The FIA will subject Formula 1 cars to tougher rear wing flexibility tests from this weekend’s Chinese Grand Prix.
The sport’s governing body previously announced it would impose a new test from the Spanish Grand Prix, round nine of the championship, which will be held in June. However after analysing data gathered at last weekend’s round in Melbourne, it has decided to impose another new test with immediate effect.The test it will apply in Shanghai will significantly reduce how much teams’ wings may flex under load. The current test involves placing a 75kg vertical load on either edge of the rear wing’s main plane. When under that load, wings must move by no more than 2mm.
Under the new test which will be applied from this weekend, that limit will be cut to 0.5mm. The FIA informed teams of the change earlier today. For this weekend’s race only, a tolerance of 0.25mm will be permitted.
The FIA noted that all cars were found in compliance with the current regulations when they were tested at the Australian Grand Prix.
FIA statement on rear wing tests
As has been previously communicated, between the end of the 2024 season and the start of the 2025 season, the FIA exercised the authority it is granted under Article 3.15.1 of the Technical Regulations to introduce either new or more challenging load-deflection tests for the front wing (from race nine, Spanish Grand Prix), the upper rear wing, and the beam rear wing. In addition, the FIA requested to the teams to use cameras in free practice sessions to monitor the on-track deformations exhibited by the cars during the Australian Grand Prix.
Having analysed footage from the rear wing deformations combined to [with] the static deflections measured inside the FIA garage in Melbourne, the FIA has concluded that sufficient grounds exist for a tougher test to be introduced from the forthcoming Chinese Grand Prix on the upper rear wing.
More specifically, Article 3.15.17, introduced in 2025, states that if 75kg of vertical load is applied on either extremity of the rear wing main plane, the distance between the main plane and the flap (also known as “slot gap”) must not vary by more than 2mm. From the forthcoming Grand Prix in Shanghai, this limit will be reduced to 0.5mm. Due to the short notice for Shanghai only a tolerance of 0.25mm will be added to this new limit.
The teams were informed of this revised test early [on] Monday 17th of March.
The FIA wishes to further confirm that during the Melbourne event all cars tested against the requirements of Article 3.15.17 and found to comply, therefore all cars raced in Melbourne were deemed to be legal.
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Kris
17th March 2025, 12:24
Changing the rules so close to the next event is a terrible idea.
If they were legal in Australia there’s no need to change things before the summer as planned.
Lapov Onor
17th March 2025, 12:59
Agreed, especially since anyone that needs to make a change will struggle to get an updated part to Shanghai in time!
BMW P85 V10
17th March 2025, 13:12
Teams where warned about the proposed outcome of the new rules, somehow they where able to evade a negative test while still bending the rules by using bending wings. I think it is a good idea that the FIA will end this ASAP.
David
17th March 2025, 13:20
So either the FIA were happy that all the cars would be compliant with the Round 9 rule and brought it forward to avoid any opportunity for exploitation.
Or they weren’t happy with the camera footage of cars that passed the 2mm test and brought it forward to catch teams out.
We’ll find out soon which scenario is the correct one.
anon
17th March 2025, 14:08
It’s not quite either of those things – the FIA will still be imposing additional tests in Spain on the front wings, but has decided to introduce stricter tests on the rear wings for this race onwards.
Osnola
17th March 2025, 18:18
Thats only part of the rukes.
They should have adapted the testing already to the new rule.
In fact several teams seem to be not compliant as far as the rear wing flex but will receive stricter testing in shanghai.
Typical fia. Illegal but not illegal enough .
Jere (@jerejj)
17th March 2025, 13:30
An unnecessarily hurried tweak within a short GP interval.
F1statsfan (@f1statsfan)
17th March 2025, 13:55
Given that certain teams have yet again outsmarted the FIA by designing their wings to pass the test but while racing do specifically what benefits them despite the FIA forbidding it – it is not surprising the FIA takes this action.
The FIA should be smarter and no rely on load tests but simply disqualify cars which in their view at any moment during the weekend show too much deflection/bending/movement that can’t be explained by unexpected occurrence like Kimi’s car sparking by running too low following damage to the car.
