McLaren have long since followed their own path in aero development. Certainly since 2009 the car has increasingly diverged from other team’s aero concepts and the 2012 MP4-27 is no different. However the current car has a clear lineage in some of the design solutions and the whole front end is an evolution of recent cars.
Their first car to the current aero regulations in 2009 sported a conventional nose, front wing and cascades.
The car that was launched in 2010 had a very different front end. The drooped nosed of the MP4-24 was gone replaced by a more horizontal and shallower nose cone. Beneath this was fitted large aero device, I term a “snow plough”, Williams had run a similar solution in 2009.
From a horizontal leading edge positioned between the front wing mounting pylons, the snow ploughs surface splits into left and right sections and eventually forms a pair vertical vanes protruding below the nose. This creates a “V” section mid way along its length and the twist of the airflow along with the pressure differential between the upper\lower surfaces creates vortices trailing from the rear of the vanes. This is an aggressive solution compared to the simpler turning vanes other teams use. This device probably creates some downforce in its own right, but I suspect the primary purpose is to direct the strong vortices along the Y250 axis, to drive a better airflow towards the floors lower leading edge.
Later in 2010 after a series of different iterations of endplate and cascade design, the wing substantially changed for Singapore GP. The main plane was effectively split into two; a section ahead of the front tyres and a section inboard of that. The intersection between the sections formed an upright for the main cascade winglet. While the less aggressive inboard wing span gains a simple “r” shaped vane.
McLaren continued the 2010 design of snowplough nosecone and split front wing into 2011 with the MP4-26. Again later in the year, the wing was simplified for the Indian GP with similar endplates and cascades, but the complex split shape wing profile was changed to be straight across its width.
Again this format was brought forward to the launch and initial test version of the 2012 MP4-27. Only in the last days of Barcelona testing did the revised front end appear. Gone was the snowplough and the straight wing profile. In their place was a simpler nose cone and a pair of vanes dropping vertically from the nose. While the more complex split wing profile was reintroduced. With EBDs less powerful this year, teams are finding downforce levels are lower. We could conclude that the snowplough and straighter wing arrangement were better for downforce, so the new simpler arrangement may be a more efficient way of producing less downforce.
The other change in China was the deletion of the slots in the small cascade winglet. The slots would have reduced the strength of the vortex produced by the winglet, removing the slots will have increased them. This change will be made in order to direct a stronger airflow around the inside face of the front wheel.
As the team get to grips with the new exhaust regulations and start to develop more downforce, potentially some of these solutions could return. So any reappearance will tell us a story of development and aero load figures in 2012.