Tuesday 20 September 2011

Singapore race strategy a knife edge

This weekend’s Singapore Grand Prix will be absolutely fascinating from a strategy point of view. Find out how some teams will try to do the race with only one stop, how much effect the Safety Car can have on the outcome and check out a new feature: the League Table of Team’s Pit Stop Performance; there are some surprises here!
Contents – The Key Strategy considerations
• Track characteristics
• Form guide
• Weather forecast
• Likely tyre performance
• Number and likely timing of pit stops
• Chance of a safety car
• Recent start performance & Pit Stop League Table

Track characteristics
Marina Bay, Singapore – 5.073 kilometres. Race distance – 65 laps = 309.3 kilometres. 23 corners in total.. Street circuit around Singapore’s Marina Bay area.
Aerodynamic setup – High downforce. Top speed 305km/h (with Drag Reduction System active on rear wing) – 290km/h without.
Full throttle – 43% of the lap time (low). Total fuel needed for race distance – 165 kilos (very high). Fuel consumption – 2.5 kg per lap (ave/high)
Time spent braking: 21% of lap. Number of brake zones – 16. Brake wear- Very high. Toughest race of season for brakes as no cooling opportunities.
Loss time for a Pit stop = 24 seconds (very high)
Total time needed for pit stop: 26 seconds (very high)
Fuel effect (cost in lap time per 10kg of fuel carried): 0.35 seconds (high)
In just three years the Singapore Grand Prix, F1’s only night race, has established itself alongside Monaco as one of the two most important races on the calendar for the sport, the teams and sponsors.
But the race on the Marina Bay Circuit is also one of the longest and toughest of the year for cars and drivers. The race can last up to two hours and with high temperatures , humidity and constant braking and turning, it is a real hardcore marathon. There have been internal discussions among teams and administrators about possibly shortening the race.
It is also one of the hardest races of the season for the brakes, not because of big stops from high to low speeds, but because of the frequent brake use and no straights to for the brakes to cool. This places an extra strain on the tyres as the red hot brakes inside the wheels cook the tyres from the inside.
As the track is at sea level, the air pressure is higher, the air is more dense and this means that the fuel consumption is higher. The stop and start nature of the track further adds to this. So the cars start heavier than at many places with 165 kilos of fuel on board -15 kg more than the average. This adds to the punishment of the tyres in the early stages of the race.
We are likely to see plenty of new development parts on the cars this weekend. This will be the last race at which we see teams bring significant upgrade packages to their cars. As the first of a series of six flyaway races to close the season and with the championship more or less decided, there will only be some minor development steps after this.

Form Guide
The Singapore Grand Prix is the 14th round of the 2011 FIA F1 World Championship. With Sebastian Vettel winning in Spa and Monza, he is in a position to be crowned world champion for the second consecutive season if he wins here with neither Fernando Alonso or Jenson Button on the podium.
Vettel and Alonso battled for the win at Marina Bay last season in a close fight throughout the race, which was won by Alonso, the only two time winner here.
Amazingly, Red Bull’s 100% record in qualifying this season remains, with only seven rounds to go, could they possibly go a whole season owning pole position?
As far as drivers’ and teams’ form at Singapore is concerned; Alonso won the race in 2008 with Renault and 2010 with Ferrari, Lewis Hamilton won the 2009 edition for McLaren.
Weather Forecast
The weather forecast for this weekend is for high temperatures, around 31 degrees, with thunderstorms forecast for each day and a 60% chance of rain. Given the frequency of evening rain in the region it is amazing that it has yet to affect the Singapore Grand Prix.

