IRL Car Problem

[Methanolandbrats]

OK, how f'n hard can it be to figure out the problem? First of all, what changed from last year? Just go from there. The level of retardation in the IRL is staggering. Geeezus, even Minardi engineers with a rented windtunnel could probably figure it out in a couple days. Ferrari, Williams and McLaren aero guys could figure it out in the pub, drunk, scribbling on the back of a napkin in 15 minutes.:mad:

[Turn7]

Well, first you have to find out if they want the cars "fixed".

The braintrust at the IRL may think that flying cars are a good way to get on the local news around the country. Playing off of the Nascar revolution and letting spectacular crashes and mangled bodies sell to an audience that it covets. That audience being the oval centric people that stand up and cheer when the see smoke, crumbled cars and rescue teams scrambling.

The flying cars are no doubt unintentional, yet, they may add a bonus to the sport if you have a demented mind. I wouldn't put it past the IRL.

[Methanolandbrats]

You are right, of course. It just makes me wanna puke. Most of the time you can get away with that carnage and mayhem crap in cabs, but open wheel is a different ballgame. I just pray that somehow, someway that ******* in Indiana is stopped before this insanity goes to the next level.

[racer2c]

Spot on T7, spot on.

[ChrisB]

Accipiter (Ron Payne) started a good thread on ras.indy here (http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=Ldnmb.21895%24Tr4.46417%40attbi_s03&rnum=1&prev=/groups%3Fas_q%3D%26num%3D10%26as_scoring%3Dd%26hl% 3Den%26ie%3DUTF-8%26oe%3DUTF-8%26btnG%3DGoogle%2BSearch%26as_epq%3Dlarger%2Bsid epods%26as_oq%3D%26as_eq%3D%26as_ugroup%3D*indy*%2 6as_usubject%3D%26as_uauthors%3D%26as_umsgid%3D%26 lr%3D%26as_drrb%3Dq%26as_qdr%3D%26as_mind%3D12%26a s_minm%3D5%26as_miny%3D1981%26as_maxd%3D25%26as_ma xm%3D10%26as_maxy%3D2003%26safe%3Dimages) which dicusses the larger sidepods needed for oval racing may be a cause of providing more "lift" because of more surface area underneath.

Also, is part of the problem the high-downforce mandated/minimum wing angles? ...and what is the reason for the mandated/minimum wing angles in the first place?

RACER did an article on IRL safety issues a few years back (12/97?) and mentioned the problem of the airbox taking away air from the rear wings during even very small oversteer (see image below) thus reducing grip and making the breakaway worse. The article also mentioned that they implemented the wing angle thing after they found out about the airbox problem, which kinda implies they want a lot of downforce to prevent the car from oversteeering at all in the first place to minimize the problem.

This was part of the reason some of us were saying... back when CART was considering going to an IRL variant chassis in late 2001... that they shouldn't use airboxes. I mean, why does the IRL use an airbox at all? Some say it's for more sponsor space, or differentiation from Champcars. My contention is.. why use something that makes the car unstable for the sake of increasing engine power when you only have to dial the powert back with the rev-limiter later?


http://www.netaxs.com/~gg1/race/airbox1.jpg

[Railbird]

there are no mandated wing angles at Indy, the only place the IRL races without them.

That will be the "fix" they use.

[nrc]

Trouble is that they get airbourne backwards as well. A fixed rear wing angle may only make that problem worse unless they take other steps or cut speeds drastically. Contrary to the arguments of those who say that this problem has been exaggerated, it may be underestimated.

Someone should go through every accident in the IRL these season and last and count the number of times they've had wheels off ground for some reason other than contact. I distinctly recall SpeedNews highlights of IRL cars having their rear wheels off the ground before backing into the wall.

In fact, I would go so far as to suggest that this is not a new problem at all. It's just that it has reached a tipping point because of the new chasis, new engines and the speeds they're creating.

[FRANKY]

Originally posted by nrc
Trouble is that they get airbourne backwards as well. A fixed rear wing angle may only make that problem worse unless they take other steps or cut speeds drastically. Contrary to the arguments of those who say that this problem has been exaggerated, it may be underestimated.

