Downforce isn’t beautiful. Up until this year we weren’t sure. Then the Senna arrived, its appearance mostly aquatic bottom feeder with a dash of kitchen implement, and it was settled. Downforce is ugly. But form follows function, and McLaren is good at function. And the function of the Senna is to go very fast indeed around a racetrack. And these days the equation between power and grip is only balanced by adding downforce. Eight hundred kilos of it in the case of the Senna. Now, delivering downforce is not difficult – just fit a bigger wing, a longer splitter, a larger diffuser. But at that point road cars run headlong into regulations. Regulations that demand pedestrians can’t insert their heads into bits of bodywork, cut themselves on edges or have vital anatomical bits severed.
And that’s what makes the Senna such an achievement. That rear wing, top-mounted to keep its key downforce-producing underside cleaner, made entirely of carbon fibre, weighs only 4.89kg, yet can support over 100 times its weight. It can move through almost 90º, managing the Senna’s centre of pressure, the airflow carefully guided as it approaches and departs. It defines the Senna. Not pretty, no. But astonishingly effective.