2015 Formula 1 Shell Belgian Grand Prix

[prisonermonkeys]

Therefore Pirelli, as the manufacturer, needs to ensure that tyre usage can exceed those parameters as the users of the product have explicitly indicated they want the option to exceed them.

Except that there will always be a limit to what the tyres can tolerate before failing outright. Pirelli parametres represent a buffer - conditions which, when observed, will ensure that the tyres continue to perform as expected. It doesn't matter that the teams want to operate outside the parametres; if you do that in real life, it's your fault. If the manufacturer of your dryer instructs you to clean out the lint filter before use or else risk a fire, then you can't accuse the manufacturer of providing a faulty product when you decide that you don't want to clean out the lint filter and subsequently cause a fire.

 

[TenEightyOne]

This site has a nice graphic. Doesn't seem like a noticeable drop off (lap 39 is slower, however lap 40 improves)
http://www.f1fanatic.co.uk/2015/08/23/no-drop-off-in-vettels-times-before-tyre-blow-out/

I'm not sure why there would be, Vettel was trying to drive a 1-stop and was presumably hitting target times to maximise the tyre life. We already know that if he'd spanked the car at max-speed on every lap the tyre would not have even got that far.

 

[niky]

I'm not sure why there would be, Vettel was trying to drive a 1-stop and was presumably hitting target times to maximise the tyre life. We already know that if he'd spanked the car at max-speed on every lap the tyre would not have even got that far.

If we're looking for an indication of where the tires might have started to go off, I do believe Vettel managed to stabilize the gap to Grosjean until about Lap 35 or 36... after which Grosjean reeled him in pretty quickly.

 

[Diabolik_za]

I addressed it exactly.

Pirelli were asked to make short life tyres and they asked that the max life be regulated. That regulation was refused.

Your argument is that they should then have made long-life tyres again despite having been asked to make short-life ones. If Ferrari want to risk a $100million sportscar by guessing against Pirelli on the tyre life then that's their fault, not Pirelli's.

Except that there will always be a limit to what the tyres can tolerate before failing outright. Pirelli parametres represent a buffer - conditions which, when observed, will ensure that the tyres continue to perform as expected. It doesn't matter that the teams want to operate outside the parametres; if you do that in real life, it's your fault. If the manufacturer of your dryer instructs you to clean out the lint filter before use or else risk a fire, then you can't accuse the manufacturer of providing a faulty product when you decide that you don't want to clean out the lint filter and subsequently cause a fire.

I think my response would cover both quotes above:

Pirelli is a manufacturer paid to design tyres that fulfill a specified role. They essentially requested a specification change to their product and was refused. If the manufacturer is providing a product and knows what they currently developed is unsafe given the expected usage, then they need to change the product to make it safe. You don't blame the user if they made it clear they want to use the product in that way. Its a bespoke product, not off the shelf (like your dryer example)

Again, my interpretation of tyre life relates to the tyre wear. Useful up to a point and then performance goes away. No need for it to explode.

I'm not sure why there would be, Vettel was trying to drive a 1-stop and was presumably hitting target times to maximise the tyre life. We already know that if he'd spanked the car at max-speed on every lap the tyre would not have even got that far.

Comes to down to how you view the tyre life. Stable decay with performance dropoff or stable decay with explosive performance dropoff.

 

[Barra333]

They essentially requested a specification change to their product and was refused

No, they asked for a recommendation to become a regulation because teams were using the tires outside of the role that they had been paid to design them for.
They were making the tires with a short lifespan (as FIA had asked), but teams were using them for longer than they were designed for.

Analogy time: You buy a carton of milk. It has a use by (or best before) date on the side. That is the date at which the manufacturer says "Yep, all good until now". After that date, the milk might be OK, but there is also a chance that it is off. If it goes off after the best before date, are you going to blame the manufacturer?

 

[prisonermonkeys]

If the manufacturer is providing a product and knows what they currently developed is unsafe given the expected usage, then they need to change the product to make it safe.

