Could this be a problem?

[dubby99]

I was just thinking about this the other day about how the downforce is made on the new DP01. Alot of the downforce comes from the underside of the car which is good in terms of cleaner air behind the car which should allow for close racing.

But here is the thing thats getting me worried, if a car at high speed climbs up on the back of another car and the front end of the car gets air would the effects of the underwing be reduced from the increase in ground clearence?

Could this cause the cars to take off?

You also have to remember that the wheel base is much shorter due to the fact that front wheels have been moved back to increase the effect (leverage) of the downforce on the front wheels without increasing drag, and as far as i know the front wing does not produce the same amount of downforce as the Lolas.

Is it just me or is there potential for a bit of a disaster?

We have seen that when an IRL car gets air underneath the front end it takes off as seen with Mario Andretti back at Indy and i think even Sam Hornish got some air too. I think there has been more cases but i really don't watch the IRL.

I am very sure Panoz would of thought of this when they design any of there race cars, but i just don't want to see anyone get hurt such as the track workers or fans and even the drivers.

[blueflagger]

Darn good question. I've no idea about the correct answer and I'd hate to be the driver who finds out.

[macdaddy]

...if a car at high speed climbs up on the back of another car and the front end of the car gets air would the effects of the underwing be reduced from the increase in ground clearence?

Could this cause the cars to take off?

The effects of the underwing would obviously be lost outright. This has always been the case, so I see no more danger with the Panoz than with its predecesors. If the front end of a Lola was lifted, it too would lose all downforce. Even the effects of its front and rear wings would be nullified. And so, although I'm far from expert, I'd suggest that the risks are no higher than they have been.

[racerkeke]

We almost had a "blow-over" (hydroplane talk) of exactly this type with Indy Lights on the backstretch at Michigan. Borkowski was the driver of the flying car if you remember him. The only reason he didn't lift off and flip backward was that he hit one of the bars that hold the yellow lights on the fence on his way up, which thumped him back down. Most amazing thing I've ever seen -- he could have done this at any point on the track and not hit a light. Just luck. Of course, given the tight pack, he took out at least three other cars even though he didn't blow over. So I think it's possible in any open-wheel car, given the right conditions.

keke

[blueflagger]

Macdaddy, I can see where it would lose the downforce on the bottom of the car if the front end lifts, but I'm thinking there might just still be enough downforce on the rear wing to flip the car backwards. If so, it would happen very early in the incident when the car would be still carrying a whole lot of energy to disperse.

Kinda like a Mercedes at LeMan? Or powerboat racing? (RaceGypsy's comment).

Ow, ow, ow!

[Woolley]

Just about any lightweight winged car (include sportscars, single seaters, dragsters, sports boats) with a large-ish underbody area is prone to flipping over if the air gets underneath and I've seen it on a number of classes, including F3. I don't know enough about aerodynamics to know whether this is because of the air underneath pushing upwards or because the increased angle of attack turns the upper surfaces into a wing, or both, but if you're travelling forwards at speed with your front significantly in the air for whatever reason, there's a strong chance you're going to turn over unless the front of the car has sufficient weight to counteract it.

Having said all that, there's a possibility that the underwing might still produce enough suck to bring it back down again (or stop it going up in the first place), whereas a flat bottomed car won't. Perhaps someone with better knowledge of the subject can tell me if that thought has any merit whatsoever?

[Snrub]

Remember in 2005 when PT ran so quickly in Toronto essentially without the front wing? Clearly the vast majority of downforce is generated by the venturi rather than the wings.

Keep in mind that there are no ovals left in the series so the top speeds will be lower from the IRL situations.

[luke]

Originally Posted by Snrub

Remember in 2005 when PT ran so quickly in Toronto essentially without the front wing? Clearly the vast majority of downforce is generated by the venturi rather than the wings.

That's a great point Snrub. Tracy seemed to have very little disadvantage when he was leading was it? At Toronto...

[Knowlesy]

He was running away with it until he ran out of fuel.

[luke]

Oh yes I remember, he and Seb collided on the exit of pit lane...

[paul-collins]

Even flat bodied cars are very dependent on undercar aero now, with the low ride heights they use - cf the Mercedes flip at Le Mans. Catastrophic loss of downforce is always a problem. I don't know whether there's more sensitivity to this with tunnels or not, but I'd guess not.

IRL had problems for a while because of this IIRC - with a fixed rear wing pitch angle, the only way to trim out the drag was to lean the whole car back, which led to the underside of the car being closer to the point at which the undercar downforce would disappear. I think the regs have been changed to avoid this running configuration now.

ACO sportscars now have an underbody shape a bit like a boat, with a keel, so that even at the lowest permissable ride heights the underbody downforce generated is from underbodywork that's a fair bit away from the ground, and less sensitive to changes in height. With more bodywork to generate top-of-car downforce, though, I think they're less sensitive to the dirty air that affects the wings on formula cars.