In other words various teams ran illegal cars in the spirit of the rules but were legal because they passed the official test. Little bit like the whole Diesel gate were car were cleaner in the NEDC/WLTP test than in real life.
The end effect will be pretty much nothing – similar to the flexible floor TD in 2022 or 2023 and pretty much all TD issues in recent years.
anon
17th March 2025, 14:17
Your criteria seems to be subjective though – what exactly is supposed to be too much deflection?
The point of the load test is that it is a purely subjective measurement that can have set criteria assigned to it and can objectively be measured with equipment that is readily available to the scrutineers in the pit lane.
Given the complaints about the FIA being too subjective in their decisions, you seem to want an approach that introduced more subjectivity into the process.
S Arkazam
17th March 2025, 14:24
Maybe rather than the static test, they should allow Jo Bauer to measure the gap with a tape measure during the race.
I’m sure they can develop some kind of safety harness for him and determine that he should spend an equal amount of laps on each car to keep it fair.
Greg
17th March 2025, 19:38
They could use on-board cameras
Osnola
17th March 2025, 18:21
They already set the max deflection on the results of several camera tests but seem unable to check it in static conditione.
So they are illegal as shown by the cameras but not in static testing. Nothing new and something fia should have adressed by now
Doggy
17th March 2025, 15:31
I agree with you F1stats. I does not matter if one is not compliant by a bit or a lot. The reality is that both are out of what is accepted.
Radoye
17th March 2025, 17:31
The issue here is that there has to be an objective criteria to measure (non)compliance with the rules, the FIA needs to be able to prove that rules have been broken before issuing a penalty. Otherwise there will be accusations of favoritism, why was team X penalized when team Y wasn’t and such, or some teams might even take to courts to challenge FIA for libel.
Bullfrog (@bullfrog)
17th March 2025, 14:46
Is “placing a 75kg vertical load on either edge” the technical term for standing on it?
BasCB (@bascb)
17th March 2025, 14:53
:-)
tielemst
17th March 2025, 14:57
Not for me, I’m afraid… :)
SteveP
17th March 2025, 15:00
Only if I lose a bit of weight :(
tielemst
17th March 2025, 14:59
McLaren benefit from having a flexi wing + McLaren are a few tenths clear of the field = Speed up the rules so we can have a closer championship.
FIA still bending rules to keep the show going and the market growing.
MichaelN
17th March 2025, 16:15
McLaren has been pulling this “definitely not illegal trick” for a long time now, going back at least to last year. I don’t recall if it was an issue in 2023. If anything, the FIA is way late with stamping this out.
anon
17th March 2025, 17:54
MichaelN, I don’t think that there are many, if any, teams in the field whose car isn’t pushing the regulations in at least some way, so I doubt anybody can really claim any sort of superiority in that regard.
What does seem to change is how that is interpreted – often in a way where a team is labelled as cheating if somebody wants them taken down, whereas it gets changed to being a clever interpretation of the rules when we want to see them succeed.
Alex
17th March 2025, 15:14
Although it is probably not the case, it seemed that FIA waited for the race results of the first round before changing the wing bending test to hurt specific teams aiming for closer performance among cars from 2nd round on.
Coventry Climax
17th March 2025, 15:18
By the nature of their design and function, wings deflect oncoming air (horizontal) into having a vertical component, in order to either generate either lift (aeroplanes) or downforce (racecars), both being vertical forces, at the cost of an amount of drag. Reducing the drag when the downforce isn’t needed (straights) results in higher topspeeds and/or less fuel consumption and less tyre wear:
F1; the pinnacle of motorsports yet environmentally aware – my behind.
Then for the FiA to just test wings on their flex in the vertical direction only is – to try and keep it decent – an ‘omission’.
If a wing and/or it’s mounts flex horizontally, which is easy to realise given F1 speeds of travel through air, that too alters the angle of the plane of the wing under load, and to a degree depending on both the flex of the design and the position of the pivot point. That is fully missed by testing vertical only.
