After the weekend in Austin, the Formula 1 circus heads south of the United States border for the Mexican Grand Prix at Autódromo Hermanos Rodríguez in Mexico City.
The 4.304-kilometer (2.674-mile), 17-turn circuit has hosted Formula One since 1963, but in preparation for Formula One’s return in 2015 after a 22-year hiatus, it was completely revamped.
Noted track designer Hermann Tilke penned the new layout, which followed the general outline of the original course.
The entire track was resurfaced, with new pit, paddock and spectator stands constructed. The most notable changes from the old layout to the current version were an added sequence of corners comprising turns one, two and three, along with a revised set of corners through the Foro Sol baseball stadium, which was built inside the famed and feared Perlatada corner, which serves as the track’s final turn.
The new asphalt made for a slippery surface in 2015 and despite another year of weathering, it remained slick in 2017. Even as the refurbished track readies for its fourth year of Formula One action, drivers and teams alike expect grip to be elusive.
The smooth pavement is one factor, but Mexico City’s notoriously thin air is another significant contributor.
Sitting 2,200 meters (7,218 feet) above sea level, Mexico City’s high altitude means there is less downforce on the cars. To compensate for this, teams run more downforce than they would at similarly fast tracks like Italy’s Autodromo Nazionale Monza and Azerbaijan’s Baku City Circuit. But with top speeds in the neighborhood of 370 kph (230 mph), teams have to compromise between straight-line speed and the downforce necessary to push through the track’s corners.
Cooling is another issue facing teams in the Mexican Grand Prix. The thinner air means the turbo has to spin at a higher rate to inject more oxygen into the engine, and with the brakes being used for approximately 21 percent of the race’s 71-lap duration, keeping those brakes cool adds another degree of difficulty.
Focus points Altitude. The Autodromo Hermanos Rodriguez is situated at 2,200 metres, which is three times higher than F1’s next highest track (Interlagos in Brazil). The thinner air affects the cars in three significant ways. First, they produce less downforce. The cars run maximum downforce, yet they produce less aerodynamic grip than at Monza. Second, the internal combustion unit produces less power because there’s 75 per cent less oxygen than at sea level and, third, it’s harder to cool the car.
Most demanding section The Stadium (Turns 13-16). This is the slowest section on the lap and a lot of time can be lost if traction or turn-in are a problem. It’s easy for the drivers to lock the unloaded front tyre on the approach to Turn 13 and they have to be progressive with the throttle, or risk snap oversteer.
Unique difficulty Aerodynamics. The thin air allows cars to run similar wing levels to the Singapore Grand Prix, yet they produce 10 per cent less downforce than at Monza – the lowest downforce track of the year. As a result, the cars produce very little drag and are spectacularly quick along the 1.3km/0.8-mile pit straight. The drivers are on full throttle for 15s and top speeds peak at 354km/h (220mph) just prior to the braking zone.
Race Engineer’s Lowdown
Braking The cars spend 16s per lap on the brakes. The hardest deceleration is into Turn One, where the cars slow from 354km/h (220mph) to 106km/h (66mph) in just 70 metres, with a peak longitudinal force of 4.2g. The high altitude makes brake cooling one of the trickiest engineering conundrums of the season.
Power The cars use 1.4kg of fuel per lap, with 47 per cent spent on full throttle.
Aero High downforce. The cars run maximum downforce yet produce less aerodynamic grip than at Monza, due to the thinner air at high altitude. The reduced drag from the cars results in some of the highest top speeds of the year along the pit straight.
Statistics for Sunday’s Mexican Grand Prix at the Hermanos Rodriguez circuit in Mexico City:
Lap distance: 4.304km. Total distance: 305.354km (71 laps)
2017 pole: Sebastian Vettel (Germany) Ferrari One minute 16.488 seconds.
2017 winner: Max Verstappen (Netherlands) Red Bull
Race lap record: One minute 18.785 seconds (Vettel, 2017)
Start time: 1310 local (1810 GMT)
Lewis Hamilton will take his fifth world championship with two races to spare if the Mercedes driver scores five points, which means finishing at least seventh.
The Briton is 70 points clear of Ferrari’s Sebastian Vettel, who must win all three remaining races to have any chance.
Title-clinching scenarios: 1. Hamilton champion if he finishes in the top seven, regardless of what Vettel does. 2. Hamilton champion if Vettel fails to win.
Mercedes are 66 points ahead of Ferrari in the constructors’ championship and on course to wrap up the title for the fifth year in a row. They will need to score 20 points more than Ferrari to do so in Mexico.
Mexican Grand Prix
Hamilton won his fourth championship in Mexico last year and looks set to make it five this time.
Hamilton (2016) and Verstappen are the only active drivers to have won in Mexico, with the race returning in 2015 – when now-retired Nico Rosberg won for Mercedes, for the first time since 1992.
Ferrari last won in 1990 with Frenchman Alain Prost.
The race was won from pole position in 2015 and 2016.
Sunday will be the 19th time Mexico has held a championship grand prix.
The circuit is the highest altitude of any on the calendar (2,200 metres above sea level) and the pit straight is one of the longest in Formula One.