Except that Ferrari's usage of the tyre was not expected. Pirelli gave them the tyres and the parameters that would see the tyre maintain its integrity. Ferrari chose to disregard that, and the tyre failed as anticipated. How is it Pirelli's fault when Ferrari knowingly and willingly went against their advice and got the result Pirelli told them they would?

 

[Pezzarinho17]

I mentioned before that I think Ferrari have got an incorrect understanding of what is happening, the same incorect understanding simplified above. The performance decay followed by the performance "cliff" exist only for the tyre tread area alone. That is to say that if the meat of the tyre was worn down towards the canvas linearly, then at the point you start to get to the bonding layer between structure and rubber, performance would just fall away.

But the tyres suffer a lot more punishment than simply having their grip removed from the contact patch area. The tyres are the cars first piece of suspension connecting the car to the road. They flex as load is applied front to rear and left to right. They are driven over kerbs, bumps, and debris. Don't just think of the tyre as a strip of rubber, as the sidewall and internal structure receive just as much abuse over the course of the race.

The reason Pirelli put the issue down to wear though, is that they have an affect on each other. When the contact rubber wears down, you get closer and closer to exposing the inner structure of the tyre. This will in turn remove strength from the tyre as a whole. And finally, it also increases the speed at which the outside of the tyre is rotating. That's the reason circular blades and cutting wheels have a minimum radius imposed, because once you go below that, the outer circumference is spinning faster than the strength of the material will allow and the wheel may shatter...

 

[Diabolik_za]

No, they asked for a recommendation to become a regulation because teams were using the tires outside of the role that they had been paid to design them for.
They were making the tires with a short lifespan (as FIA had asked), but teams were using them for longer than they were designed for.

Analogy time: You buy a carton of milk. It has a use by (or best before) date on the side. That is the date at which the manufacturer says "Yep, all good until now". After that date, the milk might be OK, but there is also a chance that it is off. If it goes off after the best before date, are you going to blame the manufacturer?

Except that Ferrari's usage of the tyre was not expected. Pirelli gave them the tyres and the parameters that would see the tyre maintain its integrity. Ferrari chose to disregard that, and the tyre failed as anticipated. How is it Pirelli's fault when Ferrari knowingly and willingly went against their advice and got the result Pirelli told them they would?

So our point of departure is the initial specification from FIA (short-life span) and operating parameters as defined by Pirelli. I haven't seen the official specification or operating parameters so I can't respond. If the FIA defined short-life span as period until structural failure and Pirelli's operating parameters specifically states the 50% Prime and 30% Option usage then it would be difficult to argue against. I don't accept the 2013 proposal as proof though.

 

[Famine]

They essentially requested a specification change to their product and was refused.

No, it recommended that legislation was passed to account for the specification of the tyres it had been asked to make, and that was refused.


To reiterate, Vettel was attempting to get 70km more use out of the Medium tyre than any driver but a Manor/Marussia driver had ever managed. At Spa - Spa! While cutting corners, onto less clean parts of the track and across kerbing.

When the strategy failed with 1 lap to go, he, after a debrief from the team, went in front of the cameras to claim he's never gone off track and the tyre situation is bull:censored:, while the team itself is claiming that Pirelli said nothing (something we cannot verify, unlike Vettel's claims) and it's all Pirelli's fault.

 

[Barra333]

So our point of departure is the initial specification from FIA (short-life span) and operating parameters as defined by Pirelli. I haven't seen the official specification or operating parameters so I can't respond. If the FIA defined short-life span as period until structural failure and Pirelli's operating parameters specifically states the 50% Prime and 30% Option usage then it would be difficult to argue against. I don't accept the 2013 proposal as proof though.

The FIA wanted teams to have to make at least 2 stops to complete a race. So unless one of the compounds is made of cheese, trying to do 60% of a race on the other was never really going to end well, especially, as @Famine keeps repeating, at Spa while they are running on the wrong side of the the kerbs.