The only real solution is to scrap these rules from the book altogether and let teams come up with the best they can come up with in wing design, flex and all.
The FiA should focus on a way to measure the amount of dirty (non laminar) air generated, then quantise and restrict that, such that team’s advantages aren’t designed specifically to (have the component to) create a disadvantage to the other teams.
As long as that doesn’t happen, all these flex rules and tests and TD’s and whatnots, are just like non waterproof bandaids on a rainy day out sailing. And the talks about it – oh well, you get the picture.
Maisch (@maisch)
17th March 2025, 16:23
I wish they just let flexi wings free, its a common thing to make stuff flexible with composites, and F1 teams could probably come up with really cool stuff. The design boxes could still limit the movement.
Grapmg
17th March 2025, 18:44
Good point. Is there a reason why they banned the flexibility of the wings? If all teams are allowed there is a level playing field so why not.
N
17th March 2025, 22:54
Because its an avenue teams will have to start spending a lot of money for something the viewing public wont get any benefit. Remember, the excuse for banning DAS when teams realised Merc had built and advantage into their car
Antony
18th March 2025, 1:57
I don’t think this argument is valid given we have a cost cap
Coventry Climax
18th March 2025, 11:04
I don’t think this is a valid argument as the public will benefit by getting to see what they’re actually there for to see: Cars racing at the top level and teams developing cars that they think achieves that.
Should bring different car filosophies with some cars doing better at some circuits, and others at others. Great.
Will get us see certain drivers prefer certain teams and vice versa, because of the match between driving style and car filosphy. Also great.
Especially compared to the drab ‘everything the same’ that F1 apparently is after these days, which frankly, makes it all very boring.
I’ll say it again: The FiA should focus on a way to measure, limit and test for the amount of dirty air that cars generate, with the filosophy ‘Do what you like, but don’t spoil it for the car behind’.
Frasier (@frasier)
18th March 2025, 7:53
@maisch allowing flexing + striving for minimum weight = unexpected failures. We’ve seen wings fall off in the past… safety issues.
Coventry Climax
18th March 2025, 11:12
By that reasoning all private cars should be prohibited: We’ve seen accidents occur in the past.
Wings fall of because of weak constructions. That’s about the easiest thing to test, in the entire automotive world, and I’m talking both pre- and in-season for motorsports.
Or, another approach, and one I’m sure the FiA will even prefer because they’re lazy and it’s simple: sanction teams heavily when cars shed parts. (Differentiated over circumstances, obviously.)
Riccard
17th March 2025, 18:06
This is an own goal for the FIA’s credibility.
Whatever the real chain of events, it makes it look like they saw McLaren’s performance advantage; possibly saw their wings bend on camera using those small dots placed on the cars; read the articles making them clear favourites for the championship; and got spooked.
It would have been much better to make this call at the start of the off-season, or at least before teams flew off for Australia, rather than expecting anyone non-compliant to ship an extra part out to China by Thursday.
They shouldn’t leave themselves open to the (natural) conclusion that they are trying to selectively enforce the rules to achieve close racing.
Osnola
17th March 2025, 18:23
Fia and credebility in one sentence…
Can not be right…
Riccard
17th March 2025, 18:46
It’s fine when the sentence also says “own goal”!!
SteveP
17th March 2025, 18:48
I feel your sentence may be a little lacking <<== ah there it is
Alesici
17th March 2025, 20:38
Did the FIA not consider the possibility that some teams will have brought a different design of wing more suited to the needs of the China circuit, or just more evolved design? That wing might be a bit more on the edge, such that they might not pass the tightened test, unlike those used in Australia? It seems pretty harsh to give them less than a week’s warning to stiffen those designs.
Doug Finley
18th March 2025, 4:23
150kg total isn’t that much, presumably limited by how much weight a scrutineer can lift. At high speeds, F1 wings produce more downforce than the 800kg weight of the car and driver, and the rear roughly 2/3 of it. I.e. they really could run upside down on the ceiling of a tunnel, if so arranged. So not to worry, they can still flex useful amounts at straightaway speeds.
