Even though development scope was severely limited this winter, Mercedes still appear to have gone all out in the areas where there was still room for development. In fact, Technical Director James Allisson confirmed the team had spent its two development tokens, but didn't want to give away just yet where the team had done so, saying "it would become clear in due course".
As ever, the released renderings of "launched" cars these days hide a lot of secrets, with bodywork updates all over the car expected to appear on the Friday of the first race weekend at Bahrain. The actual car displayed in the team's video had the car's floor covered, a seemingly very sensitive area.
"The floor is where the regulations changed the most, as the FIA tried to reduce some rear downforce", Allison said. "But, we'd rather not show our solutions here to avoid other teams trying out the same ideas in their wind tunnels. Let's just say it buys us a few weeks time."
The front end of the car continues to feature the same design philosophy including a nearly identical nose cone with cape and a visually unchanged front suspension. Mercedes did however modify the front brake ducts in such a way that the bottom is now the widest section, whereas previously that widened inlet used to be at the top.
The barge board area is very likely to still change, and even the sidepod's shape and engine cover has often been changed on many cars in between the launch and first race. Of note however on this Mercedes AMG F1 W12 is a particular bulge in the engine cover. The team's Technical Director fuelled speculation even more by saying this was where the guys from the power unit development needed some extra space for more power.
Indeed, long before the launch, it was leaked that the outer shape of the power unit, as communicated to the customer teams, had changed considerably for what is expected to be a modified inlet concept. In line with this change, the airbox also appears to have become a bit more bulky compared to the 2020 car.
Those small bodywork changes are but the tip of the iceberg, as Thomas Hywel, Director of Mercedes High Performance Powertrains uncovered a bit of what the team had done over the winter to overcome some of the problems the team endured with its power units in 2020, and especially in 2020 pre-season testing, where Mercedes was particularly struggling badly with reliability.
“We’ve completed some work on improving the reliability of the PU,” he said. “In 2020, we used an aluminium structure which wasn’t as reliable as intended, so we’ve introduced a new alloy for the engine block.
“We’ve also made some adjustments to the Energy Recovery System, to make it more resilient. We’ve got a big challenge in 2021 with 23 races on the calendar, we will need to ensure that the reliability of the power unit is spot on. We’ve worked hard on that area and hopefully it’s paid off.”
“We introduced a complete redesign in 2020, a very different MGU-K to what we had run previously,” added Thomas. “It helped us make a solid step forwards in performance, but it was a design that turned out to be difficult to manufacture and assemble consistently.
“We had lots of examples where the MGU-K ran a full cycle and did exactly what we wanted it to do, but we also had some cases of midlife failures. For 2021, we’ve gone back, looked at that design and built an understanding of where the failures have come from.
“We have changed it for this year, to allow for a more consistent manufacturing route which should help to improve the reliability of the MGU-K.”
“We’ve got some completely new innovations that will be in the racing PU for the first time,” he said.
“That was particularly challenging because last season finished late, so the winter period has been shorter than normal and has given us less time to prepare, which put extra strain on the business.”
He added: “We’ve continued our quest for better thermal efficiency in the internal combustion engine. Most of the developments can be found in the core of the power unit, with a desire for maximum output from the combustion process.
“Hand in hand with that, we’ve introduced changes to the turbocharger to minimise the impact on the heat rejection. Those are probably the most striking when it comes to crank power and the performance of the power unit.”
Overall, Mercedes appears to have put considerable work into their power unit to make sure their cars can last 23 races with just two power units. This change also made it important to have as much updates as possible available at the start. But again, all this was further complicated by the regulations as these restrict the number of dyno runs that can be done.