McLaren and Mercedes GP have asked the FIA for clarification about flexible front wings in Formula 1, amid continued suspicions that Red Bull Racing and Ferrari are doing something clever with their designs to improve car performance.
Although the FIA gave the front wings of the Red Bull and Ferrari cars the all-clear after the German Grand Prix, rival outfits still suspect that the two teams have concepts to help lower the front wings, and especially the endplates, closer to the ground.
This has been further fueled by close-up video footage broadcast by Formula One Management over the Hungarian GP weekend indicating the front wings of the Red Bull and Ferrari cars are running much closer to the ground than other machines.
Rival outfits do not have a firm answer for exactly what the two pace-setting teams are doing, and the FIA has found nothing wrong with the cars. However, attention is now shifting to a cleverly designed floor area that could help allow the wing to lower at high speed - rather than the key to the matter being simply flexible endplates.
Mercedes GP team principal Ross Brawn said he and McLaren had approached the FIA because they wanted confirmation that they were allowed to pursue such clever innovation themselves.
Without that approval, there was a risk of them engaging on an expensive development program on such a wing system only for the FIA to outlaw it at a later date.
When asked by AUTOSPORT about the situation, Brawn said: "We know the whole area of stiffness is difficult and tests are devised to ensure that we are all in the same region.
"I think observation on the videos and stills show that Red Bull is the prime case, but Ferrari partially, has managed to set their cars up to run the front wings a lot lower to the ground than perhaps ourselves or McLaren have been able to achieve.
"I think probably what we are asking is, before we all go off and have a massive development program, is Charlie [Whiting, FIA race director] going to change the rules before we get there?
"When it is demonstrated to you, you look at all the ways that you can achieve it and I think for the latter part of this year, and next year, we will all be doing the same. We just want to make sure that Charlie is comfortable with it and is not going to change the rules when we get there, because it will be an awful waste of effort."
McLaren team principal Martin Whitmarsh ruled out the possibility of his outfit protesting Red Bull Racing or Ferrari over the matter, but is clearly unhappy with what his rivals are doing.
"Flexi wings - do I think they are right in F1 to be flexing to that extent? No I don't," he said. "But I am not the rule maker or the rule interpreter, so I think we are asking for clarification on what is permissible here.
"Once we have that clarification, then we are able to push to do whatever seems to be allowed. I hope the clarification really does not allow the endplates to continue to touch the ground. There are endplates out there whose metallic skids are touching the ground, which are meant to be way off the ground."
Whitmarsh believes that if teams were able to exploit the area of front wing design, and get the endplates lower to the ground, then there would be a considerable performance benefit.
"Clearly no wing can be infinitely rigid, but there are limits to which they should be allowed to flex," he said. "If you try to explain what is happening, either you can explain it by hugely raked cars - but if you do simple geometry then the ride height would be over 100mm and there is no evidence of that being the case.
"Or you do it by some means of the outer edge of the wings lowering down by more than we expect. Or the front of the floor is moving up further than we expect, because that is another part of bodywork that is intended to be rigidly attached.
"In truth we don't understand it and maybe there is another way but I, as a fairly simple engineer, can't think of anything other than those three explanations. If there is another one then I will be happy to hear it. It is surprising.
"I think the FIA has got to take a view now of what is acceptable, and if it is acceptable, to get the endplates down. Every millimeter is about one point of downforce at the front, although it also improves the rear. So 25-30mm of vertical lowering of the endplates is one second [per lap], so it is fairly substantial."
Whitmarsh said that if his team had known at the beginning of the year just how flexible it would be allowed to run its wings then it would have pursued that area of car design.
"Bodywork is required to be rigid, but the truth is all bodywork moves. Our wing moves. But our wing is moving relatively a small fraction in comparison and there is a continuum. We believe that the extent to which our bodywork is flexing is permissible. If we believed at the beginning of the year that such gross movement of the bodywork was permissible we would have done that.
"Progressively we have seen some teams' bodywork has become much more flexible - but maybe they are right, maybe they have got the right interpretation, maybe we have to be hard on ourselves that we have not been as brave, as creative or as diligent in this area as some of these teams.
"If anyone who just looks at the regulation 3.15 [of F1's technical rules], which says bodywork must be attached rigidly, then goes to look at endplates that ought to be 90mm off the ground and sees them touching the ground, then I think a lay person would be surprised that that is permissible."
Both Red Bull Racing and Ferrari have denied any suggestion they are doing anything wrong, and have repeated several times that their cars have passed all FIA scrutineering checks.