Coventry Climax
18th March 2025, 11:17
You’re spoiling all the controversy and heated discussions by coming up with logic: Don’t ever do that again!
Mark (@mrcento)
18th March 2025, 5:42
Translation- After seeing a glimpse of McLarens pace in the once semi-clear and stable stint we got in that race, where they dropped the entire field to such an extent that even Max was losing the thick end of a second a lap, an analysing the data that pointed to a crushing 1-2 to a level not seen since the Mercedes early Hybrid era, for the sake of the show, we’ve got to see if that will rein them in a bit…..
MG1982 (@mg1982)
18th March 2025, 7:40
I guess you’re right, it’s intended to cut (part of) McLaren’s advantage. Thing is, only 1 race passed, and we don’t quite know yet how good is every car. So, this rule change actually might affect mostly some other team(s), and not McLaren… since it’s not just something specific to McLaren (like with the mini-DRS or DAS for Mercedes).
MacLeod (@macleod)
18th March 2025, 8:18
@mrcento That was the tyres which were gone and Max couldn’t keep up with McLaren.
But his tyres stabilize and the distance didn’t became bigger and he was making his gap with George larger.
We will never know what could happen if the rain didn’t came.
MazdaChris (@mazdachris)
18th March 2025, 12:36
These sorts of issues have come up before, and there are always the same mix of comments. Including, quite often, a sentiment that a team is operating outside of the ‘spirit’ of the regulations.
Let’s get one thing clear – the regulations don’t have spirits. They’re a set of technical requirements which a car must meet in order to be deemed legal for running in F1. By definition, such criteria must be SMART. In other words:
Specific – the regulations must define clear criteria with a binary outcome of pass or fail
Measurable – it must be possible for scrutineers to accurately check compliance
Achievable – the criteria must not set a standard which is impossible to achieve
Relevant – the requirements must have some clear purpose
Timely – the criteria must be measurable within an appropriate timeframe
If you want to talk in terms of spirits, then you’re talking about a set of ill-defined criteria which are not SMART. So if you believe that the spirit of the rules is that there should be no flexible aero elements on the car, this can’t be considered SMART.
It is not specific – you don’t have a clear definition of what constitutes a flexible aero element or a rigid one
It is not measurable – there are no defined criteria which could be used to determine compliance
It is not achievable – no matter how rigid a part is made, there will always be some flex
It is not relevant – chasing an impossible standard serves no clear purpose as it does not improve either the safety or the equitability of the cars
It is not timely – testing flex across the entirety of the aero elements in a simulated race condition, at racing speeds could only really be achieved using a wind tunnel. Clearly, wind tunnel testing every single car before (and possibly after) every single race could simply not be practically achieved.
You have to see the load test as a compromise. But it’s important to understand that the load test is the objective differentiator between compliance and noncompliance. If you pass the load test, the car is legal, because it is the load test itself that is the requirement under the rules, not any notion of intent or spirit. Those things are entirely subjective and, as such, cannot be measured or clearly defined.
In other words, if a car passes scrutineering and meets all of the objective requirements defined in the technical regulations, that car is entirely legal. No ifs, buts, maybes, and definitely no spirits.
Bob2 (@bob2)
19th March 2025, 0:50
Agree.
The point is, the FIA are changing the rules by changing the test. Doesn’t matter one bit what happens on the track, the rules state the test criteria, the cars are presented to scrutineering and pass the prescribed test. Nothing to see….
Then however, you get a clause like 3.15.1 which is basically a massive loophole the FIA can trigger to do whatever they want, whenever they want, to whoever they want. The fact that the FIA is allowed to, seemingly, influence the sporting outcome by triggering such clauses is questionable from a sporting and regulatory perspective.
3.15.1 Introduction of load/deflection tests
In order to ensure that the requirements of Article 3.2.2 are respected, the FIA reserves the
right to introduce further load/deflection tests on any part of the bodywork which appears to
be (or is suspected of), moving whilst the car is in motion.
At a minimum, the teams should claim any costs (and they would be significant..) associated with meeting in-season adjustments to the technical regulations (i.e. the testing criteria) to be exempt from the cost cap.