Grand Prix Victories
Hamilton has nine wins this season to Vettel’s five. Daniel Ricciardo has two, Max Verstappen and Kimi Raikkonen one each.
Hamilton has 71 victories from 225 races and is second in the all-time list behind seven-time world champion Michael Schumacher (91). Vettel, third on the all-time list, has 52.
Ferrari’s Kimi Raikkonen won in Texas, setting a record for most races between wins (113). His last previous win was in Australia in 2013.
Ferrari have won 235 races since 1950, McLaren 182, Williams 114, Mercedes 85 and Red Bull 58. Former champions McLaren and Williams have not won since 2012.
Hamilton has a record 81 career poles, Vettel 55.
Verstappen, who turned 21 at the end of September, can still become the youngest ever pole sitter but time is running out. The current youngest is Vettel, who did it at 21 years and 72 days.
Hamilton has 132 career podiums and is second on the all-time list behind Schumacher (155). Vettel has 109, Raikkonen 101.
Mercedes’ Valtteri Bottas has had seven second-place finishes this season.
Every driver on the starting grid has scored this season.
Mercedes are one pole position away from their 100th in Formula One.
The Autódromo Hermanos Rodríguez provides teams with a unique set of requirements to maximise lap time. Superficially, the track appears simple, featuring an abundance of slow speed corners and straights. However, this does not account for the challenges introduced by the fact that the race takes place at an altitude of over 2000m, leading to a reduction in air density of more than 20%.
Downforce vs Drag
Downforce and Drag coefficients are determined by a car’s configuration, and are independent of density and velocity. However, the Drag and Downforce themselves are proportional to density, therefore meaning they are significantly reduced for a given Aerodynamic set-up in Mexico. This forces teams to run maximum downforce wings in order to claw back lost downforce from altitude – even with this, drivers relate the feeling to that they experience at Monza, whereas the ideal downforce configuration of this circuit would be medium-high if situated at sea level.
Car Strengths Needed
Absolute downforce levels are important here, as is the case at tracks like Monaco, Hungary and Singapore, but Aerodynamic efficiency is still paramount along the lengthy main straight.
Strong direction change is required, most notably through Turns 7 to 11, but also in the first three corners.
Turbocharger reliability is critical – its spins up to 10% faster than is normally the case at sea level, placing extra forces through load-bearing components.
Efficient cooling is beneficial, as bodywork will require less attention in order to counteract the loss in inlet mass flow from the lower density.
Turns 4/5 – heavy braking on entry; it is subsequently up to the drivers how much they compromise Turn 4 by making it tighter such that more speed can be carried through the tight Turn 5 and on to T6.
Turn 7 – this corner initiates the most Aerodynamically dependent section on the track, where each corner affects the proceeding one, making it critical to start off with the ideal line.
Turn 16 – a good exit from this corner is critical to maximise speed down the ensuing straight to enable overtaking opportunities.
For only the third time this season, Pirelli is bringing its softest three compounds to a grand prix, with the new-for-2018 HyperSoft making its fifth appearance of the year.
In 2017, the favoured strategy was a one-stop, either US-SS or US-S. The tyres are a step softer in 2018, but as mentioned several times, better tyre management techniques mean that their degradation rates are similar to last year.
Therefore, it would be safe to assume an US-SS one-stop will be possible, and most likely the strategy of choice, given that the HyperSoft will probably suffer much earlier on in a stint due to its superior performance trading off against lower longevity.
The longest SS stint in last year’s race was around 40 laps, but this was also the case for the US, suggesting that longer SS stints could have been done if required. This would bring into play the possibility of a HS-SS one-stop, especially for those runners starting at the bottom of the top ten, who cannot reach Q3 on the US.
Both Renault and Sauber have placed a strong emphasis on qualifying, with each driver forecast to run just one set of tyres other than the HyperSoft before the race.
Mexico is not the easiest track on which to overtake, but is assisted by an extremely long main straight that features DRS and is preceded by a series of slow speed turns.
On the negative side, slipstream effects are reduced thanks to the lower air density reducing drag in the first place for the lead car, while the difficulty in cooling means that following a competitor closely for numerous laps may not be an option.
Rain is forecast for Friday afternoon, suggesting the morning session will be particularly busy as teams try to avoid a similar situation to Austin, where a lack of set-up and tyre data increased unpredictability for qualifying and the race.
Further showers are forecast for Saturday, with a decreasing likelihood throughout the day, while the race looks dry.
Given the uniqueness of the track, a pecking order is particularly difficult to devise. Red Bull have consistently highlighted this event as their most favourable after Singapore, so they would be expected to feature strongly, especially in the race.
Meanwhile, Ferrari will hope to continue the improvements made with their car balance and tyre wear in the USA, enabling them to fight Mercedes to the end of the season in the Constructors’ Championship.
Further back, the midfield will, as always, be defined by small margins. Haas will require a very competitive weekend in order to keep their hopes of fourth place alive.
Additional Sources: Reuters, Brembo, Pirelli, McLaren and Haas F1 Media