Double diffusers ‘banned for 2011’

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F1 will ban double diffusers in 2011 according to Autosport.

The controversial diffusers were ruled legal after last year’s Chinese Grand Prix, forcing several teams to re-design their cars.

They allowed teams to claw back much of the downforce they had lost because of changes to the rules in 2009. They were also blamed for making it harder for drivers to overtake – though some designers have disputed that claim.

After first legalising the diffusers and then deciding they would be banned again in the space of just ten months, you have to wonder if they should have been made legal in the first place.

Double diffusers

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Keith Collantine
Lifelong motor sport fan Keith set up RaceFans in 2005 - when it was originally called F1 Fanatic. Having previously worked as a motoring...

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24 comments on “Double diffusers ‘banned for 2011’”

  1. WHY it is not banned for 2010?

    1. Prisoner Monkeys
      22nd January 2010, 12:03

      Because Bahrain is forty-odd days away. It’s too soon to force a change. After all, when Red Bull intrduced a double diffuser, it had to wait until Silverstone because it required a re-design of the entire rear-end.

    2. All the teams have developed their cars around it, it is way too late for them to have to re-design their cars.

      1. Oh, I don’t know though. A template and a pair of cutters could solve the issue very quickly. :)

  2. Keith, I disagree with your last sentence. The double-deck diffusers weren’t “made legal” ten months ago in a sense which would make this a U-turn; there was a loophole in the wording of the 2009 technical regulations, which was exploited by three teams. The FIA had no choice but to agree that the DDD was (already) legal under the rules.

    @wasiF1: FOTA talked in April about changing the rules for 2010, but then the budget cap and breakaway arguments started, and these took up everyone’s time. It then got far too late to change before 2011. It’s not worth getting frustrated about – the importance of this diffuser design in terms of speed and ability to follow another car has been greatly exaggerated in my opinion.

    1. i think the diffuser is one of the most important elements in an f1 car.
      its purpose is two-fold:
      1. accelerate the airflow under the car. this creates downforce not just at the rear, but over the entire floor.
      2. reduce drag by filling the space formerly occupied with car with air. the faster air fills this space, and the closer it is to its original condition, the more effective the drag reduction.

      these 2 functions are very complimentary, and an improvement for one means improvement for the other. this, i believe, is the reason why exhaust pipes cannot vent into the diffuser.

      the great thing about brawn’s 2009 design was a hole in the middle that force-fed even more air into the diffuser. the hole was supplied air by channels on the back of the sidepods, reducing drag on the rear tires.

      1. The diffuser is important (I’m not saying it isn’t, and your comments are accurate and valuable), but the DDD innovation was probably worth only three tenths, if that, over a well-developed single-deck diffuser. People who say it’s the only reason Brawn won the first few races, for example, are overestimating the benefit.

        Your second point is the more important – a 100% efficient diffuser would allow for perfect airflow recovery behind the car. There’d be less of a ‘tow’ effect in the slipstream, but the reason cars can’t follow each other closely is the turbulence and low pressure on the front wing of the following car through the corners. A more effective diffuser, such as a DDD, actually leaves a higher-pressure wake. Those who believe that banning the DDD would immediately increase overtaking in F1 are barking up the wrong tree.

        1. thanks, although “valuable” might be a stretch :D

      2. “these 2 functions are very complimentary, and an improvement for one means improvement for the other. this, i believe, is the reason why exhaust pipes cannot vent into the diffuser.”

        I think you’ll find they use to vent exhaust into the diffuser to create a ground effect, Newey was the daddy at doing it.

    2. Mouse_Nightshirt
      22nd January 2010, 14:17

      Very much agreed with the idea the diffusers weren’t “made legal”.

      They were always legal – if teams can utilise the rules in such a way as to gain an ultimately fair advantage, it is not breaking the rules.

      The question should instead be – why make them illegal?

      1. Why make them illegal? Because they made overtaking more difficult, which contravened the spirit (if not the letter) of the regulations.

  3. SiY speaks words of wisdom.

    In more it was the teams that stretched out the appeal on the “legal” decision made at the start of last season, and it was the teams that have taken until now to agree to make them “illegal” for next.

    The FIA are being constantly tarnished with a brush here that was not of their wielding. Some would say the FIA should not have had the “loophole” in the first place but again, long before the start of last season, the teams had a chance to close it and chose (greedily in my opinion) not to.

  4. R.I.P. innovation, go thirteen in a dozen racecars. It shouldn’t have been such a fuss. It didn’t say in the rules that its not legal to have a double-deck diffuser, so it was legal. And why they have to ban them now, what harm did they do? I wish they had just approved the budget cap (maybe higher than 45m) and relax the technical regulations. That’s what would’ve made f1 f1 again in my opinion.

  5. Are they also to taking the opportunity to tighten the rules to ban barge boards and those side pod aero pieces which the 2009 rules were supposed to get rid of as well?

  6. I think it wasn’t banned in 2009 because Ross Brawn’s cars had them. We all know the level of influence he possesses with the FIA and it was all a big scheme to get his car to the front and then sold to Mercedes GP. Maybe its a wild controversial theory, but I’m pretty convinced about it as I have seen Renault’s mass damper banned halfway through a season to give Ferrari its advantage back. And several controversial parts on the Ferrari allowed during Ross Brawn’s era.

  7. Best F1 news yet. Can’t wait for 2011 :P

    1. Shame about 2010 then :P

      1. People attach too much importance to the tow effect of the double diffuser, track design and other aero elements (front and rear wing) are more important. Unless there are going to be other design restrictions I can’t see this making any difference to 2011. BUT i don’t want to see a heavily regulated design formula where innovation is suffocated. The FOTA technical working group are very quiet perhaps they have some ideas.

  8. I hope the ban on double diffusers will even the teams up just a little bit, with the teams having less downforce. But even a world renowned designer, Adrian Newey, isn’t convinced that banning double diffusers will make more opportunities for overtaking. I guess we’ll see in 2011. Either way, teams are very innovative, and they will think of ways to find more downforce to make up for what they will lose with the double diffuser.

  9. everything these days is being banned, when will the fia realise they are making more pronlems than they are solving? f1 is being “overfixed” the propblem was it was never broken.

  10. This seems pointless. F1 should think more radically if they want to improve overtaking…

  11. I guess the real reason they’re being banned is the idea that less downforce = less cornering speed = greater braking distances. The reason it’ll fail is that this was the same reasoning behind grooved tyres, and they massively improved overtaking, didn’t they?

    It’s ironic that perhaps the least disruptive major aero component is the one being banned, as a scapegoat. I guess that’s F1 these days: image.

  12. I have to say I find all this disturbing.

    Part of the reason F1 is so expensive now (and I do say part, and only part) is that the teams have to redesign their cars every single season to fit the latest “this’ll fix it” rule change.

    Personally, I don’t think there should be half as many technical regulations on the cars design. Allow the designers to be innovative and original. Cut the fat out of the rules and just keep a core set, mainly safety related.

    My dream rulebook would not even have strict power and weight limits. It would have Power Input to Weight limits, plus maybe a range allowed for the weight. Taking this as an example, a team could produce a powerful heavy car or a smaller, lighter car. They could produce a more efficient engine which extracted more power from a given amount of fuel. Use alternative fuels even, heck lets go crazy, someone might even come up with a viable electric F1 car! :)

    The more restrictions are placed on F1, the less interesting it becomes, so I am becoming less of a fan year on year…

  13. [..] A little unrelated, but I absolutely liked this blog post [..]

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