(s) in front also have DRS, meaning that the following drivers don’t get the benefit usually provided by DRS.
These trains are often what will spark teams into trying the undercut, so that drivers can lap in clean air and try to make a net gain once the cycle of stops has been completed.
How does the safety car affect strategy?
The safety car and virtual safety car can dramatically affect strategy with the slower lap times reducing the cost of a pitstop.
Under the VSC, the field must lap to a strict delta which is set by the FIA. This delta governs how quickly a car can arrive at certain points of the track, ensuring that the entire field slows down equally and gaps between cars are maintained. With everyone on track slowing down, the margin between the speed of those pitting to those remaining on track is smaller, meaning less time is lost in a pitstop and potentially more positions can be gained as a result.
As a reference, a green flag pitstop at the 2022 United States Grand Prix cost drivers approximately 20 seconds of lap time. Under safety car conditions, this dropped to 12 seconds of lap time – effectively giving drivers who pitted under the safety car eight seconds for free.
Therefore, teams are likely to flip race strategies in an instant if a safety car or VSC is called, as the time gained pitting under these conditions outweighs the potential time gained pitting under normal conditions or after the period that the race is suspended.
How do red flags affect strategy?
During a red flag interruption, drivers are permitted to change tyres and fix damage to their cars with like-for-like parts, meaning the obligation to run two different compounds can be fulfilled without losing any time.
This eventuality can severely alter the order with those that have already stopped, losing out as there’s no way for them to get the time lost in a pitstop back.
At the 2020 Italian Grand Prix, Gasly was notably able to climb the order through such an intervention. Having pitted just before an early safety car, to vault from outside of the points to third once other pitted ahead under the safety car, Gasly was then gifted his second free stop under a red flag triggered by Leclerc’s crash.
Coupled with Hamilton serving a penalty and overtaking Lance Stroll at the restart, Gasly moved into the lead and held on to this advantage to score his maiden victory.
The ability of a driver to complete their mandatory tyre change in such conditions remains a controversial topic.
