The Condition of the track at Indianapolis

[JeremySmith]

With all the talk about tyres over the last few days it struck me that no one has talked about the current condition of the track at Indie..We know that it has been resurfaced and that they had to "diamond grind" the entire track in the end to remove bumps. I have also heard it mentioned that several test sessions have been cancelled at the facility. The track looked rather strange to me when I was watching the Indie 500.. Does anyone think that this might have contributed to the problem at the USGP .. One last thought, does F1 not have some kind of advance party that arrives at the track to check that everything is okay?

[blueflagger]

The oval was diamond-ground but not the interior part of the road course.

The grinding created a more level but rough surface that is particularly hard on soft tires. Coming off the smooth surface of the road course onto the rough oval at high speeds and the lateral stress on the tires caused a lot of distress to the rear tires.

[eatapc]

The track was in great condition. The grinding was a careful attempt at aging the new surface to make it more like an ideally worn-in track.

From SpeedTV last month: "A new asphalt surface that gave fits to the first drivers who tested it but was given a nod of approval after a diamond grinding procedure smoothed out the inconsistencies. Before the grinding, drivers reported that their ability to control the cars went on and off like a switch, that the surface went from extremely adhesive to ice-like without warning. After the grinding, though, drivers who tested last week for the Menards Infiniti Pro Series and those who went through rookie orientation Sunday and Monday deemed the surface more consistent. Some engineers are speculating that the color of the surface after the grinding – a chalky gray shade – might make the track less sensitive to sunlight and changes in temperature. However, drivers who have reached top speed at the track say the surface is smooth and stable. 'If the track is as smooth as we think it will be, we’ll be able to run the cars lower,' Rice said. 'It will allow us to trim out that much more because it will make the underwing that much more effective.'"

Interestingly, Al Speyer, Director of Firestone Racing, said that in spite of the new surface, the tires chosen for this year's Indy 500 ended up being, after extensive testing, the same spec as last year. Michelin cannot claim that the new surface presented unexpected problems. Said Speyer: “The test confirmed Firestone’s Race Tire Development group made the right call in its tire selection for this May. Not surprisingly, the tire specification chosen is identical to the 2004 tire spec that performed so flawlessly here a year ago. Tire wear was even better than we had anticipated at that test, and we expect it to continue improving as the surface gets ‘rubbered in’ over the next few weeks with thousands of laps run on it. Of course, tire management is always an issue at Indianapolis...."

The oval was in perfect condition. The infield part of the track, however, was slippery in comparison, thus posing an interesting setup dilemma for the teams.

[JeremySmith]

That is an excellent responce eatapc! Thank you I have just be reading an article about the Firestone 2004 spec tyre used by the IRL. BTW I meant to say that the OVAL portion of the track had been resurfaced, I did not mean the infield portion sorry about that.

blueflagger are you saying then that the new surface puts a greater strain on tyres? I have not seen the track close up but it does look quite abrasive, it might well be smooth from a bump point of view of course..

[blueflagger]

It was pretty abrasive on my shoes. I worked the event and was out on the oval in a couple of places. The racing line of the 500 was smoother due to wear of course, but out of necessity F1 has a different line.

[rustyfan]

There is nothing wrong with the track. Michelin as a whole, on the other hand...

And while the resurfacing probably did contribute to the problems, it was up to Michelin to come prepared. It's not like it's a secret the work was made, and they should have taken that into consideration.

Hm, I just realized what this whole farce reminds me of - the CART fiasco at Texas in 2001.

Not sure which one ****es me off the most though.

[BootsOntheSide]

Even if the track surface was worse trhan last year's, or was compromised for the F1 cars for the benefit of the 500, it doesn't really deflect any blame form Michelin for their failure to do all their research and plan ahead.

