Articolo di @spontonc e di @smilextech – Traduzione di Alessandra Migale (@ Aycienta_44)
Bottas overcame the challenge: after four Grand Prix with Mercedes he won
the Russian GP. Why was it a hard task? Because last Sunday the W08, even
if it has improved since Bahrain, has been inferior to the excellent Ferrari
SF70H.
RUSSIAN GP: a not so aggressive
Vettel and the waking effect favored the excellent start of Bottas
The men of Mercedes already knew after Friday’s long run tests that the only
possibility to beat the reds was to pass them in turn 2 (at least with one of
the two cars). On the circuit of Sochi the start has always been crucial as
the overtaking chances are minimal. A quite boring race, with no overtakings
and with no one inside the top teams that opted for a two-stop strategy. Too
constant was the UltraSoft compound on a smooth and unattractive track like the
Russian one. Hulkenberg ran over 2/3 of the race with the softest compound.
We do not like it; it is true that drivers can now push for longer races, but
why at this point not changing everything, by eliminating the annoying rule of
the two compulsory compounds, giving to teams the opportunity to choose the tyres
to use at every race?
Coming back to the race analysis, the long straight that leads to
turn 2 has been for sure an advantage for those who started from behind,
mainly Bottas who was starting from the clean side of the track. He in fact exploited,
after the restart caused by the unreliability of the Mclaren-Honda of
Alonso, the excellent starting system of Mercedes, factor that last
year caused many problems to the German team. We have also to consider the
superiority of the Power Unit Mercedes in the first meters (ensured by the so
called “magic button”), and the lower drag of the W08 which allows
to have higher top speeds than the SF70H.
There are also other things to point out about the start of the Grand
Prix: the wake that the
cars could have exploited and the imperfect getaway of Vettel. In our opinion the
German driver of Ferrari has made two mistakes: an anticipated shift gear and a too
conservative approach when Bottas went side-by-side to overtake him. If Vettel had been more aggressive, only by slightly squeezing
the Mercedes’ driver to the left, Bottas should have for
sure slow down, perhaps losing also the position on Raikkonen who arrived in
turn 2 not so far from his teammate by exploiting the wake effect. So, the wake effect: on a main straight like the one of Sochi this effect allows drivers behind to gain
more or less two cars and a half. This factor has therefore played in favor of Bottas.
If, as said above, Vettel had been less conservative he would definitely have
won his third GP of the season. If in Bahrain a substantial part
of the final win has been constructed upon the good start of the Ferrari’s
driver (aggressive overtake on Hamilton in turn 1), in Russia things went not
so well. This is racing.
For those who do not read regularly our website, we remind that Ferrari introduced during the weekend
a wing with less downforce than those already used, coupled with a double
monkey seat. They also decided to install a new turbocharger in
order to solve some problems of reliability that occurred during the winter
tests and the first races of the season. The men who work everyday in Ferrari know it: with a substantial
step forward in the aerodynamic efficiency, the championship would be within
reach. The SF70H still pays too
much drag with respect to Mercedes. This can have important consequences on the Power
Unit (a more aggressive use of it can cause some reliability problems). The new car of the
Italian team generates the greatest extent of downforce from the wings, paying
this choice with an increase in drag, while Mercedes is able to generate downforce from
the body of the car, paying less in terms of drag. It is not thus the
Power Unit, mainly during the
race, that is
responsible of the difference in pure speed between the SF70H and the W08. By using extreme
setups, Ferrari is however able to
reach good top speeds on the straights thanks
also to a flexible bottom. These values are however still inferior to those of
the W08 that, to the same
extent, is able to adopt a neutral setup on the straights thanks only to a soft adjustment on the suspensions, given a less emphasized
rake.
RUSSIAN GP: the
analysis of the first stint
The first stint of
the race is the one which actually decided the race after a so-so start
for the two Ferraris. And in this 1st stint some factors played a crucial role. First of all, a Mercedes that worked very much on Friday in
trying to set the first part of the race, the less favorable
for the W08 in the first races
of this season. Mercedes that with a high
quantity of fuel has always struggled on the rear tyres. These problems, caused by an
incorrect warm up of the soft compounds unlike the hard ones, were accentuated
by a setup that was chosen to make the tyres work better on short stints (for
instance, the Quali) and that distributed more weight on the front rather than
on the rear. This problem was solved before the weekend in Sochi (weight moved
on the rear), and in fact penalized
the W08 in Quali but bore
fruits in the first part of the race. First stint in which Bottas made the difference also
thanks to some defects on both the SF70H. Defects that concerned the correct
cooling of the Power Unit. During the first
twenty laps, both drivers has been forced to drive with a weakened engine to
avoid serious issues. This fact allowed Bottas to gain much time in the first
sector and to reduce the gap accused over the weekend in the S2 and S3.
