Ferrari SF-25

[Farnborough]

So the gearbox casing (structural member of the car) cannot take torsional loads if the suspension is stiff ?
How did this happen ? revised packaging given the 'shorter gearbox casing' requirement. Where did that requirement come from ?
'driver needs to sit more rearwards'.

I am sure the customer teams - Hass/Sauber uses their own gearbox casing design or are using SF-24's version. How can a top tier 'factory team' like Ferrari with state of the art tech and facilities at their disposal, get something like 'mechanical structure' wrong ? It's too basic a mistake. As a fan, I am boiling over, what must Elkkaan be feeling ? This is utter nonsense.

A reasonable assessment. Its not absolutely clear (whether they'll publish more in depth explanation IF they get a fix will be interesting) what they now view as under performance in detail of what is really happening.

Shorter structure SHOULD in ordinary practice give a better structural performance, and I'd discount that in logical reasoning.

The loads have been increasing substantially from step into 2022 season design. Whether they've truly enacted a reliable solution in this era would have to be considered. It's generally been a patchy and up/down performance overall for them. There was clear evidence of existence in this direction at COTA with plank wear exclusion in previous chassis. I don't feel the change to this year is entirely isolated.

This is one of the core area of a TD by laying out the hard performance "describers" putting trust in the factory decisions responsible, ultimately to "coach" them into the correct performance zone.

There's obviously huge pressure to reduce weight, to compromise in fitting component and it's relative performance within strict aero driven scheme.
Knowing the dominant attribute, to be preserved at all,cost, which may bring necessary compromise in another part of design is one that really defines a good TD .

Hopefully they know here exactly where they've currently missed their target, to then implement a step change.

The aero platform looks good, tentatively offering a glimpse of true performance when the track punishes the dynamic shortcomings less.
It could be a big step for them.

[Vanja #66]

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading. That being just basic mechanical principle, but effectively losing control of system performance by doing so.

Compliance in suspension system by virtue of poor torsional and bending stiffness of structural (sub)frame is one of the oldest problems of racing cars. I'm pretty sure the understanding of it pre-dates F1 itself

From what I've been told, GB casing sizing is done based on deflection criteria, not stress criteria - precisely to prevent compliance. Let's not fall victims to Occam's razor

[organic]

Ferrari in Monaco config


Max DWF rear-wing

Giuliano Duchessa

[vorticism]

How can a top tier 'factory team' like Ferrari with state of the art tech and facilities at their disposal, get something like 'mechanical structure' wrong ?

Same way the Merc F1 brain trust arrived to the conclusion that it would be good to introduce a car with no sidepods in a formula that demanded wide sidepods. The galaxy-brains later blamed it on their wind tunnel techs--perhaps fitting for what was of course and unquestionably the most morally virtuous F1 team to ever grace the paddock, as they were often want to remind the heathens and gammons in the stands.

"Driver needs to sit more rearward" if so that'll be another RB18 series adoption for the red Red Bull, although we're heading into a new formula next year, so it's a moot point.

[Farnborough]

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading. That being just basic mechanical principle, but effectively losing control of system performance by doing so.

Compliance in suspension system by virtue of poor torsional and bending stiffness of structural (sub)frame is one of the oldest problems of racing cars. I'm pretty sure the understanding of it pre-dates F1 itself

From what I've been told, GB casing sizing is done based on deflection criteria, not stress criteria - precisely to prevent compliance. Let's not fall victims to Occam's razor

And so, on the simplest basis, they've either missed their target in design, failed to appreciate in setting a viable target initially, or failed to build the structure that meets the target asked for.

All of them a failure of technical direction, however so they've arrived at this analysis from trying to accommodate by adjustment on track.

Yes I'm perfectly aware of structural compromise in vehicle chassis design .... ordinarily they are named "flexi-flyers" colloquially snd by those working with them.

[Vanja #66]

And so, on the simplest basis, they've either missed their target in design, failed to appreciate in setting a viable target initially, or failed to build the structure that meets the target asked for.

All of them a failure of technical direction, however so they've arrived at this analysis from trying to accommodate by adjustment on track.

Yes I'm perfectly aware of structural compromise in vehicle chassis design .... ordinarily they are named "flexi-flyers" colloquially snd by those working with them.

The casing structure is not the issue and never was

The issue was with the mechanics inside - suspension collapsed and cascaded when car was set as low as intended by design, not the casing itself

[Farnborough]

And so, on the simplest basis, they've either missed their target in design, failed to appreciate in setting a viable target initially, or failed to build the structure that meets the target asked for.