[blueflagger]

It was up to Michelin and Bridgestone to come prepared but Bridgestone definitely had an advantage. Remember they are a daughter company to Firestone, who supplies tires for the 500 and therefore would have a heckuva lot of testing data to rely on. That's an advantage that Michelin would have a hard time overcoming.

[Dani Filth]

http://www.pitpass.com/fes_php/pitpa...s_art_id=24932

it says here that Firestone used same the same spec tyres both in 2004 and 2005

[blueflagger]

What Firestone used doesn't show what data they may have passed on to Bridgestone though.

All in all, it doesn't matter now, the damage is done. I'm glad the teams didn't race on unsafe tires but it sure was disappointing for us marshals as well as for the fans.

[avsfan733]

it wasn't lateral load that killed michelins tyres it was vertical load

[eatapc]

Avsfan, I was under the impression that both vertical and side loads were, in combination, producing the failures. Probably. Michelin hasn't released a full report. Certainly turn 13 at Indy produces uniquely high side loads, so it strikes me as odd that you would conclude that the side loads were not part of the equation.

Craig Scarborough's technical analysis makes it clear: "the side loading on the tyres was making the sidewall detach from the tread, leading to total tyre failure. Other teams checked their tyres and all bar two teams (Renault and McLaren) were found to be in the early stages of a similar failure."

[eatapc]

Originally Posted by blueflagger

What Firestone used doesn't show what data they may have passed on to Bridgestone though.

In all likelihood, Firestone told Bridgestone, "Don't do anything drastic to your tires." From everything I've read, the construction of the Bridgestones is inherently more suited to the severe strains of the Indy track, so the Bridgestone engineers didn't have to solve a problem that didn't exist.

P.S. Thanks for that firsthand report on the track surface.

[knock-on]

Originally Posted by eatapc

In all likelihood, Firestone told Bridgestone, "Don't do anything drastic to your tires." From everything I've read, the construction of the Bridgestones is inherently more suited to the severe strains of the Indy track, so the Bridgestone engineers didn't have to solve a problem that didn't exist.

P.S. Thanks for that firsthand report on the track surface.

I heard that BS still used the "conservative" tyre though even with the Firestone feedback.

[paul-collins]

Originally Posted by eatapc

From SpeedTV last month:
...
Interestingly, Al Speyer, Director of Firestone Racing, said that in spite of the new surface, the tires chosen for this year's Indy 500 ended up being, after extensive testing, the same spec as last year. Michelin cannot claim that the new surface presented unexpected problems. Said Speyer: “The test confirmed Firestone’s Race Tire Development group made the right call in its tire selection for this May. Not surprisingly, the tire specification chosen is identical to the 2004 tire spec that performed so flawlessly here a year ago. Tire wear was even better than we had anticipated at that test, and we expect it to continue improving as the surface gets ‘rubbered in’ over the next few weeks with thousands of laps run on it. Of course, tire management is always an issue at Indianapolis...."

eatapc, did you insert that line? It seems odd that it would be there in a piece that was written last month.

[eatapc]

Paul: Re-read my post. I quoted two separate sources, one was Speed TV, one was Firestone. There were closed quotes on the paragraph from Speed. The next paragraph was my way of commenting and segueing into a quote from a Firestone statement. My comment about Michelin was not meant to be connected directly to the story last month on Speed. I probably could have made that less ambiguous. Sorry -- sometimes it's hard to edit your own stuff; I didn't realize it was unclear.

[Baritone2400]

its simple they should have adapted tyres to a track they've been to 4 times in the past!!

[Don K]

Originally Posted by knock-on

I heard that BS still used the "conservative" tyre though even with the Firestone feedback.

Yep.

Kees van de Grinten (the Bridgestone guy for Ferrari) said on thursday for the race, that Bridgestone had kept quite some error of margin for their "safer" spec tyre, and that he expected Michelin to have a much small error of margin.

[Valve Bounce]

Originally Posted by Baritone2400

its simple they should have adapted tyres to a track they've been to 4 times in the past!!