 

[Munsoor]

Unless Rosberg sees some very sudden upturn in form Hamilton is going to run away with it.

The story of the season for me has to be Mclaren Honda and Alonso. The talents of the best driver on the grid are being wasted, a real shame in my view. I suspect that Alonso's patience will run out sooner than Honda getting their act together.

 

[Pupik]

Twenty-seven years ago, Gerhard Berger drops out of the Detroit Grand Prix with a tire failure. He kicked the tire symbolically after getting out of the car, and that was it. No media fuss at Goodyear, the lone supplier of tires to Formula One at the time.

I think the biggest desired changes to the sport have nothing to do with vehicle performance, rules, and sporting regulations. It's the whining, finger-pointing, and skullduggery which needs to find a long walk off a not-so-distant cliff.

 

[prisonermonkeys]

It's the whining, finger-pointing, and skullduggery which needs to find a long walk off a not-so-distant cliff.

I think that's because we're constantly looking for a scapegoat, someone to blame for the current state of affairs as it will mean that there is an easy fix. The reality is that the teams have far too much influence in the sport and pursue their own agenda while pretending that it's in the interests of the sport. Fixing it would mean handing the reins over to an unpopular entity on the FIA, but they're only unpopular because the teams waged a public relations campaign against them to get that power in the first place. It's like the EPL if the players had input on every single refereeing decision.

 

[Diabolik_za]

No, it recommended that legislation was passed to account for the specification of the tyres it had been asked to make, and that was refused.

As I said above, it depends on the original specification and operating parameters defined. I can't find it online so I can't respond.

The FIA wanted teams to have to make at least 2 stops to complete a race. So unless one of the compounds is made of cheese, trying to do 60% of a race on the other was never really going to end well, especially, as @Famine keeps repeating, at Spa while they are running on the wrong side of the the kerbs.

The FIA only requires one stop per race with a compound change. So at the very least, one compound has to be able to complete 50% of the race distance. It would be have to be higher than 50% otherwise both compounds are equal in terms of durability with one having a significant pace advantage. 60% is viable.

Can someone provide a link to the official specifications/parameters? There's a lot of wants and recommendations but no official basis provided.

 

[Barra333]

The FIA only requires one stop per race with a compound change. So at the very least, one compound has to be able to complete 50% of the race distance. It would be have to be higher than 50% otherwise both compounds are equal in terms of durability with one having a significant pace advantage. 60% is viable.

It requires at least one stop, but the desire was for teams to make 2+, hence the soft compound being good for one third race distance (at best).

I don't expect anyone to have access to the agreement made between FIA and Pirelli about the tires, since it is probably commercial in confidence.

 

[Famine]

As I said above, it depends on the original specification and operating parameters defined. I can't find it online so I can't respond.

I'd be reasonably sure that this is kept between the manufacturer and the FIA or FOM. It doesn't appear in the technical regulations because it's not something over which the teams have control.

The FIA only requires one stop per race with a compound change. So at the very least, one compound has to be able to complete 50% of the race distance. It would be have to be higher than 50% otherwise both compounds are equal in terms of durability with one having a significant pace advantage. 60% is viable.

Based on what?

 

[jimipitbull]

Except that there will always be a limit to what the tyres can tolerate before failing outright. Pirelli parametres represent a buffer - conditions which, when observed, will ensure that the tyres continue to perform as expected. It doesn't matter that the teams want to operate outside the parametres; if you do that in real life, it's your fault. If the manufacturer of your dryer instructs you to clean out the lint filter before use or else risk a fire, then you can't accuse the manufacturer of providing a faulty product when you decide that you don't want to clean out the lint filter and subsequently cause a fire.

You probably would have received more likes using a vacuum cleaner analogy.

