Just 48-hours after its total domination of the Bahrain Grand Prix, Mercedes was back in action at Sakhir leading the way in the first in-season test of the year.
Nico Rosberg, who finished second to teammate Lewis Hamilton as the German team scored its second successive 1-2, topped the timesheets today as well as completing the most laps.
For the Brackley-based squad, today's programme consisted of running through numerous set-up evaluations. Rosberg emerged for his first run at 09:15, completing 70 laps in the morning before completing a further 51 laps in the afternoon, as the team continued running right up to the chequered flag at 17:30.
Between them, Mercedes-Benz power units, which filled six of the first eight positions on Sunday, completed a total of 1,732 km today.
"Our main aim today was to try different directions with set-up and to get to know the tyres a bit better," said Rosberg. "You never stop learning how to get the best out of the tyres, so it has been a productive day from that perspective. We also did a bit of work on the brakes as this is an area I'm not one hundred percent happy with at the moment.
"We've had a good few weeks on track but you are never at the maximum level of performance," he insisted. "There is always more to be found and we are constantly pushing to improve the car and also ourselves as drivers. Having said that, the team are doing a fantastic job with this car from every perspective. Reliability, car performance, Power Unit performance: it's all there and it's a pleasure to be a part of a team with such positive momentum."
Having taken the third podium spot - the best that is currently on offer as far as the opposition is concerned - Force India maintained its form, Nico Hulkenberg completing 69 laps on his way to posting a best time just 0.367s off Rosberg's best.
Concerned at his team's start to the season, particularly last weekend when it could only manage ninth and tenth, Fernando Alonso is on duty for both days of the test.
In the morning, the Spaniard concentrated on fine tuning various electronic configurations and on taking aerodynamic measurements with constant speed runs down the main straight. In the afternoon, work was carried out in short runs, lapping to evaluate different set-up choices.
Running numerous odd-looking sensor devices over the course of the day, the Maranello outfit was the cause of a red flag period when Alonso stopped on trach mid-morning.
As previously reported, in the interests of driver continuity, McLaren changed its line-up, giving Kevin Magnussen both days in the car as opposed to the original plan which would have seen Oliver Turvey test today and Bahrain GP2 Feature Race winner Stoffel Vandoorne driving the car on Wednesday.
With the in-season tests focused primarily on mileage, reliability running and component validation, the Woking outfit took the opportunity to undertake in-depth analysis in order to broaden its understanding of MP4-29.
Despite making some lengthy set-up changes to the car between runs, Magnussen managed to complete 102 laps and post a best time 0.937s off Rosberg's pace without problem.
While Valtteri Bottas finished the day fifth quickest, the Finn only completed 28 laps over the course of the day, however, the Grove outfit says it is pleased with the day's results.
"We had good mix of tests today with aero, mechanical, car set-up, electronics and power unit, and we managed to get through everything which is hugely encouraging," said Rob Smedley. "The results were very positive and we collected a lot of good data, which is good news. Valtteri also did a good job for us today. We are pleased to be running here as it has given us that chance to build on the data from the weekend and means we have continued development from the start of the race weekend. Felipe Nasr will be in the car for us tomorrow as we complete a 2015 tyre test programme for Pirelli."
"Overall it was a good day as we managed to complete the programme as planned," said Bottas. "We then worked on set-up and we were quite experimental, so hopefully that will help in the next few races. Next it was time to test some new aero components with some positive results. The track conditions were different from the race, but actually better for testing as there was less wind.
His 100% finish record intact, Max Chilton finished the day sixth quickest, ahead of the Red Bull, the English youngster completing 60 laps as he and the Russian team worked through its development checklist.
"Generally we've had a positive day in which we've completed the programme and developed the car a further step in only a short space of time," said Chilton. "We did have a hydraulics issue which stopped us for a while but this was fixed quite quickly and, in actual fact, the period for which we were confined to the garage was when the track was at its hottest. We were able to keep our tyres back until later in the day and make use of them when the track was a bit more usable and representative. I'm pleased with the timesheet at the end of the day, especially since there was room for improvement with my quick lap."
"After such a positive outcome to the race on Sunday, Max was naturally keen to be back in the car as soon as possible and get into the testing items that will hopefully contribute to us maintaining the momentum in China next weekend," added Chief Engineer, Dave Greenwood. "We have a comprehensive programme for this test, which began today with aerodynamic measurements and moved into set-up programmes exploring mechanical and aero changes. In the background we continued with mapping work and an evaluation of some revised parts for electronic reliability. Aside from a hydraulics issue, the first day has been productive and we look forward to continuing the progress with Jules tomorrow."
Although 2.6s off the pace, Daniel Ricciardo did put a further 91 laps on the RBR10 as Red Bull's fight back continues, the Austrian outfit having made dramatic progress since the pre-season tests here.
"We missed a little bit of time this morning but we made up for it in the afternoon," said the Australian. "We didn't get in any performance runs today but we did some good long runs in the afternoon with three set-up changes and we got some good feedback from that.
