Motor racing's governing body has moved to bring an end to renewed concerns about flexi-wings in Formula One by implementing immediate changes to the rear wing regulations, autosport.com can reveal.
FIA technical delegate Charlie Whiting has written to the teams advising them that, from the Canadian Grand Prix, slot-gap separators will have to be added to their rear wings in a bid to ensure that no teams' wings can flex at high speed.
The controversy surrounding flexi-wings in the sport appeared to have died down after Ferrari, McLaren and BMW were asked to make revisions to their design after the Malaysian Grand Prix - when a number of teams had threatened to protest Michael Schumacher's car.
However, continued strong straight line performance from Ferrari, allied to dramatic improvements to speed from BMW-Sauber, led to renewed suspicions within the paddock that some teams were continuing to make use of some flexibility in their wings. There were no suggestions that the teams were breaking the regulations though.
The key area of exploitation was in designing the wings in such a way that the slot-gap between the two elements of the rear wing closed up at high speed, thereby reducing drag and increasing straight line speed. The slot gap would then open up at lower speed to ensure the wing delivered maximum downforce through the corners.
There are also suggestions that above a certain speed some teams have managed to get their aero package to stall - which leaves them with zero drag.
With the forthcoming Montreal and Indianapolis circuits being ideal venues for making best use of flexi-wings, because of their long straights and relatively slow corners, action has now been taken to try and alleviate concerns about the situation.
The teams have been asked to fit a central slot-gap separator to their cars from the Montreal race to ensure the two wings remain 50mm apart. These will ensure that there is no chance of them exploiting the regulations as the separator material will stop the elements of the wing flexing and therefore prevent teams from closing up the slot gap.
Williams technical director Sam Michael said: "The teams will have to have a slot gap separator so the slot gap cannot close.
"The wording of the directive is that no part of the wing can be more than 250mm laterally away from the support. So you can have a separator to stop it or you can have a snubber so that the support does not move."
The issue of flexi-wings has been discussed at length by F1 think tank the Technical Working Group, which recently approved a proposal for the slot gap separators to be introduced in 2007. Those plans have now been brought forward for immediate implementation.
Although it is hoped that the introduction of slot-gap separators will bring an end to suspicions about rear wings, it is unlikely to quell all talk about flexible parts.
"Everything flexes on a car," said one leading source. "The front wings flex, the winglets flex, most car parts flex. The issue is just likely to move on to somewhere else now."