Rule Interpretation - Double deck diffusers

[gcdugas]

Does anyone have any pics or know more about this story?

[Conceptual]

Did the Williams and the Toyota co-develop this area behind the engine?

If this is allowed, we are going to see a HUGE increase in what the teams have gotten back in terms of downforce. And if the other teams dont follow suit, they may end up behind these cars.

If the bodywork is done with the intention to re-couple the rear wing/diffusor, then I'm sure that it will be banned. If it is just creative bodywork in an area that is allowed to be developed, then I think it will be allowed.

Genius like this is what will make the 2009 cars faster than the 2008 cars.

Who thinks that by Abu Dabhi (last race) the 2009 cars will be back at 100% of 2008 downforce levels?

[Scotracer]

The diffuser regulations are really quite obscure for this year. Reading them you could interpret them a number of ways so no doubt teams will come up with vastly different solutions.

Personally that's a good thing

I'm not too sure about the statement "Will help in slow corners" as the diffuser only really helps at higher speeds.

[smirkoff]

I really like the rules to be always so open to different interpretations, but I'm always amazed that the FIA still insists in text descriptions; with the current technology, why don't provide 3D drawings of the rules concerning bodywork, safety and aerodynamic parts, showing clearly the limits? The drawings attached to the current regulations pdfs (at least the ones available at the FIA site) are incredibly poor and outdated.

[axle]

I really like the rules to be always so open to different interpretations, but I'm always amazed that the FIA still insists in text descriptions; with the current technology, why don't provide 3D drawings of the rules concerning bodywork, safety and aerodynamic parts, showing clearly the limits? The drawings attached to the current regulations pdfs (at least the ones available at the FIA site) are incredibly poor and outdated.

But surely if the FIA wanted to be that prescriptive they'd supply a diffuser as a standard part...

[NDR008]

I really like the rules to be always so open to different interpretations, but I'm always amazed that the FIA still insists in text descriptions; with the current technology, why don't provide 3D drawings of the rules concerning bodywork, safety and aerodynamic parts, showing clearly the limits? The drawings attached to the current regulations pdfs (at least the ones available at the FIA site) are incredibly poor and outdated.

The Toyota/DENSO (and most Japanese companies) actually try avoid words as much as possible for that reason. A diagram is more to the point really, then text can help iron out - fine tune an explaination.

Sometimes I wonder if the ambiguity is intentional to be able to penalise an over-successful team mid-season, to balance out things again and make the season dramatic.

[scarbs]

Yes its not such a drama as the magazine has made it (headline on front page "F1 tech crisis"). Williams and Toyota do have different diffusers, the everyone elses launch diffusers.
The Toyota makes use of the 15cm allowable area along the cars centreline. This was debated a lot on the 2009 regs thread. It's clearly legal and there's no issue there.
Williams have been alot more creaative, just as last years diffusers were mandated to 125mm high, many team still had extra diffusers channel far higher, as they sat above a 'false cieling' in the lower part of the diffuser.
What williams have done is take the 'bodywork facign the ground' fact literally, and creates a split level diffuser, the lower part is no higher than 175mm as per the rules, in fact in places its alot lower. but theres a secondary tunnel above this, clearly somewhere under the floor, where the stepped flat section ends and the diffuser starts, where there a window up into this upper section. This Williams have created more exit area around what the rules meant.
Is this legal? Sam Michael certainly told me it was, Pascal Vasselon knew about it, so I am inclined to think this is legal, but might see a clarification from the FIA.

Scarbs

[axle]

Scarbs,

How fast can the other teams react and copy should it be deemed legal? Ie Will Williams' "advantage" be voided before they get to Oz?

If so why would they show it off so early?

[scarbs]

Scarbs,

How fast can the other teams react and copy should it be deemed legal? Ie Will Williams' "advantage" be voided before they get to Oz?

If so why would they show it off so early?

I expect most teams already had Toyota's solution in hand. For most teams a major change to the diffuser concept (such as Williams doubel decker) will be a huge task, they might find developing their own solution may be a better medium term solution.
I cant explain why Williams went so soon with the diffuser, its tightly tied into the coke bottle shape so may be a conventional set up was not worth the effort.

[Ciro Pabón]

Thanks to Mafia, at GrandPrix forum. I'm not sure if that's it.

[axle]

Can anyone explain what is under review here? Just so as I'm 100% clear.

Thanks

[Conceptual]

I love it!

[donskar]

I really like the rules to be always so open to different interpretations, but I'm always amazed that the FIA still insists in text descriptions; with the current technology, why don't provide 3D drawings of the rules concerning bodywork, safety and aerodynamic parts, showing clearly the limits? The drawings attached to the current regulations pdfs (at least the ones available at the FIA site) are incredibly poor and outdated.

