Formula 1 Preview–Passing Highlight from MERCEDES GP PETRONAS

Race Preview Feature Five: Making the impossible, possible

With the exception of Monaco, which is an anomaly in every way, the
Circuit de Catalunya has long been the circuit at which overtaking is
more difficult than anywhere else in Formula One. 16 of the 20 races
held at the circuit have been won from pole position, including every
one in the past decade. In the past three years, normal overtaking
manoeuvres have been measured in single figures; on average, there have
been 2.3 ‘normal’ passes for position per Spanish Grand Prix since 2008.
So if a circuit is going to provide a yardstick for the success of the
2011 regulations, which have so far seen an average of 24.5 ‘normal’
overtaking moves per race, and many more with the use of DRS, then
Barcelona is it…

Why has overtaking historically been so difficult in Barcelona?

The fundamental impediment to overtaking at the Circuit de Catalunya is
that the 880m main straight is preceded by the fast Turn 16. It is a
corner through which it is hard to follow another car closely and, when
performance differentials between are small, this makes overtaking
extremely difficult. Furthermore, teams have normally been testing at
Barcelona and have optimised the car and tyre usage, which usually gives
less variation in performance and strategy than normal.

Can you quantify the impact of running in another car’s wake?

Yes. Downforce levels are monitored by the car’s on-board sensors and
the closer you get to the car in front, the bigger the loss in
downforce. This loss occurs across the whole car, but is more pronounced
at the front, hence the tendency for the following car to understeer.
The loss begins to occur when the gap between the cars is 3.5s. When one
second behind, the chasing car loses approximately 7% of total
downforce; when 0.5s behind, this rises to around 12%.

How is overtaking measured?

The traditional method of counting on-track overtaking relies on
registering position changes from a lap chart; however, this method
cannot take account of multiple passes on a single lap, or passes made
on in- and out-laps. The team calculates the number of overtaking
manoeuvres using a combination of video, timing data and GPS technology.
This method enables the ‘value’ of overtaking moves to be categorised
for use in strategic calculations: for example, passes between
team-mates are categorised separately because one driver can choose to
let the other pass, although this is not automatically the case;
similarly, passes by faster cars on those from the bottom three teams
are categorised separately as their strategic importance is different.
However, there is no standard definition of a ‘real’ overtaking move, so
differing conclusions can be reached according to the method used.
Consistency of method is as important as overall accuracy.

How much overtaking occurred in Barcelona over the past three years?
The raw statistics are as follows: 2008, 11 moves; 2009, three moves;
2010, 10 moves. However, the total from 2008 includes passes made
because of damage or mistakes, while the 2010 number includes passes by
faster cars on a car from the bottom three teams. The number of ‘normal’
overtaking manoeuvres was: 2008, two; 2009, three; 2010, two.

The picture has changed dramatically in 2011. How so?
The number of overtaking moves has not only increased significantly
compared to 2010, but it has also risen steadily with each race so far
in 2011, from 30 total moves in Melbourne (including all types of pass)
to 112 in Turkey. Within these totals, the number of ‘normal’ passes
between cars from different teams more than doubled between Melbourne
and Sepang, and has since then remained reasonably consistent: the race
in Turkey saw 31, for example, compared to 12 in Melbourne and 29 in
Sepang. In contrast, the number of DRS-assisted passes has risen
significantly, from five in Melbourne to 40 in Turkey. In percentage
terms, DRS played a role in 17% of passes in Melbourne, compared to 36%
in Istanbul; conversely, ‘normal’ on-track passes accounted for 40% of
passing in Melbourne, and 28% in Turkey.

How much passing has occurred overall so far this year?
The raw totals are as follows: Australia, 30; Malaysia, 70; China, 90;
Turkey, 112. Within these totals, the sum of ‘normal’ and DRS-assisted
moves is: Australia, 17; Malaysia, 48; China, 53; Turkey, 71. Comparing
the raw totals from the 2010 Spanish Grand Prix and the 2011 Turkish
Grand Prix, one can see that the race in Istanbul featured over eleven
times more overtaking than last year’s race in Spain: 112 moves compared
to ten.