Someone should go through every accident in the IRL these season and last and count the number of times they've had wheels off ground for some reason other than contact. I distinctly recall SpeedNews highlights of IRL cars having their rear wheels off the ground before backing into the wall.

In fact, I would go so far as to suggest that this is not a new problem at all. It's just that it has reached a tipping point because of the new chasis, new engines and the speeds they're creating.

Foyt IV was moving pretty quickly backwards and it didn't blow over.

They need to Test Test Test Test Test Test and come up wuth an answer. The damn problem us that no two accidents were alike, but what should be noted and EXAMINED is that all the accidents end the same way, flying through the air seemingly at record heights.

[racer2c]

Originally posted by FRANKY
Foyt IV was moving pretty quickly backwards and it didn't blow over.

They need to Test Test Test Test Test Test and come up wuth an answer. The damn problem us that no two accidents were alike, but what should be noted and EXAMINED is that all the accidents end the same way, flying through the air seemingly at record heights.

True. Imagine, they might actually end up with a real race car.

[JT265]

Railbird is right, Indy is the only track that doesn't use the mandated wing angle.

How about this. Many teams find that running a negative chassis rake helps to get the rear wing outta the airflow, but depending on the size of the venturi underneath the pods, this would give the car the same kinda attitude that a powerboat has just before it planes out. So, if you have a 3" RH at the front, and 2 3/4" at the rear, coupled with the wide plane of the front wings trimmed out to almost nothing, isn't this just kinda asking for trouble?

[JoeBob]

Originally posted by ChrisB
My contention is.. why use something that makes the car unstable for the sake of increasing engine power when you only have to dial the powert back with the rev-limiter later?

Prior to the Renna accident, word was already spreading that for 2004, the IRL would be adding openings in the engine cowl, and making major revisions to the undertray.

So... not even going to be using the airbox to increse engine power!

Hopefully, part of the goal of the new undertray development work was to keep the cars on the ground. (I wonder if something similar to NASCAR's roof flaps could be incorporated into the undertray. There's a bunch of empty space in the sidepods, let them open up into there. (And, if need be, add corresponding flaps to the top of the sidepods, to let the air out of there.)

[cart7]

Originally posted by JT265
Railbird is right, Indy is the only track that doesn't use the mandated wing angle.

How about this. Many teams find that running a negative chassis rake helps to get the rear wing outta the airflow, but depending on the size of the venturi underneath the pods, this would give the car the same kinda attitude that a powerboat has just before it planes out. So, if you have a 3" RH at the front, and 2 3/4" at the rear, coupled with the wide plane of the front wings trimmed out to almost nothing, isn't this just kinda asking for trouble?
Thanks for saving me the typing JT, I was gonna ask this same thing.

There's definitly something wrong here. Yes, Mario got a piece of debris under his car before he launched. Wheldon's undercarriage got under his car when he launched, although, he was traveling at a relatively slow speed when he did. Helios was a wheel on wheel deal. Kenny's was a wheel on car deal though I don't believe that completely after viewing the head on shot a couple times in slo mo. Now, Renna bites the big one having a normal racing situation where the car got out of shape after him making a mistake in T3.

The underlying problem here is these were all racing deals that can happen at any track. There shouldn't be a situation where a normal racing incident has the potential to launch a car into the air and ultimately into the spectator seating areas.

I wonder if the changes in weight reduction (about 25lbs I've read) and changes in the chassis have now put these cars on the edge of flight in any given situation?

[Napoleon]

Originally posted by ChrisB
...and what is the reason for the mandated/minimum wing angles in the first place?

IMO, the reason is a variation of the Peter Pricple. By mandating wing angles they can dumb the spec. down to the level of the most incompetent drivers they have in the series, like Foyt, Carpenter and Fisher so that they don’t all end up in the wall in the first lap because they try to trim the car out like a driver like DeFerran may be able to, or end up 25 laps down because they have all kinds of wing dialed in while some of the non-wankers do not.