 

[HKS racer]

No, it has absolutely nothing to do with it. How does an in-season test with a 2013 Mercedes (and the second one in 2015 with the same 2013 Mercedes) relate to the consistency of Pirell's position that it recommends against running a 2014-2015 tyre to 65% race distance?

It doesn't.
Not Vettel - he told us he didn't.

Incidentally, was everyone also trying to get 70km more out of a set of tyres than had ever been achieved before?

I already told you Pirelli was perfectly aware of Ferrari 1 stop strategy at 11.00 am. They were also aware of track cutting at Eau Rouge Radillion and Stavelot since Friday, because even in practice everyone was cutting the track.

This is my last post on the matter.

 

[Diabolik_za]

I'd be reasonably sure that this is kept between the manufacturer and the FIA or FOM. It doesn't appear in the technical regulations because it's not something over which the teams have control.

So there is no basis to say that 50% Prime and 30% Option is an official operating parameter. The 2013 document can be interpreted as a spec change just as much as the request to enforce of an official operating parameter.

Based on what?

On the reasoning before that. Barra333 used the rationale that FIA wants at least 2 stops to say 60% isn't viable. I used the fact that the FIA only requires 1 stop to say it is.

 

[prisonermonkeys]

And what were they supposed to do? Change the build of their tyres on the spot?

 

[Pezzarinho17]

I already told you Pirelli was perfectly aware of Ferrari 1 stop strategy at 11.00 am. They were also aware of track cutting at Eau Rouge Radillion and Stavelot since Friday, because even in practice everyone was cutting the track.

... And if Vettel had pitted on lap 15 and not on lap 13 then that 1 stop would have been ok...

 

[Nessy]

... And if Vettel had pitted on lap 15 and not on lap 13 then that 1 stop would have been ok...

Indeed. It's a very thin line between getting it right and getting it wrong. On this occasion Vettel and Ferrari failed with their strategy. I think they should just see it as a valuable lesson learnt.

 

[LMSCorvetteGT2]

If we're looking for an indication of where the tires might have started to go off, I do believe Vettel managed to stabilize the gap to Grosjean until about Lap 35 or 36... after which Grosjean reeled him in pretty quickly.

Ah but that reasoning as Lotus suggest is due to the fact that they claim Mercedes let them perform at the peak map setting from about that point onward to the end, to ensure they had enough to catch and pass Vettel. Thus this can't fully or safely be put down to fall off of the tires.

Twenty-seven years ago, Gerhard Berger drops out of the Detroit Grand Prix with a tire failure. He kicked the tire symbolically after getting out of the car, and that was it. No media fuss at Goodyear, the lone supplier of tires to Formula One at the time.

I think the biggest desired changes to the sport have nothing to do with vehicle performance, rules, and sporting regulations. It's the whining, finger-pointing, and skullduggery which needs to find a long walk off a not-so-distant cliff.

Good luck finding tons of others who agree, especially in Seasons like this where you can predict the winner of these last 8 races. I agree, the crying over who is exploiting a loop hole to "no the engine manufacture sucks not our chassis" to the yearly Pirelli hate, it all gets old when there are far more interesting news bits. Driver switches, rule updates, new venues and so on are far more interesting than these more squabble like bits. But every one likes a fight, which is why this thread is still much alive after the the GP, even more so than post race talk after the very interesting Hungarian GP.

 

[Famine]

I already told you Pirelli was perfectly aware of Ferrari 1 stop strategy at 11.00 am.

According to Ferrari - a piece of information that cannot be corroborated from the team that sent its driver out to lie to the cameras...

They were also aware of track cutting at Eau Rouge Radillion and Stavelot since Friday, because even in practice everyone was cutting the track.

Except Vettel. He didn't go off the track at all because he said he didn't.

You have to believe that, or you can't take Ferrari's comments about the strategy at face value as you're doing.

