Rear wing flex and FIA regulatory test 2021

[cooken]

Exactly this!

What was meant was: what if you double the load, and get 2.01x the deflection? Is that ok? What about 2.05? 2.1? Remember this is real life and physical tests will never show a perfectly straight line. Linearity is a silly assumption we all learned in school to make things easy, and it's good enough for only very simple problems. The real world is always nonlinear (recall engineering stress vs true stress for example).

One can carry out the test several times. Plot the results of deflection v force applied. If it hockey sticks at a certain point but is still responding elastically then that's a design that's been created to give a moveable aero benefit without being caught by the current single load test.

I think the concern still remains, you have to quantify the kink. Again from physical test data there will be multiple kinks which could be smoothed in many different ways (eg regression). I agree a clear bifurcation would be difficult for a team to explain away, but you have to somehow define what that constitutes which is obviously tricky. Devil is in the details as it were.

PS: As Canadian I appreciate your hockey stick analogy, nice.

[El Scorchio]

More than half of this thread has been nothing but a repetition of the same exact talking points, really.

Yup, and largely an exercise in subjectivity and tribalism. I suspect several people would have a completely different opinion on this matter if it were the MB wing flexing and RBR complaining.

[RZS10]

"if it were the MB wing flexing *more relative to the others*" they all do a little bit of flexi action afterall

[El Scorchio]

"if it were the MB wing flexing *more relative to the others*" they all do a little bit of flexi action afterall

Ha! Yup, that'll do
Same sentiment though

[SiLo]

Just force the teams to run a thin cable from the roll hoop crash structure along to the DRS actuator housing. Heck, make it a standard part. Sorted.

[dans79]

Linearity is dead easy to show. You double the force applied and you get a consequent doubling of deflection. So long as you stay within the elastic limits of the material/structure, you can reverse the process and repeat it. If, however, increasing the force applied leads to a non-straight line graph of force v deflection, then you have something other than linearity. That in itself would point to a designed response and thus show intent.

Exactly this!

Plus minus tolerances of course. Which is half my point...

The other half is what does intent have to do with anything? It's a speeding fine (or not), not a murder trial.

At least that's my contention, please explain where intent is assessed in such matters, either through precedent or explicit regualatory text - I haven't seen it explained so far.

Intent is what matters, with regards to the wings flexing! As has been said several times everybody's Wing is going to flex to some amount.

Regardless of what the current or future tests are, if you have done something with the intent of passing the test but gaining an aerodynamic advantage in some way, then you are violating the spirit of the rules.

As was shown in Abu Dhabi 2014 even if you pass a given test you can still be found in violation of the rules because of intent.

The way of proving intent in this case, would be that after some threshold, the wing will show a nonlinear response to force applied to it.

A nonlinear response, would be proof of intent because, that is not what would happen if a component was designed to pass the tests, and not try and gain an aerodynamic advantage.

[nzjrs]

Exactly this!

Plus minus tolerances of course. Which is half my point...

The other half is what does intent have to do with anything? It's a speeding fine (or not), not a murder trial.

At least that's my contention, please explain where intent is assessed in such matters, either through precedent or explicit regualatory text - I haven't seen it explained so far.

Intent is what matters, with regards to the wings flexing! As has been said several times everybody's Wing is going to flex to some amount.

Regardless of what the current or future tests are, if you have done something with the intent of passing the test but gaining an aerodynamic advantage in some way, then you are violating the spirit of the rules.

As was shown in Abu Dhabi 2014 even if you pass a given test you can still be found in violation of the rules because of intent.

The way of proving intent in this case, would be that after some threshold, the wing will show a nonlinear response to force applied to it.

A nonlinear response, would be proof of intent because, that is not what would happen if a component was designed to pass the tests, and not try and gain an aerodynamic advantage.

I understand you think intent matters, I just don't think you have justification to think that. It's not clear to me from either precident or from the text that intent is required or not.

It's speeding vs murder. The relevance of Intent depends on the statute.

Can you point to something concrete where this intent point is clarified?

I'm not even disagreeing with you about the intent point, I'm just agnostic until I see evidence that intent matters generally and in this type of rule specifically.

[Tommy Cookers]

'linearity' - and 'non-linearity' as has been waved around in this thread ? .....

nothing mechanical is 'linear' .....
carbon fibre isn't
epoxy resin isn't

majorly 'non-linear' elastic elements in widespread vehicular use for 70 years .....
diaphragm springs
disc springs
pressurised sealing rings


I designed and made such 'non-linear' elements (to the requirements of large scale model tests for oil rigs) using ....
multiple hollow rubber springs - that progressively collapsed in succession as load increased above a threshold level

[RZS10]

Tell that to the FIA who uses said term in their very own rules. They specifically mention non-linearity.

Can you point to something concrete where this intent point is clarified?

