Tech Analysis: McLaren MP4-31 Honda
McLaren is out to bounce back firmly from its hugely disappointing 2015 campaign, and if first testing signs are to be believed, they are on the right path. Certainly in terms of reliability, the first two days of testing have proved to be a massive step forward for the team. Obviously, a large part of that improvement is down to Honda, but it's obvious that McLaren themselves have also made strides in the chassis department.
Starting from the front, the space around the nose tip has been increased. The nose flanking the thumb has been raised to allow more airflow underneath. This now makes it arguably the shortest nose we have seen on any F1 car this season, and it certainly looks like it is less of an obstruction to airflow underneath the nose than designs of Ferrari or Williams for instance.
Further proof that the team is aiming to get as much flow under the nose is easy to find in the front wing supports. These uniquely include a slot that allows air flowing on the outside of the supports to join underneath the nose. The curved shape of the supports where they attach to the nose cone also need little explanation on how these work airflow to flow towards the car's centreline.
The front wing currently on the car looks very much like one of the variants used at the end of last year. As is common in testing, teams usually introduce new front and rear wings towards the end of testing, so let's not focus to much on this bit for now.
Slightly further back we find McLaren's S-duct, introduced last year and unsurpisingly retained, including its split outlet alongside the pitot tube mounting. It does however look like the exit has been moved further forward on the nose, slightly surprising given that it's now even further away from the angle change atop the nose cone. The angle change looks as though it is has increased somewhat, maybe in conjunction with the (vertically) narrower front crash structure/nose, McLaren are trying to maximise the effectiveness of the floor.
The front suspension is another point of interest, and looks to be like a major target for improvement during last the winter. McLaren have clearly kept was was good, retaining fairly simple - almost old fashioned - suspension arms all around while perfectly aligning the steering arm with the upper front wishbone. What's interesting is that McLaren have decided to move the push rod attachment point backward, enabling for a higher position of the rocker that is located within the chassis. This means that the push rod is now more vertical, making for a better overall layout as one is only interested in the vertical movement of the wheels.
The other interesting modification is the lowered rear wishbones. It is not entirely clear to me how this could have any big impact on the suspension itself, so I presume this was done because the push rod now runs backward slightly - from wheel to chassis - or for aerodynamic gains. Or a combination of both.
In the cockpit area, the most obvious change is a redesign of the airbox, which is now more circular. It appears to have been reduced in size as well, while an aperture underneath this main inlet was opened up considerably compared to last year.
Images show that the airbox is still seperated in an upper and lower part, with the lower section feeding combustion air to the engine, while the upper section cools ancillary components located behind the engine. As for the smaller inlet below the airbox itself, we can only guess, but there are a few possibilities:
- more airflow to some critical components/areas on the PU that may have not received enough last year (or simply to cope with increased capacity from more powerful components) such as the between the V or the MGU-H.
- works in conjunction with the larger space mentioned between the sidepods and vertical section for (relocated) components.
- feeds a relocated cooler.
From a structural point of view it is worth noting that McLaren have managed to remove the external rollhoop supports, without a doubt the result of numerous hours of simulation and optimisation to make sure that the part is strong enough to withstand the upper impact test - to make sure the driver is save when the car rolls over.
Further back, McLaren has managed to retain an impressively compact rear end, benefiting from Honda's sub-zero packaging philosophy. Behind and in line with the raised cockpit protection elements, the shoulders do appear to be slightly bigger than before, most likely the result of repackaging to make room for the larger turbo on the Honda power unit.
Finally, in the exhaust area, McLaren have opted for the most popular design of putting two smaller wastegate pipes below the main one. They have also opted to copy Toro Rosso's idea to design the rear wing support such that is protrudes the main exhaust pipe. This obviously provides an aerodynamic advantage, as the supporting element that would otherwise be needed can be made lighter and thinner.
After the second day of testing, Fernando Alonso did say he was "proud of what the team have achieved over the winter". He did however also note they cannot draw conclusions yet about the car's performance, as his laps today were all about temperature checking and aerodynamic performance evaluations, or as he said himself "not very exciting for a driver, anyone can do these kinds of laps".
The car is out, but the verdict will have to wait until Melbourne, at earliest.
With thanks to Alex Wheedon for part of the analysis