Ferrari were the first team to move the wing mirrors from the conventional spot near the cockpit to the edge of the sidepods. Since then most teams have at least trialled the set up. From the next race in China, this mirror location will be banned. Always a controversial part as many see their location and more flexible mounting as hindrance to rear visibility. During their reign the FIA even introduced scrutineering tests to ensure the driver has reasonable rear visibility. But all the problems associated with these mirrors is worth it due to the beneficial aerodynamic location.
A wing mirrors on any vehicle is a bluff and unaerodynamic shape, from the attached CFD you can see how its wake is unsteady and turbulent. The FIA demands mirrors are fitted with a reflective surface 150mm x 50mm this creates quite large surface to streamline. In a conventional position this sends the wake directly downstream towards the rear wing, upsetting its efficiency. Placing these outboard places the mirrors in the already turbulent area of the front wheel wake. Thus the impact of the bluff mirror housing is reduced. With the change in Aero rules in 2009, the mirror placement in this area allowed the pod wing to be taller and have a greater aero influence. However even with the ban on the mirror locations the fin-like podwings will remain, as they sit in a blind spot within the bodywork regulations.
It was Ferrari that first introduced the outboard mirror, on the launch version of the F2006. Initially the mirrors were on their own arched mounting (itself acting as a small turning vane), as pod wings were not universally adopted. Over the subsequent years many teams have adopted the mirrors. The following year, Renault with their R27 placed the mirrors directly onto the pod wings. It was this later development that visibility problems first really occurred, the pod wing needed additional support to prevent is wobbling at high speed. At the time Renault Aerodynamicist, Dino Toso told me he believed the mirrors would actually provide a better view, as the mirror was further from the driver, the vibration would affect the view less than a mirror close to his eyeline. Toyota found a halfway house by using the early Ferrari type mounting, but placed mid way between the cockpit and the edge fo the sidepod.
As other Aerodynamicists sought to reap the same gains, the drivers often rebuked the new mirrors. Adrian Newey frequently brought outboard mirrors ont he Red Bull, only for the drivers to opt for visibility over performance. Toyota equally tried mirrors in all three positions (cockpit, midway & outboard), Toyota’s consultant Frank Dernie told me “All the drivers I have worked with have refused to use them and asked for conventional ones”.
Although there’s a damning case for the visibility from outboard mirrors, that is not to say that conventional mirrors are much better. From on board shots we can often see the mirror resonating at high speed, from the engine vibration and the harshness of the ride. Obviously in this mode, the mirror cannot provide a decent rear view.
This year Mercedes, Virgin, Renault, STR, Lotus all run conventional positions. While McLaren did try pod wing mirrors at the last race and elected not to run them. At the time McLaren stated “We made a decision after P3 to remove them. Not sure yet if they’ll be making a comeback”, but this may have been because of the impending ban.
There is a performance loss with the re-siting of the mirrors for the other teams, but this will be measured in no more than a tenth per lap. the change is not likely to upset the teams order.
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