What did we learn from pre-season testing?

Having completed eight days of testing at Barcelona, the Formula One field has rounded off its on-track preparation for the 2019 World Champiopnship. F1Technical.net’s Balázs Szabó takes a look behind the number to find out what the pecking order could look like when the season kicks off in Melbourne, Australia in a fortnight’s time.

Following the first week of testing, Ferrari presented itself in an extremely strong shape. One could not ignore the pace and reliability of the Italians’ SF90. However, the second week brought a change: Ferrari was dogged by reliability problems while Mercedes seemed to find the harmony with its W10. Still, Mercedes clings to its hypothesis, claiming that Ferrari has a healthy lead out at the front.

"I think it's potentially half a second. Something like that, potentially,” said Lewis Hamilton on the last day of testing. His team-mate Valtteri Bottas said that Mercedes needs to raise its game if it wants to pose a real challenge to Ferrari. „We need to keep pushing and find more performance if we want to be competitive in Melbourne,” he said.

Following Mercedes’ claims, Ferrari’s new team principal Mattia Binotto tried to dismiss this illusion on Friday, noting that it was „completely wrong’ to believe that Ferrari was leading the entire F1 field ahead of the season opener.

"These days are very important in the preparation of the entire season. I'm happy to know that Hamilton believes we are faster. I believe they are very strong, I believe Mercedes will be very, very strong in Australia. It would be completely wrong to think today that we're faster than them. Here, we may run different fuel levels, we've got different programmes,” Binotto is quoted as saying by motorsport.com.

On the first day of the second week of testing, Mercedes’s development package left its rivals shocked and breathless. The Anglo-German team reworked almost every piece of the launch version of the W10 for the second test session. The team disclosed that this was always going to be the plan. The basic package which broke cover before the winter test and which completed the shakedown session was finalized at the end of November. The outfit wanted to make sure that they could pop up with a reliable package without any delays at the first test. After finalizing this ‘back-up’ package, the team then could start working on an aggressive design.

The new package included a modified nosecone, front wing, floor, bargeboards, engine cover and a new T-wing.

Even if Mercedes kept its elegantly-shaped nose, the new nosecone features a tapered-in section, feeding more air to the huge vanes located beneath the nose. These vanes channel the air towards the floor. As these vanes feed an increased amount of airflow towards the back of the car, the floor also had to go through changes. It now has more sophisticated slots which try to seal floor. These sealing skirts maintain the negative pressure under the floor which effectively pulls the car down to the asphalt.

The team modified its front wing, as well. The basic philosophy remained – the flaps show an even depth across their span in contrast to Ferrari. However, the endplates went through some significant changes. Previously, they turned slightly inboard, now they are directed slightly outboard. With this solution, Mercedes follows Ferrari’s path and generally the trend of recent years, the outboard-directed endplates try to turn the airflow around the front tyres in order to decrease drag.

The W10’s engine cover also went through a redesign. The section behind the air intakes inside the sidepods drop more pronouncedly downwards, channelling the airflow more aggressively towards the back of the car. The tighter engine cover also meant that the team had to work on the cooling system of the car to keep the necessary cooling level with the aggressively reshaped sidepods.

While midfield teams, especially McLaren and Toro Rosso were constantly carrying out qualifying simulations with little fuel on board and fresh softer Pirelli tyres, top teams rigorously avoided showing their real pace. However, on the seventh day of testing, Ferrari resigned itself to simulating qualifying circumstances.

On his final day of testing, Leclerc spent an hour with completing short runs on low fuel loads. The Monegasque’ best time of 1m16.231 was registered on the softest C5 compound. On Thursday, Mercedes was diligently working on longer runs, but on Friday, the dominant team of the past five years gave fresh C5 sets to both its drivers. In the morning, Valtteri Bottas recorded his best time of 1m16.561 on C5 at 11:41. To give an answer for Mercedes’ time attack, Ferrari sent Sebastian Vettel out on the same compound at 12:34. The German’s best lap time of 1m16.221 proved to be the best of the entire pre-season testing. Lewis Hamilton completed his qualifying runs in the afternoon. The Briton recorded his best of 1m16.224 on C5 at 17:06. A few minutes later, he came out to the track on the shiny C5 once again, but he could not be faster than 1:16.367.

