The Summer Shutdown has ended and F1 is going racing again!
The Spa Francorchamps circuit, home of the Belgian GP, has a very strong history in F1, going right back to the first year of competition in 1950 and is one of the drivers’ and engineers’ favourite tracks. It has the longest lap of any modern F1 track at over seven kilometers.
Last year one of the key issues for teams to decide in their strategy planning was whether to go for a low down force set up, with less wing, to help straight line speed in sectors one and three, or whether to go for more down force to help with sector 2. Gearing was also important and several drivers found themselves with a less than ideal combination of gearing and down force, with the result that they were hitting the rev limiter on the Kemmel Straight and losing speed.
All of this led to a mixed up grid with two Saubers and a Williams at the front, Red Bull struggling for pace, with Sebastian Vettel in 10th place on the grid and Lewis Hamilton down in seventh with the wrong set up, tweeting his team mate’s (correct) set up sheet in frustration.
Spa provides one of the sternest tests of an F1 engine, with around 70% of the lap spent at full throttle. The run from La Source hairpin to the braking point for Les Combes features 23.5 seconds of constant full throttle. For this reason teams rotate the engine use from their allocation of eight engines per driver for the season, so they do not use the same engine at the next race in Monza, another tough one on engines.
Spa these days, with high downforce cars and DRS wings, is flat out for most of the lap.
Qualifying is not hugely significant to final race result; the pole sitter has only won the race four times in the last 12 years. Overtaking is not a problem at Spa and the DRS wing makes it very straighforward anyway.
In addition to the long straights there are quite a lot of high G-force corners, similar to Silverstone, which take their toll on the tyres. This year Pirelli has brought medium and hard tyres, which will be very durable. After the dramas of Silverstone and the tyre failures, Pirelli will want a quiet, conservative weekend in Spa.
Spa Francorchamps – 7.004 kilometres. Race distance – 44 laps = 308.052 kilometres. 19 corners in total. Average speed 238km/h. Circuit based on public roads.
Aerodynamic setup – Medium downforce. Top speed 322km/h (with Drag Reduction System active on rear wing) – 312km/h without.
Full throttle – 70% of the lap (high). Total fuel needed for race distance – 144 kilos (high). Fuel consumption – 3.2kg per lap (high)
Time spent braking: 14% of lap. Number of brake zones – 6. Brake wear- Low.
Loss time for a Pit stop = 18 seconds (average)
Total time needed for pit stop: 21 seconds
Fuel effect (cost in lap time per 10kg of fuel carried): 0.38 seconds (high)
The Belgian Grand Prix is the eleventh round of the 2013 FIA F1 World Championship and comes after the teams’ enforced two week factory shutdown, during which no development or fabrication work may be carried out.
However many teams will have been planning a significant Spa upgrade in the weeks prior to the shutdown.
The Mercedes was the car to beat before the break and this race will be an important test of whether it has overcome its tyre management issues. Hungary indicated that it has, but the high loadings on the tyres at Spa will really show it. The Mercedes will be very fast in Sectors 1 and 3 on the lap, with the long straights and a couple of low speed corners, while the Red Bull is always fast on the middle sector, where downforce is key.
The Lotus is good everywhere and may well be able to benefit from its Double DRS device, to gain extra speed on the straights. However if it is not switching properly, the potential loss is greater than the gain. Last year Lotus struggled with tyre warm up on race day and was not able to challenge for the win.
It is a circuit on which Force India has always gone well.
As far as drivers’ form is concerned, Kimi Raikkonen has always been outstanding here, winning four times. Sebastian Vettel won in 2011 while Lewis Hamilton, Jenson Button and Felipe Massa have all won here. Fernando Alonso has never won at Spa.
Spa is notorious for fickle weather. With such a long lap, it can be raining on one part of the circuit and the rest can be dry. Also the temperatures can fluctuate dramatically, so it can be 25 degrees one day and 15 degrees the next. This can have a significant effect on the cars. The forecast for this weekend is for unusually warm and sunny weather, with temperatures around 22 degrees.
