Red
Bull had the fastest car on track in China but in a thrilling race McLaren
out-performed them on strategy - so where and why did it suddenly all go wrong
for the world champions?
Vettel
was dominant in qualifying, some 0.715 seconds faster than the lead McLaren,
and his advantage was similar to what it had been at the opening race of the
season in Australia.
In
the season opening race, however, Vettel and second-placed Hamilton both chose
the same soft/soft/hard tyre strategy and Vettel won easily. In China, the
drama unfolded when the lead pair did not match each other in race strategy -
but it was not quite as clear-cut as it may have appeared.
Tyre performance is very specific
to track, temperature, car and driver style, so each race sees different tyre
wear on different tyres. With no data to look back on and analyse, the teams
are riding blind at every race this year.
McLaren
had chosen a soft/soft/hard strategy at the start of the Chinese race but
changed to their race-winning soft/soft/soft/hard approach after analysing
their pace - and most importantly that of the competition - in the opening
stint.
Looking
at the list of pit stop strategies for the top 10 finishers (shown below) it is
clear that Mercedes were the only team to have planned the soft/soft/soft/hard
strategy from the outset, as they had a much shorter stint on their first set
of softs.
Rosberg
stopped on lap 12 while Vettel, the McLarens and the Ferraris all stopped
between laps 14-16 - and it was at this point when it became clear the
three-stop strategy would be fastest.
Over
the laps from 11 to 17, which covers all the leaders' first stops, Rosberg ran
in the mid-1:45s on old softs for one lap before a pitstop (which importantly
has a relatively quick in-out lap) then had four laps running on fresh softs in
the low-1:43s.
In
contrast, Hamilton
continued to post times around 1:45s on old softs and did a 1:47.7s lap when
his tyres started to go off badly before his pitstop.
By
lap 17, Rosberg was in the lead having taken a total of 12:27.549s to complete
those seven laps, while Vettel (who had two more laps on old softs) took almost
10 seconds longer and Hamilton
(with three laps longer on old softs) took 13 seconds longer than Rosberg.
Not
only that, but Webber, running a completely different strategy to make his way
up from 18th on the grid in the other Red Bull, had chosen hard tyres for the
start and only managed to go 10 laps on them before they started going off.
McLaren
predicted that if Vettel stuck with a soft/soft/hard strategy, not only would
he have to eek out his soft sets but he would struggle by the end on the harder
compound too. So they took the decision to switch strategy and made the call to
bring Hamilton
in early on his second set of tyres, on the same lap as Rosberg.
At
that point, Rosberg was in the lead with Vettel was three seconds but 4.3s up
on Hamilton, with Massa between them on a two-stop strategy.
If
Red Bull had followed McLaren and pitted Vettel a lap later to cover their
move, the three would have probably stayed in the same positions - and Mercedes
could even have been in the mix for victory.
However,
even without the fuel problems Rosberg suffered, Vettel's better pace would
almost certainly have enabled him to overhaul the Mercedes driver - and the
result would have been very different story...
The
problem for Red Bull, then, was not the fact the two-stop strategy failed, but
the fact they did not recognise it wouldn't work and, in the head of the
action, failed to adapt.
China top 10 finishers pit stop strategies (number in
brackets is amount of time the tyres lasted)
1. Hamilton (3): S
(15) S (10) S (13) H (18)
2. Vettel (2): S
(14) S (17) H (25)
3. Webber (3) H
(10) S (15) S (15) S (16)
4. Button (3): S
(14) S (10) S (13) H (19)
5. Rosberg (3): S
(12) S (13) S (14) H (17)
6. Massa (2): S
(15) S (18) H (23)
7. Alonso (2): S
(16) S (16) H (24)
8. Schumacher (3): S
(10) S (16) S (13) H (17)
9. Petrov (2): S
(17) S (20) H (19)
10. Kobayashi (2): S
(14) S (16) H (26)