In terms of sector times, Ferrari had the upper hand in the first and second track section. The Italians’ best first sector time was 0.082 quicker than Mercedes’ while the difference was 0.174 in the middle part of the circuit. In the last segment, Mercedes was 0.202 faster than Ferrari. These sector times are in harmony with the on-track behaviour of the SF90 and W10. The Ferrari contender was able to carry incredible stability through the fast bends while the W10 raised eyebrows with how stable it was in the chicane and out of it.

The qualifying simulations indicate that Ferrari and Mercedes are neck on neck – at least on the Barcelona-Catalunya circuit in this state of development. However, some signs suggest that Ferrari might have a little edge over its rival at the moment. Both Bottas and Hamilton completed their qualifying simulation on lower ambient and track temperatures which could help the engine to produce more energy from the same amount of fuel due to the higher oxygen content. It also could help the for the Barcelona track too soft C5 compound as it is prone to overheating as driver arrive to the slowish corners of the last sector. On top of that, Ferrari was not able to produce the same top speeds during its C5 runs as it did before, indicating that the Maranello-based team switched to a lower engine mode. Thirdly, Vettel’s time of 1:16.720 on the C3 and Leclerc's time of 1:17.2 on the C2 compounds were eye-catching results, to say the least.

Following the first day of the second test week when Mercedes carried out extensive aerodynamic measurements with its new upgraded package, the team put its focus on long-run performance as of Wednesday. Ferrari simulated an entire race weekend with Leclerc on Thursday and with Vettel on the final day.

Bottas and Leclerc both completed a race simulation on Thursday with the Monegasque having started his own simulation some 20 minutes later. Interestingly, Mercedes did not intend to complete a whole race simulation with Hamilton. It leaves us with Bottas and the two Ferrari-drivers to compare the Mercedes’ and Ferrari’s long-run pace. The comparison is further complicated by Vettel’s electrical problem which forced the German to park his SF90 on the race simulation after his second visit to the pit.

All three drivers opted for a two-stop strategy. Bottas used the compound pattern of C3-C2-C2 as did Vettel. Leclerc opted for the C2 compound for all his stints. During the first stint, Vettel was five tenths, Leclerc four tenths quicker than Bottas on average. Over the second stint, the two Ferrari drivers had an advantage of four tenths. Bottas and Leclerc were identical on average in their last stints. Interestingly, the Ferrari newcomer started his stint very strong, but his pace faded towards the end of his simulation while Bottas could maintain his performance in a consistent manner.

It is worth noting that Sebastian Vettel’s second stint was outstanding, but he was held up on three occasions. Disregarding these three laps, the German achieved an avarage of 1:21.9, two tenths quicker than his team-mate Leclerc and six tenth quicker than Bottas.

In fact, Mercedes’ hypothesis about Ferrari’s extremely high level of competitiveness was backed up with its own struggles during the first week of testing. After the first four days, the James-Allison-led technical group scratched its head because the W10 was behaving like a diva and its balance was too dependent on ambient and track temperatures. During longer runs, the front tyres developed blisters, leading to understeer towards the end of longer stints. However, the new upgrade package provided the drivers with a better feel for the front end of the car, the balance improved as well. The better graining-resistance enabled the driver to complete longer runs with much better consistency on heavy fuel loads. Mercedes could make inroads both with its single-pace and its long-run performance towards the end of the pre-season testing.

At Ferrari, Mattia Binotto and its technical staff first experienced headaches during the second week of testing. The SF90 developed a long list of technical issues on all four test days. The main pillars of the list included technical glitches with the electronics system, the exhaust, the wheel rim and the cooling system, all of them leading to the loss of valuable track time
.
The longer stints, the qualifying simulation and the fact that the SF90 was competitive regardless the timing during the day indicated that Ferrari are a tiny bit ahead of its arch-rival Mercedes, however the technical problems of the second week were alarming for the Maranello-based team. As the saying goes: to finish first, you must first finish…