The teams reflect as the first day of the second pre-season test comes to an end with 1,146 laps completed.
After that came some relatively long runs, switching between the soft and medium compound tyres. It was on the latter that the German set his fastest time in 1:20.396, on his 66th lap.
"It was a good day's work," said Vettel. "We managed to get through our programme, even if the conditions weren't always ideal, because of the wind."
Mercedes kicked off its second week of testing with a productive day's work. In considerably improved weather conditions, the W09 ran for a total of 824 kilometres, with Valtteri and Lewis both completing similar mileages.
Valtteri ran through a series of fundamental set-up changes on the day, as the team worked to understand how the tyre compounds react to these changes. Lewis worked on a number of recovery strategies for potential sensor failures and tried out aerodynamic bodywork parts for the upcoming season.
"The conditions today were much better than last week and we're all really happy about that," admitted Bottas. "We got lots of valuable data today. This morning we focused on medium to long runs, trying different mechanical setups of the car.
"In these weather conditions we start to really work the tyres and we had a few issues to manage. So we had a few more challenges with the tyres than we had last week, but at least now they can warm up.
"We keep discovering more about the new car, learning how it reacts to different settings. We did more than 80 laps - so more than a race distance, a really good mileage. The car was very reliable, I really enjoyed being back in the car and I'm looking forward to continuing tomorrow.
"It's been a good day," added Lewis Hamilton. "We've got through everything we needed and put good mileage on the car - it's been productive.
"The biggest challenge we faced today was to get the tyres working properly on this new track surface. The medium tyre was difficult to get working; the soft tyre is better for warm-up, but suffered with degradation. But we are learning all the time.
"Overall it's been a good start to the second test although there is not a whole lot to say at this moment. We have not worked too much on fine-tuning the set-up as we're mostly still gathering information. In the next couple of days, once we get into the long-runs and some shorter qualifying-style runs, we will get a better idea of where the car is."
Max Verstappen kicked off REd Bull's final week of testing by powering through 130 laps on his way to the day's third best time. The Dutchman logged his lap of 1:20.649 midway through the morning on the medium compound tyre to finish just under three tenths of a second off top spot for the day.
His afternoon session was interrupted by a stoppage on track but the team was able to rectify the issue and Max returned to the circuit shortly before the chequered flag.
"It was a good day today," said Verstappen. "We did a lot of laps and that's really important, just to put mileage up on the car," said Max. "We had a small problem with the battery late in the day, so we had to change that and it takes a bit of time, but afterwards it was all good. The car feels good.
"Everyone of course wants to know where we think we are in relation to our opposition but honestly it's impossible to tell until we get to Australia, as you don't know what everyone else is doing. In terms of where this car is improved over last year, again it's very difficult to say as the new surface here changes how you drive and that, together with the new tyres, makes it difficult to pinpoint any particular area. Also, with the first week not being that successful in terms of temperatures and so on, it's still all to be discovered. I know it feels faster though!"
"We had a good start to week two," added Head of Race Engineering, Guillaume Rocquelin. "We got through 85 laps in the morning and everything was running very smoothly. We got a long way through the test programme then, so we were able to try out some things in the afternoon and we took the decision to do some shakedown tests and the result was small electrical problem.
"We lost an hour as we had to change the battery but it was a calculated risk and we learned something as a result. In all, I'm pretty happy with the amount we got through today. Even though we're not chasing it, the performance was decent too, so let's hope for more of the same when Daniel is in the car tomorrow."
"It was a really positive day overall from the performance side," said Pierre Gasly, "we had a small issue this afternoon with the brake system which took longer than expected to fix, so we didn't run as much as I would have liked - that's part of testing though! So far everything has run perfectly, the car was pretty nice and we made some improvements compared to last week, so we are headed in the right direction."
"We had a reasonably productive morning where we were able to do some running in more normal conditions compared to last week," added James Key. "Pierre was happier with the car, we have made a lot of setup changes from what we learned last week. The engineers have done well to pull the analysis together in the short time between tests and find some promising directions. We also did a bit of work on the aerodynamics side taking further measurements first thing then moved onto more chassis setup tests and initial investigation into tyre performance in the warmer conditions.
"Unfortunately, this afternoon we suffered a brake system issue on the chassis side which was difficult to trace and took a long time to address, needless to say it is important to ensure any issues with critical systems are dealt with correctly and as the afternoon went on time became increasingly short to get the car back on track. Sadly we missed some running this afternoon due to that problem, however we will work overnight to make sure that we are ready and set for tomorrow.
