Teams in double diffuser race

The outcome of the 2009 formula 1 World Championship depends on how quickly and effectively the traditional front-running teams can develop and introduce double diffusers as they attempt to rein in Brawn GP.

A decision by the FIA Court of Appeal on April 14 backed up the earlier verdict by race stewards in Australia and Malaysia in confirming that the route chosen by Brawn, Toyota and Williams is legal. The seven other teams are now in a race against time to modify their cars. Renault introduced its prototype on Fernando Alonso’s car in China, while revised packages from McLaren and Ferrari will make their debut in Barcelona.

Although most insiders acknowledge that there is more to the Brawn BGP001 than the double diffuser – and Red Bull Racing has established itself as the second-fastest team while running to ‘standard’ spec – the other teams agree that the devices offer an instant time advantage.

The overall aero balance is also altered, however, and that impacts on the rest of the car. With no track testing available some teams may take time to hone their new packages.

“We were disappointed, that’s for sure, because we and six other teams had a different view of the regulations, especially the intention of the regulations,” BMW’s Mario Theissen told Motor Sport. “Obviously it is a big handicap for this season. We have to rush to develop our own solution, which is quite difficult without any in-season testing. The teams who have it already will develop as well.

“We have to assume the full potential of such a solution has not been exploited yet, not by far. It will carry on throughout the season. It is definitely much more than just changing the diffuser. The airflow of the diffuser is affected by anything upstream, so we have to redesign the whole aero package.”

The situation is complicated for some teams by the layout of their gearbox and rear suspension. McLaren and its gearbox customer Force India are believed to have the easiest task and do not need to make major mechanical changes, while Red Bull is at the other extreme. An added complication is that any design changes to a gearbox and suspension mountings will have to dovetail with the four-race cycle, or drivers will face a five-place grid penalty for taking a new unit. Ferrari meanwhile has a specific problem with the location of its hydraulic system.

RBR team boss Christian Horner told Motor Sport: “We’re now faced with having to go and design our own solution, and for an independent team such as ourselves there’s a massive amount of cost involved. It’s significant because it is such an integral part of the car, and it’s not just a bolt-on solution.

“So there’s a huge amount of redesign work that needs to go into the back of the car. Certainly the suspension will need to be different. It’s almost a B-spec car, so it’s a massive commitment. Hopefully we can look forward to [improving] performance with a double diffuser on a car that’s already pretty competitive.”

Most other teams are expected to introduce several versions of the diffuser as they make those mechanical changes and begin to get full value from the new arrangement.

“Obviously Spain is a real focus for a decent package as it will be for many of the teams,” said McLaren’s Martin Whitmarsh. “We have double diffusers in our wind tunnel, and from the very first moment we put one in, we found a performance advantage. Clearly you can increase that advantage by optimising the package.

“One of the tough dilemmas that most teams are facing is to what extent do you now start to redesign the rear suspension, the back of the car, the transmission, to actually optimise for this particular philosophy. If you choose to do that you’ll be a good way through the race season before you are going to see those benefits. Meanwhile can you get 80 per cent of the potential benefit of this concept within your existing packaging constraints?

“That’s the trade-off we are doing. The gains are sufficient that I expect we shall see different forms of double diffuser on nearly all the cars in Spain, and for those of us who are late to the game we will see further steps as we’re obliged to freeze design and implement, because there is a reasonable performance opportunity there.”

Whitmarsh was keen to point out that Mercedes customer Brawn would still be at the front of the field, even if the double diffusers had been outlawed.

“One thing we should say about Brawn is they are not being successful at the moment merely because of a double diffuser. They have put a tremendous amount of effort and resource into developing this year’s car.

“It’s often the case that if a car is particularly quick we like to focus in on one idea, one concept, but it’s seldom the case. Had the Court of Appeal gone the other way then we wouldn’t have seen Brawn disappearing backwards.”

The story behind Brawn’s success, p88