The Woking based Formula 1 team, McLaren, have recently revealed their new innovative suspension to the world during pre-season testing in Jerez, Spain. The suspension does little to improve upon any mechanical grip, as one may suspect; instead, the clever suspension improves downforce by acting to supplement the recent loss of the beam wing.

A recent regulation for 2014 aimed to do away with the beam wing. The beam wing ran across the width of the chassis, in between the rear-wing endplates. This wing created downforce on its own and helped structurally support the rear wing, but perhaps more importantly, it helped the airflow running through the rear diffuser and rear wing act together by creating a single larger upwash of air.

The Shroomspension (as I've just now coined it, though it has also been called Wishbone Wings and Butterfly Suspension) aims to fix this lack of a beam wing by inducing two wishbones with a cross-sectional outline shaped like a mushroom. As you may have noticed from F1Technical's illustration, each wing is angled 5 degrees upwards, so as to induce upwash from the back of the wishbone.

With something that looks effectively like a giant plane hanging from the back of the MP4-29, you may wonder how the Shroomspension doesn't create a massive amount of drag that would otherwise overpower the increase in downforce. A few reasons...


Air would otherwise have rushed in from the sides to fill in the low pressure zone behind the wishbones, but the rear-wing endplates seal out this from happening extensively. The wishbones are also aided by another wing (possibly approaching winglet territory) mounted low down near the floor that create another upwash of air directed just behind the wishbones.

The result is a suspension that helps replicate the beam wing, though not nearly as efficiently, by attempting to tie the rear wing and diffuser to each other.


This is the first unforeseen technical innovation of 2014, and may prove to be this year's double diffuser, F-duct, open-throttle blowing, etc. More importantly for McLaren, the Shroomspension is difficult to copy due to its geographical interaction with the gearbox:

McLaren have designed their rear suspension so that these rear wishbones are as much to the back as possible, attaching to the very rear of the gearbox housing. The [team] have therefore also been unable to combine the driveshaft with the lower wishbones like Red Bull and Ferrari have done. It is exactly this suspension geometry that would make it extremely hard for other teams to simply copy the design, as it would require redesigning the gearbox, the rear suspension mountings and the suspension wishbones, creating a combined impact on aerodynamics and mechanical behaviour that will take time to verify and optimise.

This may turn out to be the innovation that tips McLaren's anti-podium 2013 season into the 2014 season's Constructors Champions.