This is about as silly a post as anyone could come up with in the middle of a thread stating not only that the track was resurfaced but that the oval section was diamond ground to produce a very abrasive surface (see blueflaggers post).

Diamond grinding does several things, inter alia
1) Remove small bumps
2) Remove any asphalt coating the surface of the aggregates at the contact surface
3) Grinds the aggregates at the contact surface, producing much sharper aggregate surfaces at the contact surface.

The result, as blueflagger pointed out with first hand experience, is a much more abrasive surface, and for anyone with even high school physics knowledge, a very significant increase in friction angle which permits an increase in sideways grip.

That Firestone may have passed on this knowledge to Bridgestone is significant, because Michelin did not have the opportunity to test their tyres on this surface.

Lets stop ranting anymore and discuss the technical details like adults in a sensible manner.

And NO!! I did not OD on drugs nor medication before writing this post.

[eatapc]

Originally Posted by Valve Bounce

That Firestone may have passed on this knowledge to Bridgestone is significant, because Michelin did not have the opportunity to test their tyres on this surface.

From Peter Windsor: "Do you know how many teams from Michelin actually did the pre-USA tire test to select the correct tire for Indianapolis? Two — Felipe Massa and Anthony Davidson — everyone else was at Silverstone."

What irritates me is that Michelin released a statement claiming that they were surprised at the condition of the Indy track. Nonsense. They had problems last year, they were warned by the FIA several weeks ago, and they knew the oval had been ground for smoothness and grip prior to the Indy 500. The Michelin program was derelict in its preparations.

[N I Tram]

First and foremost Michelin were responsible, if they really were so negligent regarding testing. However, how come Massa and Davidson didn't notice this issue - surely they did a 10-lap run at some point?

[eatapc]

I'm assuming that Massa and Davidson tested the tires at a track other than Indy, since Michelin's press release says that testing at Indy was not possible. I think Windsor's point point was that Michelin and their teams were unconcerned about tire selection at Indy; they only bothered to gather data from two cars. They didn't take seriously the tire questions from last year or the warnings from the FIA a few weeks ago. It's strange to me that Renault and McLaren didn't want to have more input.

As to the track surface itself (at Turn 13), I'd say it was near perfect for racing. Smooth and grippy without being too abrasive -- an ideal compromise. No one at Indy was complaining about excessive wear; Firestone remarked that their tires were, if anything, holding up better this year. What more can you ask of a track surface?

One thing I'm not clear about: The online articles I read about diamond grinding mentioned cutting grooves in the track for better drainage -- more grip when wet. But grooves would create less grip when dry, just like on a tire. Was the surface of the Indy oval grooved? Blueflagger, any comments?

[JeremySmith]

Interesting eatapc..Also I wonder if the direction that the diamond grinding took place would have made any difference? another words they would have run the machine counter to the direction that F1 cars race that circuit.. BTW there are NO attempts on my behalf to lay any blame with IMS..This is purley for discussion purposes. One point that seem's odd to me is that tyre companies can produce a tyre that will take severe punishment over curbs but had a problem in this situation with a six degree banking?

[Tone]

The diamond cut grooves run parralel to the track so wouldnt be directional , I doubt that any consideration was given to wet races as the grooves were added for IRL.

Also firestone used the same tyres for the 2004 and 2005 race and said that the grooves gave the tyres a slightly better wear rate..

So it would appear that Michelin's 2004 data should have been good enough to make a suitable tyre.

[paul-collins]

Well, they would be directional if you consider transverse loading of tires. But I think you're right that the difference between clockwise and anticlockwise would be minimal.

Does anyone know when the F1 test occurred? I've just about had it with google, and pitpass and a bunch of other sites. No one seems to have any news about it.

The grinding took place mid-April; IMS doesn't have any news pieces on any test, and of course all of May was taken up with the 500. Was the F1 "test" at Indy supposed to be at the start of June?