Williams ready for demanding weekend at Sepang
Only one week after the Australian Grand Prix, the Formula One circus travels to the Sepang International Circuit for the Malaysian Grand Prix. The biggest worry for the Williams F1 drivers at Sepang is the heat, high humidity and later start time of the race.
Sepang in a nuthshell
At many Grands Prix, drivers who qualify towards the front favour two-stop strategies – a lighter fuel load equates to speed, rather than stealth – while some farther back gamble on a single pit stop, in the hope that circumstance might shuffle them into the reckoning. In the gruelling heat of Malaysia, significant tyre wear might dissuade anybody from taking such a gamble. The track often remains slippery, too, because fierce overnight storms wash away rubber laid down the previous day. Note that this year’s race is scheduled for late afternoon, when tropical rain is a possibility…
Talking Technical
Car dynamics
Average turn angle indicates the average angle of a circuit’s corners expressed in degrees. The higher the average turn angle, the more acute corners in the circuit configuration and hence the greater propensity for understeer to compromise lap time. At Sepang, the average turn angle is 1390, against a season average of 1100, ranking as the circuit with the highest average turn angle across the Championship. As a consequence of the circuit’s physical layout, an understeering car balance will have a high punitive effect on lap time.
The end of straight (EOS) speed at Sepang was 301kp/h in 2008. Sepang ranks as the 12th fastest EOS speed in the 2009 calendar, and this is one indicator of the wing level typically selected to optimise the downforce/drag ratio.
Pitlane & refuelling strategy
The pitlane length and profile (i.e. corners in the pitlane entry) contribute to the determination of the optimum fuel strategy. The pitlane loss at Sepang is approximately 22 seconds, the 5th most penalising pitlane in the Championship. To complete a normalised distance of 5km around the Sepang circuit requires 2.38kg of fuel against an average of 2.42kg per 5km across all circuits this season, making the circuit the 5th least demanding track of the year in terms of fuel consumption.
Safety car
Another key contributor to the determination of race strategy is the likelihood of safety car deployments, which are influenced by weather considerations, the availability of clear run-off areas that allow racing to continue while recovery takes place and the circuit profile, especially the character of the entry and exit into turn one at the start of the race. Since 2002, there have been no safety car deployments in Sepang, making it statistically unlikely that the circuit character, based on historic data, will induce safety car periods.
Temperature, pressure & humidity
It is a long observed tradition that drivers arriving at Interlagos complain about a lack of grip and an absence of engine power. Having become acquainted with a baseline of engine and aerodynamic performance during the season, the climb to 750 metres above sea level for one of the final races can, courtesy of the reduction in air density, rob a Formula One car of engine power, aerodynamic performance and cooling. The losses can come close to double digit percentages and thus have a very real impact on car performance. Air density is a factor of the prevailing ambient temperature, which varies most significantly by season, air pressure which is closely linked to altitude and, to a much smaller degree, by humidity. Thus if races are run at the same time each year, the factor that tends to have the greatest bearing on air density is elevation. Sepang is 40m above sea level and has an average pressure (1004.41 mbar) when compared to other races venue in the 2009 Championship. As a consequence, the circuit’s ambient characteristics will be average for engine performance across all tracks visited during the season.
What the Drivers Say
On Sepang circuit
Kazuki Nakajima: “For me, Sepang is one of the most exciting tracks we visit during the year. That doesn’t mean it is an easy track, far from it, as it has some complex and technical corner sequences and some that demand special attention such as turns 11 and 14 where your braking and turn-in sequence is different to say the least.”
Nico Rosberg: “Just like Kazuki, I really like the Sepang circuit, it is fast and flowing and has a nice variation of corners that makes it really exciting to drive.”
On Malaysia (the climate, the people, the food..)
Kazuki: “Well, Malaysia is closer to my home country than many of the places we visit, so I find it more familiar in terms of the culture, the food etc. I raced at Sepang in Japanese GT, so I am also a bit better acquainted with the place, but of course the heat and the humidity are quite exceptional.”
Nico: “The climate makes the racing very demanding for driver and machine. The heat and humidity means that it is physically exhausting and this is one track where the fitness training over the winter really pays off. I love the country, there is a nice warmth about the people too and like almost everywhere in Asia, I like the food, so it is a good place to visit every year.”
Standing back from Albert Park – Reflections of the first race
Nico: “Of course we would have liked to have achieved more in Melbourne, but three solid points was a good start. More encouraging was our pace as we were right there with the quickest, which makes me hopeful for a good season.”
Kazuki: “I was running as high as P4 and this would have improved to P3 when Rubens pitted, so I can’t deny the sense of disappointment in how the race turned out, but I have shut this out of my mind already and I am only taking the positives of the potential we showed with me to Malaysia.”
On the late start times for the first two races
Kazuki: “It was difficult with the low sunlight in Australia, especially as the light flickered and changed under the tree cover. We won’t have this type of shadow at Sepang, but there is a different issue which is the possibility of reduced light conditions mixed with the likelihood of rain, so for sure these late race start times will have a bearing on my approach to qualifying and the race.”
Nico: “In Melbourne I found this a big concern as towards the end of the race the visibility was very poor, which increased the danger in my view as it was more likely that you could make a mistake. I’d rather the race changed back to its original start time or became a proper night race - that would improve matters a lot. ”
Source Williams
