The Spanish GP is usually the venue of the introduction of the first significant development packages of a season. This year, Red Bull was expected to launch a heavily upgraded car after its woeful start to this year’s campaign. The energy drink-owned team brought some aerodynamic changes to its challenger, but it was Mercedes that drew most of the attention to itself by a major front end aerodynamic update.
The biggest change visually is the car's narrow nose, which obviously had to undergo a separate crash test before it could be used on track.The narrower version means there is a well-marked transition at the front bulkhead, where the detachable nose cone meets the front end of the chassis. Under the nose section, there is a very elaborate turning vane, already nicknamed 'teddy cape', to manage the turbulent wake of the front wing.
The way Mercedes engineers are paying attention to the details is clearly showed how the camera mountings were updated for this race. The construction of those mountings, and the exact position of the camera hubs are tightly regulated, but Mercedes still found a way to create slender mountings that provide the least possible obstruction to airflow passing aside and just on top of the nose cone.
Similarly at the front, the brake ducts evolved, with a different 2-element winglet now present on the suspension support arm, along with a revised shape of the inlet fairing.
The car's floor also underwent considerable changes, with the barge board getting a similar upgrade to work together in front of the sidepod. Together, they manage the vortices coming off the front wing and attempt to cleanly direct airflow underneath and around the sidepods. The complexity with serrated extension has made it nearly impossibly for teams to introduce modified barge boards without also adapting the floor, as both are extremely dependent on each other.
For the Spanish GP, the bargeboards got even more sophisticated. Three vertical vanes are now placed on the horizontal plane of the bargeboards. There is no other bargeboard which is close to the Mercedes’ solution in terms of complexity and serration.
Further back, the floor also features an additional small vane directly ahead of the rear tyres to direct air away from the turbulent area. That section of the underfloor was already rather complex with nine cuts along the side-edge. And for another extra bit of downforce, Mercedes also added a monkey-seat after running the W08 without one so far.
Mercedes also worked on its engine. It brought an updated power unit to Barcelona. The upgrade is aimed to improve the reliability of the Mercedes W08 EQ Power+. It can, however, have an impact on the power as well since it can allow the drivers to use the power unit closer to its maximum for a longer period of time in race conditions. Both drivers got new internal combustion engines, turbochargers, MGU-H and MGU-K units which are all only their second of the season. However, Valtteri Bottas had to revert to its previous ICE before qualifying. He later blew that engine, which was used in the first four races of the season, during the race.
Still, that's not the end of the story. Having been overweight at the start of the season - partly due to an overweight gearbox - the team focused on shedding some of that. 3kg was reportedly shaved off with the Barcelona update. That's only part of the way however, as Hamilton admitted after the race he did not have a drink bottle onboard for weight saving.