How Rosberg came through, Ricciardo was compromised and Alonso got away with it

                            

The UBS Chinese Grand Prix was not as thrilling as the Bahrain GP, which preceded it, but from a strategy point of view and in terms of revealing the decision-making process that goes on behind the scenes during Formula 1 races, it was a fascinating event.
There were a number of talking points, one of the main ones being the Red Bull team trying to manage its two drivers, asking Sebastian Vettel to move over so as not to prevent team mate Daniel Ricciardo challenging Ferrari. Vettel initially refused, then relented. There was some confusion about what strategy each driver was doing. So did it cost Ricciardo a podium?
Another was the relative performances of Mercedes drivers Lewis Hamilton and Nico Rosberg; multiple factors worked against Rosberg in the race, but he still came through to second place through determined driving and clever strategy moves by Mercedes.

Pre-race Expectations
The temperatures in Shanghai (18 degrees on race day) were among the lowest we’ve seen recently and Free practice on Friday had shown that this – and the nature of the corner layout in Shanghai with two 270 degree right hand corners – meant that front left tyre graining was a limiting factor for most runners. This would re-appear as a major factor in the race.

The UBS Chinese Grand Prix was not as thrilling as the Bahrain GP, which preceded it, but from a strategy point of view and in terms of revealing the decision-making process that goes on behind the scenes during Formula 1 races, it was a fascinating event.
There were a number of talking points, one of the main ones being the Red Bull team trying to manage its two drivers, asking Sebastian Vettel to move over so as not to prevent team mate Daniel Ricciardo challenging Ferrari. Vettel initially refused, then relented. There was some confusion about what strategy each driver was doing. So did it cost Ricciardo a podium?
Another was the relative performances of Mercedes drivers Lewis Hamilton and Nico Rosberg; multiple factors worked against Rosberg in the race, but he still came through to second place through determined driving and clever strategy moves by Mercedes.

The Pirelli choice of soft and medium tyres was the right one for the event, with the medium not suffering too much from warm up issues while looking like a good consistent race tyre, judging from the Friday long runs. It was fast and consistent enough to mean that teams would likely favour it as the race tyre. The soft was faster for a few laps, but by eight laps into a stint, the medium was quicker. This decided most teams by around lap 25 at the latest that two stops was the way to go.
In terms of the choice between two or three stops, pre-race models showed the two stop to be quicker than the three by about 5 to 6 seconds, but one needed to handle the tyres very carefully if two stopping. The general trend this season compared to last has been one less stop; so whereas the soft tyre was good for only six or seven laps at the start last year in a three stop strategy, this year the majority of the leading runners went for two stops in the end.
The length of the first stint would be crucial as would the performance on the medium tyre in the second stint.
With a wet qualifying, everyone had new sets of slick tyres for each stint.

Red Bull strategy call: Did Vettel cost Ricciardo a podium?
There has been a lot of talk about the incident in the second stint of the race when Red Bull asked world champion Sebastian Vettel to let his young team mate Daniel Ricciardo through and he initially refused.
Ricciardo had outperformed Vettel in qualifying, grabbing a second place grid slot, with Vettel third.
On the grid however, in front of Ricciardo’s slot, there was some oil from a support race, which had been dealt with by marshals with some cement dust. This played a part in him getting a poor getaway at the start and falling behind Alonso and Vettel.
However he was able to run a longer first stint than Vettel, who suffered more front graining. The German stopped on lap 12, the Australian on Lap 15.
This is a tactic called “offsetting” and as we will see later it was also used to great effect by Mercedes on Rosberg’s race in China. The idea is to run longer than the car you are racing, accepting that you will not gain track position at that point and will lose some time initially, but you will gain later by having fresher tyres for an attack.
Riccardo was primed by the offset to get ahead of Vettel in the middle stint and challenge Alonso for the podium. Alonso had stopped on lap 11 and Ricciardo stayed out until lap 15, so he had a four lap offset and slightly more pace in his car, so he was in a position to fight Alonso. This would play out for him in the final stint of the race.
However the problem was that he had fallen behind Vettel with the poor start so the team had to decide whether to ask Vettel, who was slower and struggling with tyre graining, to let him through or to let the pair race.
Red Bull’s instinct was to ask Vettel to let him through. This was the right instinct for a maximum team result. If you are going to do this you have to do it immediately. Vettel refused initially and Ricciardo say behind him for several laps, losing vital laps and three seconds to Alonso in the process.

