Visualising the technical rules: 2017/2018 front wing dimensions

F1Technical has done such articles in the past, where we try to bring line after line of regulation into an easier to understand visual concept. To check front wing regulations of the previous era, we'd like to recommend our article on this: https://www.f1technical.net/features/11634. Regulations on the front wing did already change in 2014, but only in terms of length of certain regulation boxes, with the approach being otherwise completely the same as the 2009 regulations. That's the reason why we did not cover it as extensively back then.

For 2017 however, the regulations in this area, as well as other areas, have been completely rewritten. Not only to adapt to the intended swepped back front wing profile, but also to simplify regulation as the technical rule book has grown massively over the years. going from 2 sheets of paper in the 50's/60's to a full 105 pages in the current form. There's little to nothing to be found in the media about this simplification, so we'll cover that as well.

The most recent F1 technical regulations, at the time of writing, can be found at https://www.fia.com/file/64927/download ... n=XN2hTEj2

Front wing sections

The front wing is a complex aerodynamic component of the car, and through the years, regulations have become more complex as well to reduce the liberty of the designers. Most specifications are written in 'Article 3. Bodywork And Dimensions' of Formula One's technical regulations. These are supplemented by several appendices, using drawing to avoid any misunderstanding or liberal "interpretation of the rules".

Throughout the entire regulations, there are 3 terms that are important to determine the position of an item in 3 dimensional space:

• Reference plane: a horizontal plane that coincides with the plank of the car. It is essentially a plane defined by the X and Z axes versus which heights are specified along the Y-axis. The exact description of it can be found in 3.7.1
• Wheel centre line (front/rear): used to determine length. The 0 position is at the centre of the wheel. The exact description can be found in 3.1.1
• Car centre line/plane: used to determine width. It's measured for the survival cell being split into 2 symmetrical pieces. The exact description can be found in 3.1.3 and Appendix 1. Drawings, Drawing 5.

In order to better visualize it, let's take a current front wing as an example:

Bounding box

Article 3.3.1 defines the overall box that contains the front wing elements. It's this article that was changed ahead of the 2017 season to make sure that front wings are swept backwards by 12.5° to a better 'look' (specified via the diagonal lines set by 3.3.1.a and 3.3.1.c).

Fixed central section

Not part of article 3.3.1 is the 250mm wide central section of the front wing. This is outlined in article 3.3.2, which was added as part of the aerodynamic regulation changes of 2009.

Which is the part of the wing coloured yellow:

But what do the regulations mean regarding this piece? If we take the neutral section and slice it along any line parallel to the car centre line, the cross section in side view will always be the same no matter which line you slice it, meaning the profile in side view has to be the same along the entire width of this section. The sole exception being very small alterations to fit the front wing pylons. The intention of this is to create a downforce neutral profile, although teams still manage to extract downforce from this profile in a number of ways.

So this means the cross sectional profile itself is standarized. Exact details can be found in Appendix 1 Drawings, 'Drawing 7', which very specifically gives a table of coordinates for the edge of the cross sectional profile. It essentially specifies the exact location and dimension of this section relative to the car's reference plane. The only way teams can actually change its position relative to the ground is by tilting the car, which is one of the reasons why modern cars are set up with high rake. This is one way to still extract downforce from it.

The teams neither have much of a way to differentiate with the profile in bird view, as it has to follow a certain curve. Although the curve itself is quite loosely defined, the chord length is already defined through the profile coordinates, meaning it can't go wider or thinner across it's length.

These same rules are also the reason why the neutral section does not end in a point as shown in almost every illustration before 2017, but in a rounded off tip. This is probably done out of safety concerns.

Exclusion zone

Another limitation, also introduced in 2009, is an exclusion zone for any kind of bodywork:

This results in an exclusion zone inside our box, represented in red:

As one can notice, the above rules cut inside our box for regulated bodywork as well, reducing area for the wing elements or other bodywork. This regulation thus simultaneously reduces effective flap surface AND pretty much locks the neutral section's position.

This concludes the effective area for front wing body work. However, there is still a specific type of bodywork the teams have to apply: 'the endplate', section 3.3.4 in the rulebook.

This means the endplate has to be housed in the blue area. However, the positioning of the endplate is very predictable, with the leading edge as much forwards as possible, as well as the entire plate as far outboard as possible. This is done to maximize aero performance.

Further note that regulations prescribe that the endplate needs to have a surface 95,000mm² in side view, with the effective maximum surface in that area being 110,000mm². The way this has to be looked at, is that the teams have 15,000mm² (in side view) of open area to play around with. And this really is where teams differentiate with solutions, although this open area is almost exclusively being applied at the back of the endplate.

Interestingly, there are suspicions that if this regulation was not present, teams would not place this piece of bodywork. This might sound contradictory to the dozens of studies regarding the positive effects of endplates on wings. The answer is actually simple: the piece that is called an "endplate" in popular jargon and indeed in the regulations itself, is not really an endplate! It's a vertical fence that in reality acts more as a blockage to how the teams want to steer airflow outboard. The part that comes close to being an actual endplate, function wise, are the series of outboard elements, marked in green:

Note the current front wings have a lot of the same characteristics as diffusers have, because they are very dependent on ground effect. Hence why the mandatory fence does not work.

So what are the simplifications?

Before 2017 we actually had rules that demanded footplates, shown in the area highlighted in purple (positioned adjusted to 2017 front wing):

The rules of 2016 mention this:

It's guessing why they removed this rule, but given teams still apply the footplate in this area in the same way as they did before, means that the previous regulations were not any hindrance at all on the optimum design for this section in particular. Teams would use the footplate anyhow because it effectively enhances ground effect and seals off the underside of the wing elements. Based on that, one might say they got rid of the rule purely because it was redundant. We are yet to see any design that makes use of the removal of this section.

A second simplification is that they got rid of the maximum surface area on the inboard sections of the wing elements, close to the neutral section. It was oulined in the 2016 technical regulations in article 3.7.4 as follows:

This same regulation also prescribed the area where bodywork would be allowed, but as mentioned above, this is now also covered by the bodywork exclusion zones.

The old 3.7.4 paragraph translates into the below orange section, with red being the current bodywork exclusion zone.

It is likely that, throughout the years, it became clear that the teams did not even get to the maximum 20,000mm². A reason why is because the trailing edge of the wing is a vital part as it determines the quality of air the aero devices further back receive, especially the splitter. If the trailing edge was introduced to abrupt direction changes, this could send air and/or vortices in an unwanted direction and rob the car from downforce. Since the teams have to taper this trailing edge to the neutral section anyhow, to create the Y250 vortex, and have to avoid stepping outside the prescribed area for bodywork (2016) or stepping inside the exclusion zone (2017), this zone is not likely to reach a surface beyond 20,000mm².