Likely tyre performance and other considerations
Pirelli tyre choice for Singapore: Soft (yellow markings) and supersoft (red markings). This combination was seen in Monaco, Montreal and Budapest.
In Singapore the great challenge is to look after the rear tyres, which get damaged by the constant stopping and accelerating at the circuit’s 23 corners. Meanwhile the fastest corner on the circuit is taken at only 170km/h so it is difficult for driver to get energy into the front tyres and get them ‘switched on’. Add in the factor of the red hot brakes cooking the tyres from the inside and tyre management becomes a huge challenge.
In Budapest the Pirelli supersoft tyre was expected to last 20 laps, but after the track was cleaned by rain before the race they only went for 14 laps. The Marina Bay circuit ramps up in grip over the weekend, but teams will closely monitor its performance in Friday and Saturday practice to see how far they can push it.
After the controversy over camber angles in Spa and the subsequent FIA edict in Monza, Pirelli have relaxed their recommendation for Singapore and teams can run up to 4 ¼ degrees camber. There are no sustained high wheel rotation speeds to worry about so blistering will not be a problem. The edict in Monza would have been very hard to enforce, incidentally, because there is a big difference between when the car is stationary and when it is at speed and any team on the wrong side of the FIA would have appealed. In that process it would have been up to the other teams to prove they would have complied.
Number and likely timing of pit stops
This is set to be a fascinating race, as the strategy models say that the most attractive way is to make only making one pit stop; the time lost from making a pit stop is huge in Singapore at 26 seconds. This will be very hard to achieve for cars which do not have a new set of supersoft tyres – ie drivers in the top ten who will be obliged to start on the supersofts on which they qualify.
Teams like Sauber and Toro Rosso and even Ferrari, which are gentler on their tyres, could have a strong result here. Qualifying outside the top ten, it is not hard to envisage a Sauber or Toro Rosso starting on a new set of soft tyres and making one stop for a new set of supersofts. The chance of a Safety Car is very high (see below) and six or seven laps behind the safety car would be a real bonus to one stoppers, extending the tyre life.
Safety cars can make or break your race depending on when they fall. They are bad news for anyone attempting a multi-stop strategy, but with the long pit lane at Marina Bay this isn’t likely.
But should a safety car fall at an opportune moment for a driver aiming to make a two stop strategy, it could be ideal. The front runners are likely to be planning to divide the first half of the race into two stints on supersoft with a switch to softs for the remainder of the race, but will stay flexible in case a Safety Car helps them out.
Chance of a Safety Car
The chance of a Safety Car at Singapore is very high. There has been at least one Safety Car at every Singapore GP so far with an average of 6.7 laps spent under Safety Car. This will further encourage teams hoping to one stop in the races.
Recent start performance
Starts are a critical part of the race and strategy can be badly compromised by a poor start, while good starts can make strategists change their plans in the hope of a good result.
Michael Schumacher is having a great year off the start line, with another great start in Monza gaining four places. In total he has gained 35 places on the first lap this season, but he has also lost 14 giving him an aggregate gain of 21 places.
The importance of the start is also well illustrated by Jaime Alguersuari in Monza – he gained seven places from 18th on the grid and got ahead of his team mate Buemi and Bruno Senna. He was able to carry this through to the chequered flag to record a career best 7th place.
As far as 2011 start performance is concerned drivers have gained (+) or lost (-) places off the start line this season on aggregate as follows:
Gained
+21 Schumacher *
+19 Buemi #
+16 Glock
+13 Liuzzi
+9 Ricciardo
+8 Alonso***, Kobayashi**,
+6 Trulli, Kovalainen, Heidfeld ******,
+5 Di Resta,
+4 Massa
+3 D’Ambrosio
Held position
-
Lost places
-2, Chandhok
-4 Hamilton, Vettel
-5 Alguersuari####
-9 Sutil ##
-10 Button,
-11 Rosberg*****, Maldonado
-12 Senna
-13 Perez ###
-15 Petrov,****
-18 Barrichello
- 22 Webber
* Schumacher had one bad start in Australia, losing 8 places but since then has been the season’s outstanding starter. He gained 9 places in Spa and four in Monza.
** Kobayashi lost 10 places in Spain, prior to that he had gained 8 in 4 starts.
*** After losing places in the first three races, Alonso has reversed that trend. His starts in Barcelona and Monza were outstanding.
**** Petrov had a good record until he lost 4 places at the start in Valencia. He was on a +2 balance before Monza where he was taken out at the start.
***** Rosberg lost four places at the start in Silverstone and was on a +6 balance before Monza where he was taken out in the first corner
****** Heidfeld had gained 20 places but lost 12 at the start in Germany
******* Di Resta had consistent start form and gained 7 places in the first nine races, but lost 12 at the start in Germany.
# Buemi made up nine places at the start in Hungary having started 23rd on the grid
## Sutil had a positive start balance until Hungary where he lost 12 places at the start
### Perez lost nine places off the start in Hungary.
#### Alguersuari was doing well with a +6 record prior to Spa, where he was hit by another car and lost 18 places. In Monza he gained 7 places at the start.
Bonus Feature – Pit Stop League Table
Of course good strategy planning also requires good pit stop execution by the mechanics. We have seen tyre stops of under three seconds this season. Here, with thanks to our friends at Mercedes GP Petronas is the league table of average of the stops made (taking out all anomalies)
The table allows for an average amount of time for the loss time of travelling down the pit lane: for example Monza was 17.6 secs:
1. Red Bull – 21.81
2. Mercedes – 21.94
3. McLaren – 22.06
4. Ferrari – 22.36
5. Force India – 22.48
6. Lotus – 22.71
7. Renault – 22.72
8. Sauber – 22.81
9. Williams – 22.96
10. Toro Rosso – 23.05
11. Virgin – 23.65
12. HRT – 25.14
The things which stand out here are a) Force India and Lotus punch well above their weight in terms of pits stop performance compared to car performance and championship position. Look at the gap in performance between Lotus and the other new teams; b) Red Bull and Mercedes are consistently the fastest at pit stops; c) remember that the speed of a stop is not just about the pit crews, it is also about the drivers hitting their marks. It’s about discipline as a team.
The UBS Strategy Briefing is written by JA on F1 with input and data from strategists and engineers from several leading F1 teams.