Red Bull says that it was considering moving Vettel to three stops at this point, but this is unlikely for a number of reasons; doing that would have forced Vettel to pass a lot of cars and thus significantly increased the risk of an accident.
And it would have dropped him into the Hulkenberg/Bottas battle, which he would have struggled to get past as the pair had the extra Mercedes power and were involved in their own scrap.
If three stops was a serious consideration he would have taken the soft tyre at the first stop – instead of the medium – and run a 14/15 lap stint on it.
By lap 24/25 everyone had decided that two stops was the way to go and so when Vettel’s engineer told him to “stay out, it helps us” this indicated that they had committed to leaving him on a two stop. He was never on a different strategy to Ricciardo.
By this point Ricciardo was already past Vettel, although he said afterwards that he couldn’t tell if he was being let through or not.
If Vettel had fully intended to let him through, firstly Ricciardo would have known about it and secondly neither of them would have needed to go onto the tyre marbles in the move.
Alonso was a little compromised by Mercedes’ strategy with Rosberg, as we will see, but was still able to be very clever in the way he managed the gap to Ricciardo in the final stint and he eased off on the last lap, so the gap appeared smaller than it was.
Several leading F1 strategists think that if Vettel had yielded immediately Ricciardo would have caught the Ferrari with around 4 laps to go, but agree that passing him would have been difficult.
We were denied a thrilling battle at the end, but Red Bull were in a difficult situation, for the possible gain of Ricciardo having a chance of challenging Alonso for a podium. On one hand it was worth it, because that would have been a better team result than they did achieve, but on the other hand it wasn’t a certainty and it resulted in a negative impression over the Vettel team orders situation.
It will be interesting to see what they learn from this and how they manage it in future races, should the situation arise again.
But the fact that they followed the correct initial instinct – to get Ricciardo ahead of Vettel – showing that Vettel does not necessarily enjoy any superior status.

Rosberg beats the odds to finish second
Nico Rosberg’s second place did not receive much coverage, as all the attention was on Hamilton’s 25th win and the Red Bull team orders story, but it was impressive how he came through the field despite quite a few setbacks and a poor start.
His car had no telemetry, which meant that the team had to ask him to monitor fuel use and they had no idea of how much damage his car sustained in contact with Bottas at the start nor about his Energy Recovery and storage situation, which is a vital part of strategy these days.
Rosberg started fourth and was sixth at the end of the first lap, but his real challenge was to pass the two Red Bulls and Alonso. He picked off Ricciardo through strategy. He pitted on lap 13, moving to the medium tyre, which told Red Bull that he was two stopping and challenged them to cover him. Ricciardo didn’t, which shows that Red Bull was looking at the offset to Alonso and didn’t think they could race Rosberg.
This took the German past Ricciardo when the Australian stopped.
With Alonso Mercedes’ strategy was the opposite – they went for an offset, but first dummied Ferrari by sending mechanics out on lap 33, as if they were about to stop. As Alonso was ahead on the road, his team brought him into the pits, but Rosberg continued. He built a four lap offset and then had much newer tyres to pass the Ferrari in the final stint.
This pushed Alonso into a 23 lap final stint, which was longer than ideal in his battle with Ricciardo, but circumstances explained above show that he was able to get away with it and score Ferrari’s first podium of 2014.

From: http://www.jamesallenonf1.com