Originally posted by ChrisB
I mean, why does the IRL use an airbox at all? Some say it's for more sponsor space, or differentiation from Champcars.

Just some more garnishment TG had added to the car to make people think the IRL was intended to be something different from CART. Just another chapter in auto racings own Potemkin Village, the IRL.


Originally posted by nrc
In fact, I would go so far as to suggest that this is not a new problem at all. It's just that it has reached a tipping point because of the new chasis, new engines and the speeds they're creating.

I think you are right. I would call this the “Texas Effect” after CARTs test at Texas that went OK, but when qualifying speeds were quicker a few months later it was, apparently, enough to make the difference.

[Accipiter]

Thanks to Chris for pointing me to this forum and thread.

There I things I have heard that I wonder if anyone can confirm. Have the wings been enlarged this season compared to last? And has the Venturi size been reduced?

If those are both true, added with the larger sidepods, it sounds like a perfect recepie for causing flight. I can see what their thinking would be for making the changes, and it all sounds on the face reasonable. If you take away undertray downforce, you force the teams to get it back by putting more wing angle in the cars, and that causes drag that slows them down. And if you put on bigger wings, you create more drag. And extending the sidepods forward, that has been both attributed to trying to prevent wheel to wheel contact, and better lateral crash protection. But if you add them all together, what you get is more surface area under the car, and less useable downforce for when the front wing loses effectiveness due to improper angle of attack (from hitting a car, debris, bump etc.).

Like the airbox oversteer problem that Chris pointed out above, this appears to be another dangerous unintened consequence of rule changes that the IRL has become notorious for.

And speaking of that problem, I believe one of the ways they solved it was raising the rear wings on the original spec cars in '98 or '99.

[DaveL]

Originally posted by Napoleon
IMO, the reason is a variation of the Peter Pricple. By mandating wing angles they can dumb the spec. down to the level of the most incompetent drivers they have in the series, like Foyt, Carpenter and Fisher so that they don’t all end up in the wall in the first lap because they try to trim the car out like a driver like DeFerran may be able to, or end up 25 laps down because they have all kinds of wing dialed in while some of the non-wankers do not.


The other piece of that is the mandated wing angles create tons of drag so the cars are slowed down. The reality is than an IRL car is way overdesigned for the type of racing it is doing so they have to slap rev-limiters on the engines and put DC-3 wings on at near stall angles to keep them from going too fast for human physiology to cope with.

[Peter Venkman]

"I wouldn't put it past the IRL."

Absolutely.

[JoeBob]

Here's the closest I could find to the announcement of the spec changes. Clearly, it isn't a complete list. (It makes no mention of using two element rear wings everywhere but Indy, so other aero tweaks may have been left out as well.)

http://www.racinglines.com/article/articleview/2071/1/7/


Barnhart noted the overall appearance and aerodynamics of the new cars will be consistent with the current 2000-2002 package. The following are changes in the 2003 chassis that will enhance driver safety:
*The distance between the pedal bulkhead and front bulkhead will be increased by a minimum of 3 inches, moving the driver back.
*Side pods must maintain a minimum width of 60 inches along a greater distance.
*Energy-absorbent materials will be introduced for driver leg protection.
*Front suspension mounting points must have a bulkhead directly behind them.
*Aluminum honeycomb core used in chassis construction must conform to a minimum core density.
*Car weight will be reduced to lessen impact mass.
*A minimum chassis length will be established. In another driver-related safety requirement in 2003, the driver must be able to undo the safety belts, remove the steering wheel and exit the car in less than five seconds. Chassis designs built for the 2003 season will also undergo rigorous impact and load tests that will meet or exceed FIA standards. The Indy Racing League has specified the following changes in those mandatory tests:
*Increase side load on nose push-off test.
*Increase energy on first nose impact test.
*Increase energy on second nose impact test.
*Chassis must not incur damage during nose impact tests.
*Increase applied load during roll hoop test.
*Increase side intrusion absorbsion levels.
*Introduce impact test and side load test on new rear crash structure.