Analyzing the graph below, Bottas has been constantly quicker than the SF70H until
lap 20. After having
solved the problems of overheating, mainly caused by the fact that both Ferraris
were close to other cars, Vettel has been able to increase his speed and reduce
the gap from the leader. In this phase of the race, both Ferrari and
Mercedes suffered of blistering on the left-front tyre. This problem occurs when a part of the tyre overheats abnormally and
generates small bubbles inside it. This consequently produces some detachments
that can have different areas according to the level of heating and mechanical
stress at which they are subjected. The bubbles become then real holes that
can turn out to be very
deep. According to Pirelli this problem was due mainly to the long
turn 3.
But Ferrari, especially Vettel, has not been so much
affected by this problem while Bottas, lap after lap,worsened his times. Even by analyzing
the tendency line we see how the one of Bottas at a certain point suddenly rises
while the one of Vettel tends even to decrease, thanks also to the fact that
the German driver did not manage to exploit the UltraSofts properly during the
first laps.
Looking at the
pace of the 4 top drivers, we can see that Vettel and Bottas had a quite
similar rhythm. Raikkonen was 2 tenths
slower. 4 tenths slower
Hamilton who, in this first
stint, had some problems
of overheating to the
Power Unit, such those of Vettel and Raikkonen. The electronics of
the Power Unit
Mercedes cut the cylinders according to the temperature
detected by the sensors, lowering so power and torque. In addition to this the English driver
during Quali damaged the flat bottom of his car on a curb, worsening
so his performance.
RUSSIAN GP: why
did Ferrari choose to avoid the undercut on Valtteri Bottas?
The answer is in our opinion pretty simple: Ferrari never had a real chance of doing an
undercut on Bottas. The gap has always
been greater than 2 seconds (that is the gap needed to anticipate the pit stop).
Mercedes, having for this
reason the gap to protect the position, anticipated the pit stop of Ferrari also because the Finnish driver
should have overtaken some lapped drivers within few laps. This fact could have
damaged Bottas, making him slow down and favoring the Ferrari of Sebastian
Vettel and his undercut. Perfect the strategy of Mercedes but perfect at the
same time the strategy of Ferrari, that opted for leaving Vettel on track for
more laps seeing that the performance of the UltraSofts was not getting worse and
mainly seeing that Bottas was struggling on SuperSofts.
RUSSIAN GP: the
analysis of the 2nd stint
In the 2nd part of the race, on SuperSofts, the
two SF70H were the fastest on track. Vettel gained the advantage of having newer
tyres than the other drivers, thanks to a longer 1st stint (only Hulkenberg ran for more than 40 laps on UltraSofts).
Raikkonen was faster than Bottas of almost 1 tenth while Hamilton, on these tyres, suffered more than during the 1st
stint. Bottas, even if slower
than Vettel, has been able to
manage in the best way possible the advantage making only one error: the lockup
in turn 13. Notwithstanding
this, he held off a Sebastian Vettel who
has never managed to put pressure on him finishing the race at 6 tenths. A Mercedes that seemed to
struggle a bit more on SuperSofts that is the only compound which has
been substantially modified from last season. The reason why Mercedes had some difficulties
on these tyres is to be found in the cooler track temperature, a negative
factor for the German team with the chosen setup and in the fact that this compound needs few degrees more than
the UltraSoft to work properly. In addition to this, Bottas and Hamilton
had troubles in keeping at a steady temperature the rear of their cars because of the low
quantity of fuel at that point of the race. Due to relevant changes in the
setup and to the different characteristics of the tarmac of the track, the
conditions in which Mercedes went faster than Ferrari totally reversed. This gives us an
idea of the bulk of work that the technicians of the German team have to do to find the correct balance between
the two situations and giving to the W08 the possibility to express its full
potential. And the update that will be brought at the Spanish GP goes in this
direction: trying to make the W08 a car whose balance is simple to find.
RUSSIAN GP: positive
or negative race for Ferrari?
The overall picture could be seen from different perspectives. Positive because
Vettel increased his advantage on Hamilton in the drivers’ standing. Negative because, after the
front-row lockout of Saturday, all the fans
expected a win. If Vettel had been
more aggressive and a little bit quicker in the shift gear at the start, the
win would have been much more easier given that the cooling problems of the car
probably would have not occurred.
