As with all matters Formula One,
Geezer it is not quite so straightforward.
The new rules are too lengthy to go into here in detail. However, cars have always had diffusers, but the rule changes this year drastically restrict the size allowed. To get round this, the three �rogue� teams (Brawn, Williams and Toyota) have include in their diffuser apparatus parts of the bodywork not otherwise used for that purpose. Brawn say the �extra� diffuser area they are using is not part of the diffuser itself, but simply a part of the bodywork. The current dispute centres on the �reference plane� from which the size and location of the diffuser must be measured. As I said, too complex to go into here. This might help:
http://www.autosport.com/news/report.php/id/73 083
In previous years, it would have been no big deal. The other teams would simply have modified their cars in the same way and would only have been disadvantaged for a race or two. This year it is different. No in-season testing is allowed for development purposes so any modifications would have to be tested at the race weekends.
Ferrari and McLaren fell a bit behind the smaller teams in developing their 2009 car last year because they concentrated their efforts on 2008. The smaller teams, and in particular Honda (now Brawn) virtually gave up on 2008 because they knew the drastic rule changes for this year would necessitate a complete re-design of their car. Accordingly they threw their efforts into 2009.
The FIA knew of this row long before the season started, and the three teams were given the all clear on their diffuser design. The scrutineers at the first two races passed the cars to race.
I�m hoping that the appeal is simply posturing by the bigger teams who have been caught out this year when they cannot easily catch up. I