"I think during last weekend we struggled a bit in P1 and P3, the daytime sessions in the heat, but the car felt a lot better today in those conditions, particularly on those long runs. We're still a little behind but we're chipping away and I'm sure over the course of this test and in China we'll get a little bit closer. For the moment, though, we'll take every little bit we can get. We're learning and we're making progress."
"An excellent day today," said Race Engineering Co-ordinator, Andy Damerum. "We were a little delayed in getting out this morning but that was simply down to the amount of instrumentation involved. Once Daniel was out though we worked through a very packed schedule of items and over his 91 laps we managed to tick off almost all of those things.
"There are many little standard test things which we couldn't get done in pre-season and which the nature of race weekends don't allow for, so today has been very valuable in terms of working through those items. So, all in all, a busy first day and it will be more of the same tomorrow when once again Daniel will be at the wheel."
Sauber, which had a disastrous weekend at Sakhir, enjoyed an altogether better first day of testing as Sergey Sirotkin drove the C33 for the first time. In the morning the Swiss team focussed on aero work including measurements while in the afternoon the team switched focus to long runs. Sirotkin completed more than 300 km, which is a requirement to receive his super licence.
"It was a good day," said Paul Russell, the Swiss outfit's Test Engineer. "We did everything we wanted to do and completed our programme. In the morning we did some aero measurements and the procedures went well. With the new medium tyres Sergey continuously improved his lap times. We practiced all the procedures associated with the car.
"With the new power unit there is a lot to do for the driver. As he had not driven the car before and did not know the track either, he had a lot to do in the cockpit. Sergey had to learn all of this and he handled it pretty well. The lap times were very good. He seemed to be learning the car and the track quite well. In the afternoon, we continued our programme and finished the day with the long runs. All in all, it was a positive day."
"Everything felt great today," said the Russian youngster. "It was the first time for me in Bahrain and I liked the track. In comparison to what I am used to driving in World Series by Renault, I have quite a lot more engine power and more acceleration with the Sauber C33. On my fast lap in the morning I made a few mistakes, so I probably lost a second. But all in all, it was a good start to the session.
"In the afternoon we had some difficulties with my shoes," he admitted. "They were too small, so it was pretty painful when I was braking. When we changed the shoes, it was still not the best and difficult to drive. It was not easy, but I am glad we completed the 300 kms. We know that there is a lot of potential for improvement and we should all be happy with this."
Over the course of the twelve days of in-season testing, each team has to dedicate one whole day to tyre testing for Pirelli, today, the first day of in-season testing, that role fell to Caterham.
Unfortunately, the team, which has had a difficult start to the season, continues to experience problems and as a result of a hydraulics issue the session, which saw Robin Frijns on duty, was brought to an early close.
"I'm glad we managed to complete 63 laps this morning but it's obviously a shame we couldn't add to that in the afternoon," said the Dutch driver, "especially as I felt good in the car and was enjoying myself. When we finished the last run before lunch we found a hydraulic system leak that meant the guys had to take the floor and gearbox off and with the time it would have taken to rebuild the car we made the call to end the session early so we could prepare for day two.
"There's not much I can say about the tyres we were running today as they're obviously development sets and because it was a Pirelli test today we weren't aware of what compounds we were running. Now Marcus takes over for tomorrow, our last day on track in Bahrain this year, and we'll aim to have a clear day of our own test so we can leave Bahrain with as much information as possible from our last day here."
It was a problematic day for Lotus also, Pastor Maldonado's work coming to an early end due to power unit-related issues. The Venezuelan completed just sixteen laps, with a best lap over 4.4s off the pace.
"This morning our programme was focused on aerodynamic work and we achieved a lot, even with a limited amount of laps," he said. "This afternoon the plan was to work on performance, evaluating parts and set-ups, however we have not been able to run though the programme due to power unit issues.
"We need to check and understand what has happened," he added. "This is what testing is for even though we would have preferred to have been able to complete more laps today. I hope that Romain can continue to work on our testing programme tomorrow and hopefully have a more positive day."
"Unfortunately we weren't able to carry out the programme we had set out to do today as two power unit related failures stopped us far short of what we wanted to achieve," admitted Alan Permane. "Of course, this is frustrating for everyone involved, but our focus is now very much on getting the most we can out of tomorrow."
Failing to score his third successive points finish at the weekend, Daniil Kvyat was on duty for Toro Rosso as the Faenza team focussed on chassis work over long runs. The main aims were to move forward on the development of the car in race trim as well as give the Russian valuable extra mileage under race conditions, in addition to carrying out tyre work.
"Even if you can't see it from looking at the timing screen, this was a productive day during which we learned a lot," said Kvyat at the conclusion of the day's running. " It was very useful for me, giving me a lot of laps away from the race weekend environment. We also learned something about why our pace was not as strong as we had expected in Sunday's race. I think this in-season testing is a very useful thing, not just for the teams, but also for guys like me who have to catch up in terms of experience."
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