You will not find the term written out in any rule or statement in previous cases but it's implied, isn't it?

The entire 2014 case hinged on whether the flexing was "built in" and the literal quote in 2014 was that the wing was "designed to flex under aerodynamic load".

"Designed to flex" = "intentionally flexing" = intent.

That was what mattered back then, what more in terms of evidence do you need? Unless you want to argue semantics.

[nzjrs]

Tell that to the FIA who uses said term in their very own rules. They specifically mention non-linearity.

Can you point to something concrete where this intent point is clarified?

You will not find the term written out in any rule or statement in previous cases but it's implied, isn't it?

The entire 2014 case hinged on whether the flexing was "built in" and the literal quote in 2014 was that the wing was "designed to flex under aerodynamic load".

"Designed to flex" = "intentionally flexing" = intent.

That was what mattered back then, what more in terms of evidence do you need? Unless you want to argue semantics.

I thought we were all arguing semantics?

[dans79]

I understand you think intent matters, I just don't think you have justification to think that. It's not clear to me from either precident or from the text that intent is required or not.

It's speeding vs murder. The relevance of Intent depends on the statute.

Can you point to something concrete where this intent point is clarified?

I'm not even disagreeing with you about the intent point, I'm just agnostic until I see evidence that intent matters generally and in this type of rule specifically.

here are all the documents from Abu Dhabi 2014.
viewtopic.php?p=971148#p971148

This is from the the technical delegates report.
https://www.fia.com/sites/default/files ... -%2028.pdf

When checking the front wing of car numbers 01 and 03 it was found that the front wing flaps were
designed to flex under aerodynamic load. In my opinion this is not in compliance with Article 3.15 of
the Formula One Technical Regulations. Therefore I am referring this matter to the stewards for their
consideration.

Designing something to work a certain way is intent.


here is a copy of the 2014 regulations.
https://argent.fia.com/web/fia-public.n ... _20.07.pdf

3.15 is what 3.8 is today.

[nzjrs]

I understand you think intent matters, I just don't think you have justification to think that. It's not clear to me from either precident or from the text that intent is required or not.

It's speeding vs murder. The relevance of Intent depends on the statute.

Can you point to something concrete where this intent point is clarified?

I'm not even disagreeing with you about the intent point, I'm just agnostic until I see evidence that intent matters generally and in this type of rule specifically.

here are all the documents from Abu Dhabi 2014.
viewtopic.php?p=971148#p971148

This is from the the technical delegates report.
https://www.fia.com/sites/default/files ... -%2028.pdf

When checking the front wing of car numbers 01 and 03 it was found that the front wing flaps were
designed to flex under aerodynamic load. In my opinion this is not in compliance with Article 3.15 of
the Formula One Technical Regulations. Therefore I am referring this matter to the stewards for their
consideration.

Designing something to work a certain way is intent.


here is a copy of the 2014 regulations.
https://argent.fia.com/web/fia-public.n ... _20.07.pdf

3.15 is what 3.8 is today.

Thanks!

[RZS10]

Yep, thanks mate ... i mean ... it's quite clear what the enforcement of the rules is based on and in the end it doesn't matter what you call it.

[dans79]

'linearity' - and 'non-linearity' as has been waved around in this thread ? .....

nothing mechanical is 'linear' .....
carbon fibre isn't
epoxy resin isn't

Perfectly linear no, but the FIA isn't looking for perfection.

They want to see something like this. For all intensive, linear all the way till you reach structural failure.

graph pulled from this paper
https://www.researchgate.net/figure/Loa ... _322215740


If fitted with a line, both of these would have a good correlation coefficient, and/or coefficient of determination, depending on what you chose to show accuracy of the fit. It only starts to fall aways as you approach the point of structural failure.

[DChemTech]

'linearity' - and 'non-linearity' as has been waved around in this thread ? .....

nothing mechanical is 'linear' .....
carbon fibre isn't
epoxy resin isn't

Perfectly linear no, but the FIA isn't looking for perfection.

They want to see something like this. For all intensive, linear all the way till you reach structural failure.
https://www.researchgate.net/publicatio ... cimens.png
graph pulled from this paper
https://www.researchgate.net/figure/Loa ... _322215740


If fitted with a line, both of these would have a good correlation coefficient, and/or coefficient of determination, depending on what you chose to show accuracy of the fit. It only starts to fall aways as you approach the point of structural failure.

Well, if that is what FIA wants to see, why don't they just add that to the rules? 3.9.9.2 "In addition to the test criteria above, the relation between deflection and load should under no non-fatal conditions exceed linearity" (or something along those lines, perhaps allowing for some -clearly defined- tolerance wrt linearity)

Or (for this example) "under no circumstance that does not compromise wing integrity can the deformation be more than [20 mm]". That was not in the original regs, but it hasn't been added to the new directive either - hence still leaving the prospective gray area wide open.