All of them a failure of technical direction, however so they've arrived at this analysis from trying to accommodate by adjustment on track.

Yes I'm perfectly aware of structural compromise in vehicle chassis design .... ordinarily they are named "flexi-flyers" colloquially snd by those working with them.

The casing structure is not the issue and never was

The issue was with the mechanics inside - suspension collapsed and cascaded when car was set as low as intended by design, not the casing itself

what do you mean by this description ? Which components are "collapsed and cascaded" ?

[Vanja #66]

what do you mean by this description ? Which components are "collapsed and cascaded" ?

My best guess is heave element issues - in practice it's softer than they need and they may not be able to increase the stiffness further because it would bring tyres in the wrong window or it's simply as stiff as it can be for the given diameter and/or volume. It might be just soft enough to yield a bit more than what is calculated and lower the car initially, but as the rear floor drops down the load starts increasing exponentially and the whole rear end cascades much lower than intended (so they raise the car by 3mm according to Hamilton) That's my theory

Multiple sources told me Ferrari don't have enough room to put in "big enough" elements. It may also be the case of mechanical compliance within rockers or other parts within the scope of current design.

In any case, only new mechanics and updated fairings on arms and rods will be brought, not the casing. They will try working around the problem and within the volume of current casing

[FDD]

what do you mean by this description ? Which components are "collapsed and cascaded" ?

My best guess is heave element issues - in practice it's softer than they need and they may not be able to increase the stiffness further because it would bring tyres in the wrong window or it's simply as stiff as it can be for the given diameter and/or volume. It might be just soft enough to yield a bit more than what is calculated and lower the car initially, but as the rear floor drops down the load starts increasing exponentially and the whole rear end cascades much lower than intended (so they raise the car by 3mm according to Hamilton) That's my theory

Multiple sources told me Ferrari don't have enough room to put in "big enough" elements. It may also be the case of mechanical compliance within rockers or other parts within the scope of current design.

In any case, only new mechanics and updated fairings on arms and rods will be brought, not the casing. They will try working around the problem and within the volume of current casing

Would be nice if they manage to solve this with moding the mech without new casing, cause AFAIK they need much more time to develop new casing including the crash test.
The issue about the suspension and its ability to handle the DF means that they have wrong model at the time of test in the simulator i.e. low correlation, opinion?

[Vanja #66]

The issue about the suspension and its ability to handle the DF means that they have wrong model at the time of test in the simulator i.e. low correlation, opinion?

Something happened which they didn't expect, probably poor understanding of the rear end limits. SF23 was bad, but they later admitted they knew this from the early sessions in simulator. This issue caught them by surprise in Australia

[leblanc]

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading.

Which structure? Just so I'm clear. The gearbox case or the chassis?

The rear "outer" structure holding the suspension components, not the gearbox holding the gears.

There's very good clue in this aspect given at Bahrain test. There was concern over gearbox "problem" at that point. But importantly there's been absolutely no record of gearset/transmission failure or otherwise changed (short service life) that we've seen so far this season. Its a projection, but one that indicates this component is not compromised by variance in it's local structure to raise or compromise tolerances within it's components.

That is specifically separated for load it seems from any effects they are sering in regard to suspension integrity.

I'm commenting from the structures I've observed first hand and NOT the record out in public space. The rear "structure" is effectively a carbon dominated monocoque as is the primary front driver monocowue construction. Taking all of the load from suspension, wing, floor etc, etc as core duty and not the "traditional" gearbox taking the drive from PU to drive shaft output. This is the contemporary design used and primary difference to units commonly in place before gearbox penalty was in place.
It's an important delineation .... as I've repeated a few times ... which allows the gearbox components controlled by that penalty system to be retained and fitted to a replacement "exoskeleton" in event of accident damage resulting in suspension pickup location failure through impact.

Thank you. Then this exoskeleton is outside (literally) of the enclosure that contains the cassette.

[f1isgood]

Courtesy of @f1sutton (Story) on Instagram. The SF-25 floor. The Link: https://www.instagram.com/stories/f1sut ... 909663378/

[Farnborough]

Good view, interesting strake arrangement at entrance area too.

For those that doubt plank wear near rear is ordinarily part of setup consideration, look how much "witness" evidence is there on this one !

Are the numbers on underside to identify pressure tappings ? That's what I'd assume for id and correlation.

[Lasssept]

@diegofmejia

[vorticism]

Ferrari S.p.A. ought to sell copies of that CV joint transport cover as a latte mug in their gift shop. Perfect shape/size.