The FIA Formula One World Championship returns to the USA for the first time since 2007 this weekend with the inaugural Grand Prix at the Circuit of the Americas. The 5.516km track is set in the Texan countryside outside Austin and features corner profiles similar to the most challenging complexes ever seen on the calendar, including the Suzuka Esses and Turn 8 from Istanbul. There are also several gradient changes over a lap, particularly in sector one, which features a blind apex that will really push the drivers.
As a new event on the calendar, Renault Sport F1 will use all the tools at its disposal, including computer simulation and engine dyno running, to prepare for the GP. More than double the time is spent testing engine maps on the dyno than would otherwise be the case for a ‘normal race’; so approximately four days of dyno running and simulations.
USA Grand Prix facts and figures
Simulations predict an average speed over one lap of 196kph during the race and just over 205kph during qualifying. There are two long straights but the average speed is lowered by the high volume of low gear corners; eight of the 20 turns are taken in third gear or lower. This puts the Circuit of the Americas in a similar bracket to Valencia.
Similar to Abu Dhabi, the longest straight is not the pit straight, but rather the burst between turns 11 and 12. The straight here is 1,016m, meaning the RS27 will spend a touch over 13secs at wide open throttle. Top speed is predicted to be 314kph at the end of this straight and the engine will spend 2.5secs at max revs before braking for the hairpin of turn 12.
The second long straight is the pit straight. Both straights run in different directions so correctly selecting seventh gear will depend on wind direction on the day. Selection for the one may compromise end of straight speed for the other, so ambient conditions will be carefully monitored throughout Friday practice to find the optimum ratio.
The track is similar in power sensitivity to Malaysia, with 57% of the lap taken at full throttle during the race, and just under 60% during qualifying. The predicted lap time is around 1min 39secs.
Three hairpins triangulate the track; turns 1, 11 and 12. Revs will drop to 9,500rpm and the car speed to just 80kph. All three come after a long period of open throttle, meaning engine braking and rear stability on the apex are crucial. The exits and correct engine response from the hairpins are however equally important since they each lead back onto another straight.
Fuel consumption is one of the highest of a season over one lap, similar to Abu Dhabi. The lower temperatures of Austin offset its relatively high altitude and change of gradient, but low ambient humidity and the twisty first and last sectors where the driver is constantly on and off the throttle increase consumption. The starting fuel load will be one of the heaviest of the year, on a par with Abu Dhabi and Melbourne.
There is a real buzz about the Circuit of The Americas. It’s a very enjoyable layout with a couple of good opportunities for overtaking, some long, fast, sweeping ‘S’ bends and a few really satisfying, high speed changes of direction similar to the ‘Becketts’ complex at Silverstone. The first corner is also quite special and it will be interesting to see it when people are dicing for position in the race. It’s an enjoyable layout for a racing driver and also fantastic for the fans as the viewing areas are very well placed to catch all the action; of which there should be plenty!
Rémi Taffin, Renault Sport F1 head of track operation
Going to a new track always presents a new set of challenges as we rely heavily on simulations conducted in the dyno and on various computer modelling software. The accuracy of the models is such that we can gauge starting gear ratios, fuel consumption over one lap and a basic torque map, but nuances such as the kerbing, the abrasiveness and the undulations of the track will all need to be assessed on site.
The first sector starts with a low speed hairpin that will require good engine braking and response on the exit since it opens out to a flowing sequence of turns that have characteristics of the Maggotts-Becketts complex in Silverstone or the Esses in Suzuka. This turn is also blind, so the driver will need to ‘feel’ the corner and have the confidence that the car will behave as he wants. The next sector will be a fantastic challenge for drivers, and also for engine engineers as this type of complex is the hardest to map! The average speed through this sector will be around 210kph in fifth or sixth gear with the revs no lower than 15,000rpm. The internals of the engine will also be subject to high lateral g-forces as the driver rapidly switches direction.
A high percentage of sector two is given to the long straight, one of the longer straights on the calendar at just over a kilometre. Despite its length it’s one of the easier parts of this track; it’s sector three that is going to present the hardest challenge as it includes corners similar to the most challenging corners on the calendar; the stadium in Hockenheim and Turn 8 in Istanbul! This will be one of the sectors we will work the hardest on when we arrive.
What you can’t see from the track map is that there is a lot of undulation change over the lap, very similar to India. This will put an extra strain on the engine internals as the lubricants rise and fall within the systems over the crests and dips, but we do not expect it to be a particular concern as we already have plenty of experience on this type of track from Spa and India this year.