Taking Ferrari's comments about the strategy at face value requires you to believe that:
* Vettel didn't go off track.
* Ferrari told someone other than Vettel's engineers their pit strategy.
* Pirelli, despite calling for a legislated 50% race distance cap on any set of the prime tyre, didn't warn Ferrari about trying to do 65% race distance on one set of the prime tyre.
* Pirelli, despite knowing that no-one had ever done more than 150km on a front-running car on one set of Medium compound tyres, didn't warn Ferrari about trying to do 210km on a set.

One of these things is demonstrably false. Three of these things cannot be verified, because they are Ferrari's claims only and, of those, one flies in the face of known data and one flies in the face of known actions.

So there is no basis to say that 50% Prime and 30% Option is an official operating parameter.

That "so" there is misplaced. Nothing you said leads on from the part of the post you quoted.

There is a basis to say that the people who make the tyre to the specification they've been asked think that it is safe for a single set of tyres to go 50%/30% race distance, but not be able to guarantee safety beyond that point.

In which case it becomes a question of why Ferrari thought it was fine to push the tyres so far beyond what was known to be safe into a territory where the tyre may no longer be safe. For 70km. At Spa. On a kerb-hopping car.

The 2013 document can be interpreted as a spec change just as much as the request to enforce of an official operating parameter.

It's not a spec change if the spec doesn't change, so no you can't interpret it as that. It's a request for a change of rules to reflect the specification - to give safety margins.

On the reasoning before that. Barra333 used the rationale that FIA wants at least 2 stops to say 60% isn't viable. I used the fact that the FIA only requires 1 stop to say it is.

The FIA requires 1 stop because they require drivers to use both sets of compounds. That has nothing to do with tyre life, so to draw the conclusion that a tyre must be able to do 60% of a race because the FIA only requires drivers to use both sets of compounds is a colossal and irrational leap.


This week we're all talking about closed cockpits because a driver has been killed by debris in a fluke and roughly calculated at in excess of millions to one incident, because driver safety must be paramount. So why are we so ready to dismiss what tyre manufacturers say when they say what the safe margins of the tyres built to the specifications they've been asked to build are?

 

[Diabolik_za]

That "so" there is misplaced. Nothing you said leads on from the part of the post you quoted.

Let me rephrase it then, unless someone can reference official documentation that the operating parameters are 50% Prime and 30% option, its just hearsay.

There is a basis to say that the people who make the tyre to the specification they've been asked think that it is safe for a single set of tyres to go 50%/30% race distance, but not be able to guarantee safety beyond that point.

Hearsay. Pirelli's response was to refer to a 2013 proposal that was rejected. Had they said that Ferrari exceeded the operating parameters of the tyre, then we wouldn't be having this discussion. Its a very simple statement to make.

The relevance of the 2013 proposal on 2015 tyres is also debatable. Pirelli's website talks to the evolution of the tyre from 2014 and numerous improvements and changes made.

It's not a spec change if the spec doesn't change, so no you can't interpret it as that. It's a request for a change of rules to reflect the specification - to give safety margins.

Again, hearsay. Pirelli may not have built a tyre to match specification and this rule would have allowed them to continue building an inadequate spec tyre. Its a specification change in that they would not need to produce the original specification.

The FIA requires 1 stop because they require drivers to use both sets of compounds. That has nothing to do with tyre life, so to draw the conclusion that a tyre must be able to do 60% of a race because the FIA only requires drivers to use both sets of compounds is a colossal and irrational leap.

Based on what? I didn't say "must do 60%". I said "60% is viable".

 

[Famine]

Let me rephrase it then, unless someone can reference official documentation that the operating parameters are 50% Prime and 30% option, its just hearsay.

It would be if that's what anyone was saying. Which they aren't.

What Pirelli said was that it wanted, for the start of the 2014 season with the V6 Hybrid cars, a hard, legislated limitation on the distance the tyres could be used.

Hearsay.

Not even slightly. Pirelli makes the tyres that it was asked to make. I seem to recall it saying exactly that after the Silverstone debacle - caused, incidentally, by teams completely ignoring Pirelli's fitment, camber and pressure recommendations and then letting the drivers cut corners (particularly turn 4).

