Close look at Vettel's Tire before the moment...

[wuzak]

To give you an idea of what the tyre goes through in racing, here is a clip from V8Supercars.

https://www.youtube.com/watch?v=ZGgWg9Q2TW8

V8s are heavier, but don't have teh downforce or performance of an F1 car.

You can see how much the tyre deforms under load - and that is on a 17" rim.

[djos]

Now on the top of Eau Rouge, just at thy get on the Kemmel straight.

http://s1193.photobucket.com/user/johnc ... 6.jpg.html

The bulge in the sidewall shows clearly the sidewall has a flaw or has been damaged (the latter not very likely given it's location imo) and is about to fail which imo shows the Pirelli claim of a wear related failure to be total BS - imo this vindicates Ferrari.

[PlatinumZealot]

Now on the top of Eau Rouge, just at thy get on the Kemmel straight.

http://s1193.photobucket.com/user/johnc ... 6.jpg.html

The bulge in the sidewall shows clearly the sidewall has a flaw or has been damaged (the latter not very likely given it's location imo) and is about to fail which imo shows the Pirelli claim of a wear related failure to be total BS - imo this vindicates Ferrari.

Not reallly.. It can still be wear damage. Wear is gradual disintegration of material through use or other external factors. A "baby" head can definitely be caused through wear. Obviously The tyre is running at a low pressure and riding heavily on the sidewall through those right handers. I can bet if Vettel did drove the same way on another fresh set of tyres it would happen again.

[TAG]

But I would suggest that they are not exactly at the same place, and that Vettel appears to be turning left slightly, whereas Grosjean is not. To confirm, see where they are looking - Vettel is looking left, Grosjean is looking right.

Grosjean was following Vettel at about .6 second behind. It's H.A.M. to work a DVR to stop exactly when you want it. But exact, exact spot, no. Within 3 feet of the exact spot, yes.

The world feed was entirely more fascinated with what Kyviat was doing so a lot of the tail happiness Vettel was showing was due to wear, the tires had gone off. What I'm trying to show with the example is that obviously Vettel's tire was damaged before it blew. That the tire was under inflated before it blew and every video that I've reviewed of the final few laps shows Vettel consistently going further out over the curbs than Grosjean.

If a Pirelli engineer was driving the car, he'd agree that a tire shouldn't blow. No one is arguing that point, but it's clear that Rosberg's issue on Saturday and Vettel's on Sunday are markedly different at least in the way they manifested themselves.

[mertol]

If they are different then pirelli has 2 smaller? problems to fix instead of one. Doesn't make it any better IMO.

[TAG]

I love how we demand that bags of rubber spinning around at 300 kph never ever fail. There were over 1000 tires used over the Spa weekend. How many tires have been used without issue since Silverstone 2013? The FiA refuses testing, refuses suggestion from Pirelli to reduce the tire life rating and it's Pirelli's issue to fix?

It's dangerous, and I get it and I agree if something could be done to assure the safety of the drivers, it should be done. But it's absolute insanity to demand that something never fail.

We might as well demand from Boeing that their air planes never crash.

[dans79]

We might as well demand from Boeing that their air planes never crash.

Actually we do, at-least here in the US, we even have a government agency that investigates every crash to determine the cause. If the Airline is at fault they face fines and possible criminal charges. The same thing can happen to the manufacture if they are deemed to be at fault.

it happens with tires as well.
https://en.wikipedia.org/wiki/Firestone ... ontroversy

[Edax]

We might as well demand from Boeing that their air planes never crash.

Actually we do, at-least here in the US, we even have a government agency that investigates every crash to determine the cause. If the Airline is at fault they face fines and possible criminal charges. The same thing can happen to the manufacture if they are deemed to be at fault.

it happens with tires as well.
https://en.wikipedia.org/wiki/Firestone ... ontroversy

It is a bit more complex than that.

First of all, zero failures is easier to achieve in reality than in theory. Proving zero failures requires per definition an infinite amount of tests. Therefore manufacturers are asked to demonstrate a certain failure probability. For instance the upper failure requirement for airplane batteries is one failure per billion flight hours. But nothing is ever certified for zero failures.

Secondly like the FAA the FIA is a regulatory organisation. You can say that Pirelli has put a bad product on the track. However the FIA has allowed in on track and did so after reviewing the design, the design validation and the quality control. They are tasked with guarding safety and have a full mandate to enforce it.

If the Pirelli's are not safe then it is as much a failure of the FIA as Pirelli. So in these kind of cases they will likely not take harsh action, except in cases of real negligence, like Benetton removing a protection from a fuel rig to increase flow speed and lighting up the pitlane as a result.