But wouldn't that require that the FIA have advanced technology, like computers?

[ESPImperium]

Picked up the mag today and its a pretty intresting article.

Areas in red are the disputed areas:

Williams FW31:



Toyota TF109:



To what the Renault R29 diffuser ls like:



And the McLaren MP4-34:



What the rules say:

3.5 Width behind the rear wheel centre line :
3.5.1 The width of bodywork behind the rear wheel centre line and less than 200mm above the reference plane must not exceed 1000mm.
3.5.2 The width of bodywork behind the rear wheel centre line and more than 200mm above the reference plane must not exceed 750mm.

3.12 Bodywork facing the ground :
3.12.1 All sprung parts of the car situated from 330mm behind the front wheel centre line to the rear wheel centre line, and which are visible from underneath, must form surfaces which lie on one of two parallel planes, the reference plane or the step plane. This does not apply to any parts of rear view mirrors which are visible, provided each of these areas does not exceed 12000mm² when projected to a horizontal plane above the car, or to any parts of the panels referred to in Article 15.4.7.
The step plane must be 50mm above the reference plane.
3.12.2 Additionally, the surface formed by all parts lying on the reference plane must :
- extend from a point lying 330mm behind the front wheel centre line to the centre line of the rear wheels;
- have minimum and maximum widths of 300mm and 500mm respectively ;
- be symmetrical about the centre line of the car ;
- have a 50mm radius (+/-2mm) on each front corner when viewed from directly beneath the car, this being applied after the surface has been defined.
3.12.3 The surface lying on the reference plane must be joined around its periphery to the surfaces lying on the step plane by a vertical transition. If there is no surface visible on the step plane vertically above any point around the periphery of the reference plane, this transition is not necessary.
3.12.4 The peripheries of the surfaces lying on the reference and step planes may be curved upwards with maximum radii of 25mm and 50mm respectively. Where the vertical transition meets the surfaces on the step plane a radius, no greater than 25mm, is permitted.
A radius in this context will be considered as an arc applied perpendicular to the periphery and tangential to both surfaces.
The surface lying on the reference plane, the surfaces lying on the step plane, the vertical transitions between them and any surfaces rearward of the surfaces lying on the reference or step planes, must first be fully defined before any radius can be applied or the skid block fitted. Any radius applied is still considered part of the relevant surface.
3.12.5 All parts lying on the reference and step planes, in addition to the transition between the two planes, must produce uniform, solid, hard, continuous, rigid (no degree of freedom in relation to the body/chassis unit), impervious surfaces under all circumstances.
Fully enclosed holes are permitted in the surfaces lying on the reference and step planes provided no part of the car is visible through them when viewed from directly below.
3.12.6 To help overcome any possible manufacturing problems, and not to permit any design which may contravene any part of these regulations, dimensional tolerances are permitted on bodywork situated between a point lying 330mm behind the front wheel centre line and the rear wheel centre line. A vertical tolerance of +/- 5mm is permissible across the surfaces lying on the reference and step planes and a horizontal tolerance of 5mm is permitted when assessing whether a surface is visible from beneath the car.
3.12.7 No bodywork which is visible from beneath the car and which lies between the rear wheel centre line and a point 350mm rearward of it may be more than 175mm above the reference plane. Any intersection of the surfaces in this area with a lateral or longitudinal vertical plane should form one continuous line which is visible from beneath the car. A single break in the surface is permitted solely to allow the minimum required access for the device referred to in Article 5.15.
Additionally, any bodywork in this area must produce uniform, solid, hard, continuous, rigid (no degree of freedom in relation to the body/chassis unit), impervious surfaces under all circumstances.
3.12.8 All sprung parts of the car situated behind the rear wheel centre line, which are visible from underneath and are more than 250mm from the centre line of the car, must be at least 50mm above the reference plane.

Basically it all revolves arround a maximum height of 175mm line, that the red sections are above and could provide a performance advantage.

I cant find a pic or the Ferarri or the BMW Sauber F1.09 diffusers.

[GTO]

I really like the rules to be always so open to different interpretations, but I'm always amazed that the FIA still insists in text descriptions; with the current technology, why don't provide 3D drawings of the rules concerning bodywork, safety and aerodynamic parts, showing clearly the limits? The drawings attached to the current regulations pdfs (at least the ones available at the FIA site) are incredibly poor and outdated.

Agree 100% with you Smirkoff. I work in the engineering field. We constantly refer to & must follow specific client standards. Attached at the end of their detailed written documents are drawing details that clarify their requirements. Obviously, the current FIA governing body has not thought of this idea or does not have sufficient funds to update their dwgs. Perhaps the new FIA president can address this as a future cost saving measure for the teams from wasting time & $$$ to re-work their designs due to lack of clarity in regulations.