Pirelli's response was to refer to a 2013 proposal that was rejected. Had they said that Ferrari exceeded the operating parameters of the tyre, then we wouldn't be having this discussion. Its a very simple statement to make.

Except it wouldn't be true.

What Pirelli has said - that it wanted legislation to limit tyre distance for the 2014 season - is at least verifiable.

The relevance of the 2013 proposal on 2015 tyres is also debatable.

Of course it is - though bear in mind that the proposal in November 2013 was for the 2014 season, with the new V6 Hybrid cars. The technical specification for the cars hasn't changed notably from 2014 for 2015.

Again, hearsay.

Sure, except that the request was literally to introduce legislation for the 2014 tyres.

Pirelli may not have built a tyre to match specification and this rule would have allowed them to continue building an inadequate spec tyre. Its a specification change in that they would not need to produce the original specification.

That's just wild speculation.

Based on what?

The Technical and Sporting Regulations for F1.

I didn't say "must do 60%". I said "60% is viable".

But you didn't explain why it is. The fact that the cars must use both sets of compounds in a race (unless the race is called as wet), thus most stop at least once (again, unless the race is called as wet), is a regulation not connected to the life of the tyres. The rule was, in fact, introduced in 2007 (when Bridgestone was the only tyre supplier) to promote on-track racing to counteract F1's processional image, so to draw the conclusion that you have to be able to do any race on two sets of tyres is not sound.


To reiterate:

This week we're all talking about closed cockpits because a driver has been killed by debris in a fluke and roughly calculated at in excess of millions to one incident, because driver safety must be paramount. So why are we so ready to dismiss what tyre manufacturers say when they say what the safe margins of the tyres built to the specifications they've been asked to build are?

 

[daan]

Twenty-seven years ago, Gerhard Berger drops out of the Detroit Grand Prix with a tire failure. He kicked the tire symbolically after getting out of the car, and that was it. No media fuss at Goodyear, the lone supplier of tires to Formula One at the time.

Not to mention Adelaide '86 where Keke Rosberg lost a (possible) win and Mansell lost a championship. I don't recall a witch hunt against Goodyear at the time. How could a tyre explode with no warning? Apart from Mansell, who cared?

 

[IforceV8]

Here are the lying track cutting finger wagging drivers lap times.

29 1:55.316 Fastest lap
30 1:55.523
31 1:55.432
32 1:55.443
33 1:55.497
34 1:55.761
35 1:55.884
36 1:55.711
37 1:55.520
38 1:55.696
39 1:56.407
40 1:55.949
41 1:56.116
42 P 3:03.554

Used option times
1 14:09:00
2 1:57.106
3 1:56.388
4 1:56.867
5 1:56.676
6 1:56.737
7 1:56.652
8 1:57.346
9 1:57.179
10 1:57.459
11 1:57.478
12 1:58.217
13 1:57.926
14 P 2:02.971

Grosjean

29 1:55.617
30 1:56.019
31 1:55.194
32 1:55.043
33 1:55.299
34 1:55.004
35 1:55.333
36 1:55.311
37 1:54.779
38 1:55.397
39 1:56.189
40 1:55.915
41 1:56.311
42 1:56.254
43 1:56.341


This was 2 days ago. http://www.bbc.com/sport/0/formula1/34063824 Still waiting to hear what Pirelli has to say after checking the other 3 tires.

 

[ukfan758]

Will someone please explain to me why the tyres have become a flame war debate like Silverstone 2013? I did not watch the race so I have no idea what happened.

 

[Dennisch]

Will someone please explain to me why the tyres have become a flame war debate like Silverstone 2013? I did not watch the race so I have no idea what happened.

Vettel's almost fresh, totally not abused, never went off track tyre blew to pieces 250 meter after going through Eau Rouge.