"We apologise to the drivers and Honda for missing a good opportunity of running this afternoon and getting through more the long test item list we still have, however we need to put that right for the rest of the test and make good use of the remaining three days."
"The first day of the second pre-season test got underway in Barcelona under blue Spanish skies and much warmer temperatures than we experienced last week," added Toyoharu Tanabe, Honda's F1 Technical Director. "It means that conditions on track were much closer to those we will experience at the races.
"Last week we concentrated on data acquisition and systems checks and, from today, our programme is more race focused.
"Unfortunately, we have lost some track time, stopping running in the afternoon because of an issue on the car. Identifying problems like this is what testing is for and we will make further preparation to make up the lost time over the remaining three days."
Kevin Magnussen, who was keen to build upon his 132-lap total from last week's test session, rolled out of the garage promptly at 9 a.m. local time for some reconnaissance laps before a 15-lap timed drive on the medium tire. A switch to the softs was subsequently made, whereupon Magnussen performed three stints totaling 31 laps. It was during the first of those runs on softs where he posted his quickest lap of the day – a 1:21.298 on his 23rd lap.
Track time in the afternoon was ceded to an ERS (Energy Recovery System) related component issue. Time spent in the garage meant a shortened run plan, with Magnussen returning to the track with just over an hour remaining in the session. Working on a race simulation, he started with a 16-lap run on a used set of supersofts before pitting for a new set of softs which he ran for 17 laps. A final, 12-lap stint on new supersofts took his lap total to 96 for the day.
"It was a good day," said the Dane. "We got a lot of laps done. We started working properly with the car, and not just doing systems checks, installation laps and aero runs. I'd say it was our first proper day, also with the weather being a bit warmer and representative of what we're probably going to have in the season. It's still not quite there, but it's getting closer. I'm happy and positive after the day."
"A productive day today," aded Guenther Steiner. "We had a few small problems, but they are normal in testing, so I would call them minor ones and we got them sorted. We almost did 100 laps, which if we keep on going like this, we'll be fine."
Even though ultimate lap times were not the target today, both drivers were very closely matched on pace, with Nico's 1min 21.432secs just 0.023secs faster than Carlos.
"There's not much to say about my running in the morning," said Hulkenberg. "We did complete 49 laps, but we did have a few niggles with this chassis on its first outing; no big dramas and at least they were sorted quite quickly. I'm hoping for a decent run tomorrow afternoon."
"We completed a lot of laps in the afternoon and made good progress in understanding the car despite the wind, which was very tricky at times," added Sainz. "However, it's still very early days regarding set up as today was the first proper running compared to last week. Personally, I felt good in the car and it was great to get some decent laps under my belt. I'm looking forward to working with the crew on some different areas with the car tomorrow morning, where I'm confident we can make further improvement."
"We had a scrappy morning," admitted Bob Bell, the team's Chief Technical Officer, "and had to pull the car into the garage on a couple of occasions to check some things, so we didn't get the mileage we had hoped for this morning with Nico. We recovered well this afternoon and got a race distance in with Carlos. It was interrupted by a couple of red flags but we completed the distance and can be pleased with that. Overall a productive day."
"It's great to come here to some more normal weather," said Paddy Lowe at Williams. "We were running Sergey in the morning and Lance in the afternoon. Sergey had a bit of a slow start because we had a small problem with a bit of bodywork which lost us an hour to change some parts. Sergey managed some reasonable runs but with the warmer temperature, it's a bit windier this week so we had some tricky balance issues which we were not able to address during the morning session.
"Lance took the car in the afternoon with the objective to complete a race distance, which he did, taking it right to the flag. Lance's long run also included our first look at the hypersoft tyre. At the end, we also completed the FIA restart tests. In summary, we're very happy to cover a lot of laps today, including our first race distance with the FW41 without incident."
"We had warmer temperatures today but they were tricky conditions," said Sirotkin. "It looked like a nice day but it was not so easy testing-wise. We had a couple of little issues throughout the morning so it was not ideal, but for sure it was still better than last week and I still learnt something from it. We also got some data which will help us tomorrow with the stuff we're doing. Today was not ideal, but it is how it is."