[Just_a_fan]

S'funny, the whole "make tyres that don't last" thing came from FOM, not the FIA. FOM (a.k.a. Bernie) are laughing all the way with this latest controversy. They're getting lots of air time for F1 and the FIA and Pirelli are taking all of the flack. Clever old Bernie.

[l4mbch0ps]

It is a bit more complex than that.

First of all, zero failures is easier to achieve in reality than in theory. Proving zero failures requires per definition an infinite amount of tests. Therefore manufacturers are asked to demonstrate a certain failure probability. For instance the upper failure requirement for airplane batteries is one failure per billion flight hours. But nothing is ever certified for zero failures.

How can they ever certify something for that kind of lifetime? That's 114,000 years. There's no way they've demonstrated that kind of metric in any other way than theoretically.

[dans79]

If the Pirelli's are not safe then it is as much a failure of the FIA as Pirelli. So in these kind of cases they will likely not take harsh action, except in cases of real negligence, like Benetton removing a protection from a fuel rig to increase flow speed and lighting up the pitlane as a result.

just an fyi, I was referring to the NTSB, not the FAA.
https://en.wikipedia.org/wiki/National_ ... fety_Board

It is part of the issue though, other than the drivers and to the a lesser extent the teams no one cares about doing real investigative work. Bernie just wants an interesting show, Pirelli wants good press, and the FIA wants nothing but good press as well most of the time.

I can't be the only one that thinks it's a conflict of interest, that Pirelli is the one who investigates tire issues. Several drivers have said as much.

[Edax]

It is a bit more complex than that.

First of all, zero failures is easier to achieve in reality than in theory. Proving zero failures requires per definition an infinite amount of tests. Therefore manufacturers are asked to demonstrate a certain failure probability. For instance the upper failure requirement for airplane batteries is one failure per billion flight hours. But nothing is ever certified for zero failures.

How can they ever certify something for that kind of lifetime? That's 114,000 years. There's no way they've demonstrated that kind of metric in any other way than theoretically.

There is multiple ways to get that kind of low probabilities

Say you have a heater which is safeguarded by a thermocouple and a mechanical temperature switch. The probability of the heater failing or the thermocouple or the switch failing is .001 then the probably of the heater catching fire is 0.0000001 as it requires a combined failure of all three. So you combine measurable probabilities into an immeasurable one.

Another method is if you can accelerate. Say you have a switch and it switches on average 2 times a day. If you take 30 seconds for a switch it only takes you 6 hours to simulate one year of usage. Or you use an overstress, overtemperature etc.

And 114000 years sounds like a lot, but if you spread it out over a production series of thousands it is not that much.

I can't be the only one that thinks it's a conflict of interest, that Pirelli is the one who investigates tire issues. Several drivers have said as much.

It is not that uncommon. For an investigation you need the right equipment and the right knowledge. For highly specialized products that is sometimes only found at the manufacturer. Conflicts of interests are then disarmed by having representatives of the different parties (lawyers, (hired) specialists) on site involved in the investigation.

Also you have to consider that if this is a design problem, Pirelli would like to know and to solve it. Say they falsely conclude that it was not a tire problem, and the next race a serious accident happens. Better to come clean now.

[marcush.]

so at least F1t has something to chew properly on -that´s good News after all.

The whole issue proves what we all should be Aware of:You just cannot test for each and every failure case and derive a Zero failure possibility Statement from it .This is complete and utter bs.
sure you will get some result and maybe even some sort of Quality .But considering the sheer number of variables not in the Hands and under control of Pirelli it is near impossible to test the product to all These possible factors .
Considering the issue has occured only with one car and under a Special Set of circumstances very obviously Pirelli either has a Quality Problem - the tyre did not hold up against the loads it was designed for - or Pirelli did underestimate the loads the tyre might be subject to in the hands of Mr.Vettel. No other possibilty there.
If Pirelli had thought it would be unsafe to use the tyre for more than 22 laps they be idiots to let them run for anything more than 15.
but Pirelli said the tyre would survive 40laps and it didn´t .The tyre had at least acceptable Performance up to ist sudden failure .And it failed during ist intended use .
I don´t think you can design a tyre ignoring things like curbs ,debris etc -it´s your choice of what your tyre has to survive without compromising its life.

[strad]

bill shoe , Brings up an interesting point.
We have seen many times in their thermal imaging that the car leaves the pits with a tire that comes out hot and cools rather than a cool tire that warms.
SO if it comes out of the pits at a certain pressure under the blankets at a hotter temp when it cools the pressure drops?

[PlatinumZealot]

Lets us all be honest here Look how many times we see brakes fail. Brake failures are at least as serious. Granted, most of the brake faliures are not as sudden but there have been a few sponatanous ones... And did we see any ranting towards carbon industries or brembo or wheover they may be? Not even a peep. I don't know why.. But i am just saying...