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Today in Paris the International Court of Appeal has been hearing the two sides of the debate into the legality of the so-called double decker diff...

Motorsport Blog

Motorsport Blog

Today in Paris the International Court of Appeal has been hearing the two sides of the debate into the legality of the so-called double decker diffusers, as used by Brawn, Toyota and Williams.

It all got quite passionate as the lawyers for Ferrari and Renault in particular stated their cases.

Andrew Ford for Renault said that the FIA had already established that a design which incorporated holes to improve the efficiency was illegal in F1, "It is not that Renault missed the boat, as Brawn have pointed out, it is because the FIA said it was illegal. It was at that point the diffuser was abandoned,"

This all goes back to a ruling the FIA made in 2001 about a design on the Williams car and a subsequent clarification the FIA issued in 2002 about where holes were not permitted in the floor. The three diffusers under scrutiny now, exploit a loophole in the wording of that rule.

There seems to be a fair amount of confusion in the media over what might happen if the appeal is upheld and the diffusers are banned.

The problem is that there are many possible outcomes, which the court has the power to impose. The most extreme is that the cars with the trick diffusers could be disqualified from the results of the first two races.

Another possible ruling is that the points from the first two races could stand, but a ban on the diffusers could come into force at the next Grand Prix, this weekend in China. Or, given the logistics involved a ban could be deferred to the Bahrain or even Spanish Grand Prix.

Another possibility, which would really cause confusion and unhappiness among the teams, is that the court could rule that the FIA should clarify the technical rule, thereby putting the ball back into its court.

Such a clarification could take several weeks and leave the teams in a kind of limbo through the remaining fly-away races and the early European ones.

This outcome would be very hard for the public to understand.

If the appeal is thrown out, then that is the end of the matter and the other teams will have to copy the double decker design and accept that they have lost the first part of the season.

A lot is at stake here, the difference in performance between the double decker and a normal diffuser is 15%, which equates to around a second per lap.

The plaintiff teams believe that the double decker violates both the letter and the spirit of the rules and are particularly aggrieved by the latter as the whole point of establishing the 'overtaking working group' was to find a joint teams' solution to the problem of overtaking in F1. The teams worked together to find a way of making the cars more easily able to follow each other and overtake and part of that was an acceptance that the effect of the diffuser needed to be reduced by half and that it should not interact with the rear wing.

These diffusers fly in the face of that joint initiative.

The three diffuser teams argue that once the rules were set and defined, it was up to each team to find the loopholes and devise the cleverest solution, as has always been the practice in F1.

The word is that the idea of the step, or double decker diffuser was dreamed up by an aerodynamicist at Honda, who then moved to Toyota. Honda became Brawn over the winter and that is why the Brawn unit is the most sophisticated and effective,  because it is the one which has been under development the longest.

The ICA is due to make its ruling some time tomorrow.
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