Towards the end of the 2014 season it became clear that Mclaren was starting to get on top of its aerodynamic instability. With Eric Boullier's restructuring ongoing and with Peter Prodromou back in the fold, the general philosophy shifted from peak downforce to more driveability and more aero stability.
Boullier confirmed at Jerez that the car's design was mainly driven by ease of use: "We are trying to make sure we can give our drivers the ability to exploit the car to the limits, which means getting this performance package. If you have a performing car and a driver cannot drive it, then it is obviously a waste."
This translated into the 'all new' MP4-30, a car aerodynamically resembling several recent Red Bull Racing cars, thanks to the ton of knowledge that Prodromou brought with him to Woking.
The front of the car
The front wing looks very similar to the wing introduced for testing at the end of last season. They made a slight alteration to the trailing edge tip of the endplate, now bending more outwards, but for the rest it remains more or less the same.
The nose is again a totally different story as the modified regulations of the front crash structure forced everybody to rethink their noses. Mclaren came up with a very interesting solution that has several remarkable aspects:
(I) As also seen on the Ferrari SF15-T, the slope down to the nose starts much further back than before, most likely to reduce the agle of the nose as much as possible. Reducing this angle has the effect of reducing the pressure gradient of air flowing up the top of nose. This reduction in pressure gradient reduces the force of the airflow to "tumble" off of the edge of the nose and create turbulence going along the side of the nose.
It's interesting to note though that the slope is not linear and more flat towards the tip of the nose. Given that several teams are convinced that a shorter nose is the better aerodynamic solution, it may be that McLaren is preparing a shorter nose, featuring the upward slope of the monoque above the suspension pickup points.
The camera pods attach in a similar fashion to Mercedes and RedBull did last year. Probably trying to use them as flow conditioners for the airflow going up the nose and spilling off of the sides of the top of the nose.
The tip is low and flat which looks to be shaped to minimize drag. The nose is very rounded and looks to prioritize minimizing turbulence of airflow going around it, contrary to getting the absolute maximum volume of airflow under the nose. There are holes in the tip of nose, most likely for driver cooling.
The front wing supports are shaped as ‘scoops’. They draw in air flowing around the side of the nose tip and re-direct it underneath the nose. This will work in conjunction with the rounded nose tip. This looks like a very elegant and well thought out solution. The design of the front wing supports has been considered crucial for rear downforce and was particularly obvious on the high-nosed Ferrari F138.
There is a gentle large radius curve underneath the nose behind the front wing supports/pylons. This is designed to work with the ‘scoops’ and helps air passing alongside the nose to flow underneath the monocoque into an area that is naturally low pressure because of the low tip of the nose.
The area that shows McLaren's design philosophy change best is the new monocoque that, contrary to the McLaren MP4-29 is as high as possible before its slope as part of the nose cone. The transition actually forms a pretty sharp angle and is a distinct difference from the Ferrari SF15-T. In line with most car designs of 2014 and 2015, McLaren now believes the aerodynamic advantages now outweight the lower centre of gravity that the previous layouts gave them.
The front suspension has meanwhile retained its push rod actuator, in line with expectations. The suspension wishbones do have a slightly bigger angle than last year, a change possibly influenced by the higher monocoque. The new layout results in a slightly higher centre of roll and better anti-dive properties, but it's still a fairly conventional suspension layout. Also of note is how McLaren retained the high pickup point of the push rod, contrary to most other teams where the pickup points is located nearly in line with the pickup points of the upper wishbones. Such high position is always advantageous for the suspension set-up, as the more vertical wishbone results in a more downward force vector than layouts as on the Red Bull or Lotus.
The overhead intake looks slightly larger than last year. It is still split into an upper and lower section. There is not much to be said since the size of these inlets can't really be compromised without moving them completely.
The front of the side-pods feature smaller radiator-intakes than last year. Quite a bit smaller actually. Surprisingly, this has not caused any overheating problems on the car at Jerez testing, a property Eric Boullier proudly attributed to the team's engineering skill and their close cooperation with Mobil1. The latter developed oils that enable McLaren to run the engine hotter than was initially the case.
Above and around the sidepod entry, the car retains its two vertical vortex generators along with a seemingly very different shaping of the sidepod panel. It's particularly interesting to see that at the sidepod's shoulder, a bump houses the side impact structure, allowing the team to slim down the sidepod without being too much restricted by the side of the impact structure. The team has conveniently connected the sidepod panel to this extension as well.
Behind a fairly large undercut at the front of the sidepods, the middle section features much less of an undercut, hardly a surprise given the overall dimensions of the sidepods themselves. It’s quite surprising at how slim the side-pods are, somewhat reminding to the 2013 Sauber ones and extremely similar to the concept of the Red Bull RB11.
Finally, it's interesting to note that the sidepod panel now extends all the way up to the maximum height whereas cooling vents alongside the cockpit aperture are no longer being used.
Floor and rear of the car
There only seems to be one simple flick-up at the front of the floor at the sides. Cut-outs in front of the rear tyre look to be the same shape but look to be slightly larger than last year. This seems to be a design that works, as all the teams who tried it last year, kept it. The floor around the rear tyres features a very interesting shape. There don't seem to be any vortex generators currently, but we can expect McLaren to feature a couple of those later on.
The cooling outlets look very similar to RedBull last year and this year with a central outlet around the exhaust and two lower flatter outlets around the suspension. We don’t have pictures of the radiator layout or internal aero work yet, so it remains hard to judge this aspect.
The rear wing DRS flaps have the same leading edge serrations as run at parts of last year.
The wing of course is subject to more change as testing progresses, but the central support that was missing on the car's launch pictures returned for testing at Jerez, supported by a coated carbon fibre bridge over the exhaust pipe. The top of the rear wing endplate features the usual drag-cutting horizontal slots above the rear wing. In addition to this there are vertical slots below the rear wing. The small row of vortex generators are still there from last year.
From overhead shots it looks like the rear suspension mushrooms, or rather its position, are still there on the lower suspension arms. McLaren already removed the mushrooms on the upper suspension arms halfway through the season and have tested at Jerez mostly with conventional wishbones and track rods, aimed solely at limiting drag.
The launched car pictures however still features uncommonly shaped track rods, suggesting McLaren may still end up racing them. The team did evolve them compared to the MP4-29 and it looks as if the mushroom section does not extend right to the centre of the diffuser. This may indicate that the purpose of these mushrooms is to both turn the airflow upwards and direct airflow towards the centre of the car above the diffuser. It’s the belief that it has something to do with the design of the diffuser.Text by Alex Weedon, Andy Urlings and Steven De Groote
Image edits by Steven De Groote