TopGear drives the DeltaWing

But I'm getting away from the point here, which is that less weight needs less tyre width, as the forces acting on it are so reduced. So it uses Citroen 2CV-dimension front tyres, each just 100mm wide. It also uses real 2CV front tyres. Michelin is so protective of the technology it's developed here that it will not leave the team with the race rubber, but instead lends them some ancient, heavily treaded 2CV tyres so Deltawing has something to trundle around the paddock on.

So that's the tyres, what of the aerodynamics? "It's very odd," Bowlby tells me. "You think a teardrop is the best way to go, but the dart shape makes a very rearward centre of drag - even further back than the centre of mass - so you have a stabilising effect like a weathervane. So when you drive it, what you feel is a tendency for the car to be undramatic."