Chads996

Time Attack prepared Suby STI loses its rear wing at 148mph at VIR. Looks like the wing struts failed (made of CF) at speed. Overall, the driver compartment held up very well after that hit.

Ouch. CODE BROWN.



Aftermath pics...






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paradisenb

Damn!!! that car looks surprisingly good after a 148mph hit. Glad to see the driver climb right out.

fhp911

According to the video, the wing broke off quite a while before the crash -- so was the crash due to the loss of aero or in some way from the falling off of the wing? (presumably loss of aero.)

Chads996

Quote from the driver...

"With the new engine tuned we headed off to the second round of the NASA season at Virginia International Raceway. One of the major changes we made to the chassis was to have taller wing supports made so we could get the rear APR wing up into clean air in hopes of gaining down force. We also had added a rear diffuser to the flat panel underneath the car. After running at minimum power for practice and scrubbing in new tires the car felt great and the power delivery was awesome.
As we headed out for time session one disaster struck on the first lap! I was taking it easy to get the tires up to temperature but as I exited turn 6-7 the carbon wing structurally failed between the air foil and the mount. Not knowing this I entered the uphill esses at around 148 mph and this is what happened."

C.

Gary R.

So he was "taking it easy" at 148 MPH? What's pushing it, when we hear a sonic boom in the video?

Bryan Watts

That's because he wasn't doing 148. The Riley track day car (i.e. Daytona Prototype with more power and better aero) is only doing 140 at that point on track while running 1:44 laptimes as shown with data over on Bimmerforums. 600 hp and 2000 pounds. If he was doing 148 at that point on track, he would be significantly faster than the 1:59's he has run. I run 1:58's while only doing 130ish at that point on track.

But I digress...hell of a crash and really lucky to be unhurt. Can't help but believe that the wing was covering up some other sort of problem to cause such snap oversteer at that point on track. So, this video shows both the importance of aero as well as the potential importance of not letting aero potentially cover up any setup problems.

SundayDriver

If it was setup well, with aero, I would expect it to have quite a bit of mechanical oversteer (for the slow stuff) and use the aero to manage that at higher speeds. That is how I have always set up aero cars. So, the loss of the rear wing would make it snap pretty badly. So, not covering up a problem, rather controlling an intentional setup that would suck without aero.

RJFabCab

Ditto that on the 148. I watched the video and thought there's no way he's doing 148 into the esses.

Really good to see him walk away in a prepped car with safety gear. Friggin' steering wheel busted... and he let go prior to impact.

So, he lost the wing coming out of snake? Straight line he was 'fine' on throttle... a little left prior to 7... SCARY!

analogmike

right, his speeds listed were pure BS. Bud really sad that it happened.

mark kibort

That is ugly. after building yet another race car, I feel the pain. Its not the money, its the time!!
(unless its not you time, and just the money)

You dont need much strength on the pull back force on the wing, as its generally about 1/10th of the downforce, but at 148 ( ) or 135 , there still is some rearward, downward force and the struts have to be up to the task. often, folks dont really build up the wings to handle the real forces when the speeds get beyond 120mph. I like that picture of that one dude that laid down on his wing to prove it was strong .

JackOlsen

I static tested my home-made uprights and wing with 350# of sand. But that's less than the wing theoretically generates at top speed, and it's a nice smooth load compared to a car going over an uneven surface in buffeting air.

Bryan Watts

Agreed on an "aero" car, but not on a street sedan (i.e. no flat bottom, diffuser, etc) with just a single element wing and splitter attached to it. I just wouldn't expect the oversteer to be so sudden at that point on track if it was only a lack of the wing that caused the oversteer.

JackOlsen

Actually, I think it did have some form of 'diffuser.'

To me, that's scary on a production car when you're hitting 148 (or 128, whatever) on any kind of regular basis. Without a super stiff suspension, I think you're asking for trouble with anything approximating ground effects that you can't hold in a very consistent position relative to the driving surface.

IcemanG17

WOW....glad to see he walked away.....

kurt M

I did something along the same lines with mine. It held the weight as hoped. I have noted a lot of the taller wings have too much side to side movement and I added cables from the end plates the base to triangulate the wing. You can rock the car by pushing on the wing. I did not want to have the wing flop down sideways in a high speed corner and have the back go light.

It looks like the EVO put the drivers wheels over the gator at the apex and this started the back end stepping out.