However this can change very quickly and it’s always a good idea to factor in a wet weather plan.
Likely tyre performance and other considerations
Pirelli tyre choice for Spa: Medium (while markings) and hard (orange markings). This is the first time this combination has been seen with the updated specification of tyres, post Silverstone.
In 2011 Pirelli brought the soft and medium tyre to Spa, last year they went to medium and hard and the result was a win for Jenson Button in the McLaren on a one-stop strategy.
Button was able to comfortably do the race with only one stop. His second stint, on the hard compound Pirelli tyre, was almost 170km. Sebastian Vettel finished second also on a one-stop strategy. They were helped by four early laps under the safety car after the start-line pile up triggered by Romain Grosjean, which took less out of the tyres than normal when they were heavy with fuel. This led a number of teams to switch strategy from a two to a one-stop, but not everyone pulled it off. If we see a safety car again this year, teams will clearly think of gambling along similar lines.
As Pirelli has now moved back to the 2012 tyre constructions, albeit with slightly softer compounds, the trend for the second half of the season is again towards fewer stops. This race will be something of an acid test, given Spa’s high loadings on the tyres.
The medium tyre will be easier to warm up and will be the main qualifying tyre. The hard will be more difficult to warm up, but is more durable. Last year, after the opening stint on mediums, most teams defaulted to longer stints on the hard tyre for the rest of the race. One of the key things for teams to establish in Friday practice is whether there is a faster way than this.
Two years ago, Pirelli had problems with blistering on some cars, most notably the Red Bulls, when they ran extreme camber angles. This led to very early first pit stops in the race, which dictated strategy.
Last year’s work on blister resistance helped to avoid a repeat of the problem and after Silverstone this year, Pirelli has successfully brokered with the FIA the right to dictate how its tyres are used by teams to a certain extent.
Number and likely timing of pit stops
The time needed for a stop at Spa is average at around 21 seconds. Although it’s a long pit lane, with a slow exit, the cars staying on the track must navigate a slow hairpin so the lost time isn’t as great as it might be.
Based on the tyre considerations listed above, the majority will probably go for two stops, around laps 13 and 28, but there is a possibility of a one stop strategy, pitting around lap 20. A safety car could push teams to switch from two stops to one.
Chance of a safety car
The chance of a safety car at Spa is statistically very high at 80% and 1.4 per race. Rain is one reason, but also accidents tend to be high speed and so there can be quite a lot of debris. Last year’s race saw a safety car after the pile up at the start triggered by Romain Grosjean, for which he received a one race ban.
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. Much can change.
As far as 2013 start performance is concerned drivers have gained (+) or lost (-) places off the start line this season on aggregate as follows:
+17 Van der Garde*****
+14 Di Resta
-17 Vergne ****
*Webber dropped from second to seventh after a clutch problem in Australia ** Hulkenberg did not start in Australia *** Sutil suffered puncture from contact with Massa in Bahrain ****Vergne retired following collision. *****Van der Garde and Maldonado made contact in Monaco. ******Bianchi started from pit lane in Monaco after stalling
Pit Stop League Table
Of course good strategy planning also requires good pit stop execution by the mechanics and we have seen tyre stops carried out in just over two seconds by F1 teams.
It is clear that the field has significantly closed up in pit stops.
The league table below shows the order of the pit crews based on their fastest time in the Hungarian Grand Prix, from the car entering the pit lane to leaving it.
1. Red Bull 21.343s
2. Mercedes 21.454s
3. Ferrari 21.597s
4. Lotus 21.643s
5. Williams 21.880s
6. Toro Rosso 21.996s
7. McLaren 22.107s
8. Marussia 22.159s
9. Sauber 22.303s
10. Caterham 22.384s
11. Force India 22.723s
The UBS Race Strategy Briefing is written by James Allen with input and data from several F1 team strategists and from Pirelli