"It was just good to do some kilometres in the car," admitted Stroll. "I have the first race distance of the year under my belt now and it was positive. I believe we have made a step forward compared to where we were last year with just the general feeling and grip level. I don't know where we will be compared to everyone else, but compared to last year's car, it definitely feels quite a bit better. So far, so good and we just need more seat time, quali sims, race sims and I believe we will be in a good place when we get our programme done and are heading into Melbourne. I believe we can still improve a little bit everywhere.
"There is still so much we haven't tried on the car yet. In a Formula One car you have so many set ups and it takes two weeks to get everything out of the way. I believe there are still little things we can do and again, it was a race sim so I can't compare that to what we were doing last week on lower fuel. There is still a lot to learn but race simulation-wise, I believe we are in a good place. But also, definitely these conditions are not ideal, as this smooth surface in Barcelona doesn't give much graining to the tyres, so I am sure it will be very different when we show up in Australia."
"It's been a good day of running," said Sergio Perez. "We tried several different tyre compounds and understood a lot more about our new car. I only have one more day in the car before Melbourne but today gave me a lot more confidence about where we are now, with both the car and the set-up. We still have a lot of work before we are where we want to be, but hopefully we'll be in a good shape by the time we arrive in Melbourne. It's difficult to say how we compare to the other teams because we are all on different programmes and fuel loads, but I am excited about this year; it's going to be very interesting. Pirelli have been quite aggressive with the compounds and that should give a lot more strategic options, which should hopefully make for some exciting racing."
"We had a very busy programme today," added Tom McCullough, the Silverstone outfit's chief race engineer, and the key objective was largely catching up on what we couldn't achieve last week because of the weather. It was good to have a dry day and to run reliably. Our main focus was on gathering critical aero data and we also started working on some set-up items ahead of the first race of the season.
"We are doing our own programme and just focussing on what we need. We are satisfied because it's been a productive day, but there's still a lot to do in the rest of the week."
Catching up on the track time that was lost due to the tricky weather conditions during the first week of testing, Marcus Ericsson completed a total of 120 laps in the cockpit of the C37. The team's main focus today lay in aerodynamic and mechanical testing, as well as tyre work.
"Overall, it was a positive day for us," said the Swede. "I completed a good number of laps, and the weather conditions were more representative in comparison to last week. We are continuing to understand the car and can see its potential. We have a lot of work ahead of us and are moving in the right direction. I look forward to getting back in the car on Day 3."
"We had a productive start to Test 2 today," added Jorg Zander, the Swiss outfit's technical director. "Marcus completed 120 laps, and we collected plenty of useful data. We completed set-up work and tested different tyre compounds, learning about their behaviour on the evolving track conditions throughout the day. The car update worked well, within expectations. The team is on a positive path and I look forward to what we will learn in the upcoming days."
McLaren suffered some niggling issues that meant running was relatively stop-start throughout the day. After an initial install lap as the track went green at 09:00am, Stoffel reported a loss of electrical power to the car and coasted back into the pits.
The same issue affected his next run, when after another three laps all electrical power to the car shut down, and Stoffel stopped out on track. The team investigated the issue and elected to swap the battery, after which Stoffel returned to the track just before lunch.
Despite a productive early-afternoon stint out on track, Stoffel's run was cut short with a suspected hydraulic leak just before 16:00hrs. Due to the location of the leak, the investigation and fix were naturally time-consuming, and meant the day's running concluded early. Nevertheless, he completed 38 laps and still managed to gather a lot of useful data in preparation for tomorrow's running.
"Today was challenging because of the issues we had which interrupted our running," said Vandoorne. "We had a few stoppages on track, and we've been working through each one to make sure we're fully prepared for tomorrow.
"The kinds of issue we've had weren't particularly serious, but have taken a relatively long time to fix, so we weren't able to run as much as we planned. The conditions this afternoon were quite tricky due to the wind, so the running we did wasn't so representative.
"We're hopeful the issues have been fixed and we can have a more productive day tomorrow."
"Today wasn't the day we had hoped for on track," admitted Eric Boullier, "but, despite this, we aren't overly concerned about the issues that we've faced today.
"It's obviously not the productive day we had planned, but the problems - a battery issue and a hydraulic leak - are the types of niggles that we almost hope and expect to face during testing, in order to prepare us properly for the season ahead.
"We are here to test, and today is what sometimes happens in testing. It's not ideal, and we would have liked more track time, but we're working on it, we're learning from it, and we'll return to the track tomorrow armed with more information."