My remarks about the lack of overtaking in Abu Dhabi resulted in a lot of reaction. Among the responses was a email from Clive Bowen, who is the boss of Apex Circuit Design, which does a lot of work in racing, although Hermann Tilke continues to get much of the F1 work, for reasons that are not entirely clear. Bowen reckons that “research and liaison with teams and drivers” has genuinely achieved good results in his projects and he believes that the secret is to design the track geometry “to ‘build in’ confidence and grip for drivers just where they need it the most to make a pass”.
Bowen reckons that there are three ways to create more overtaking when one designs a circuit; the first is to ensure an ‘easy short apex, low-medium speed’ corner preceding a long straight which leads to a big braking zone. The key is the short apex as it results in the least period of feathered throttle; if the transition from braking to acceleration is as fast as a driver can make it then the car following can keep closer to the car in front at the start of the acceleration run and his opportunity for a tow is increased… a medium speed (i.e.120kph or so) corner with mechanical grip provided by banking or compression allows the following car to stay close despite wake turbulence and reduced aero grip.
The second way is to engineer grip into a corner – achieved either with compression or banking – just where a driver needs it to give confidence for a manoeuvre. This and the third option (or a combination of both) should result in more than one ideal line for a corner or should at least ensure an overlap in the braking transition into a corner to spoil the guy in front’s line.
The third is to have compound radii in corners – especially those where the apex can be made to be really late; this means the ideal line leaves the ‘door open’ for an opportunistic pass.
A subtle combination of all three – and different each time – is the best solution. This should mean some corners have multiple lines (i.e. same time through the corner irrespective of line), some other corners can act as mistake generators to spook the guy in front to overdrive and create the opportunity for passing and any other corners should instil confidence for a driver to be braver than he might otherwise be.
Bowen says that “I suspect it is the subtlety of a track’s corner sequencing and detail which affects its personality and this in recent times has been lost because of modern design processes”.