anyone know what height he had his wing at? I was looking at the AOA of his APR wing and it seems like he was pretty aggressive with the AOA. Perhaps excessive downforce over time made the wing give way eventually?

Regardless, this might be worrying issue for APR users who track extensively.

 

I think for this event they had tried raising the wing above the roof line to see if it would help out and that is when it became too unstable I guess for the wing to hold on. Maybe it needed cables to support it or something.

 

Wow, that's crazy. Glad the driver was able to walk away.

I have the APR GT200 and I just installed the 2.5" riser. The screws that bolts the riser to the main stand seems kinda short. It only thread in about 1/4". I was going to get longer screws or make a custom one piece stand that's the same height as the extended stand. This makes me want to take a second look at how the wing mounts to the trunk.

 

As some of you probably already know I converted the GTC-300 into an active aero wing. The wing failed on me at lightning in NJ. I am fairly certain it was my system and modified mounts that caused the wing to fail. However there were also high side winds (40mph) that most likely contributed. Here is a picture of my wings failure:



It's eerily similar to the element tuning failure. A lot of people had aero problems at lightning (3 broken wings) none of the other failures were APR parts. The solution that everyone came up with was to make an x brace between the two mounts out of thin steel cable giving the wing significant lateral support.

Definitely something to consider.

 

I am glad that nobody was hurt in these accidents! I tend to agree with the lateral load statements on the wing; the failures at that point on the mount could only have been caused by a bending fatigue on the carbon mounts. If there was even a tiny little surface nick in that area, it would significantly weaken the carbon structure

 

I'll be at NJMP Lighting this weekend for NASA TT. I'll see if I can put some x brace cables for lateral supports.

 

Those mounting plates seem pretty thin for such a highly stressed component.

 

what I've learned from this video:
don't let element tuning doing any work on your car

 

The wing had more bending moments at the bracket/pylon interface. (M = F*D) since it was catching more air in the "cleaner" airstream above the car's roof. Then the pylons' mounting points on the trunk were stronger than the wing's, so it failed at the weakest part.

Depending on the angle of attack and airfoil design, some of these wings can probably see 200 lbs of force, perhaps even more. You want to keep the angle of attack at no more than 12 degrees, anything more and you are just driving with an airbrake as the airstream just separates too soon.
Lateral loads exacerbate an already failure-prone condition, so if the wings were already near their limits of stress failure, the added side loads induced failures sooner. A lot of this wings are not really engineered. Many companies just make stuff without calculating how much material/fasteners their parts need in order to keep them from failing. It's more costly to have a high-salaried engineer calculating cross-sectional stresses or doing FEA on parts.
Most applications do not fail and last a lifetime simply because most people mount the wings low on the trunk so they never see much clean air and don't generate a lot of forces. This is a good example showing a part that is marketed to be for "racing" but clearly it is not.

Phil, the driver, has quite a lot of track experience and has participated in many time attack events. He is actually one of the best tuners I know. he worked for TurboXS back in the day and helped developed the 1st standalone ECU - HydraEMS, for drive-by-wire Subaru STI's back in 2004. The steering inputs that may look excessive to some, may be due to the AWD drivetrain. Different animal compared to our more refined handling in the S2000. I own both, and I find myself having to drive the S with smoother input.

The HANS is at its best in front/rear collisions, but it also helps restrain your noggin on side movement. The straps limit excessive sideways motions as well. Even if you crash backwards, your noggin will rebound forward with a lot of momentum. The HANS also helps in that situation.

Well, hopefully everyone who uses these wings benefits from mishaps like this through inspecting/ reconsidering their setups

 

downforce don't cause it to fail, no matter how weak that structure is. GTC wings has been used in RACING, in Koni Challenge and others. there is some engineering inputs on this over at Trackhq. it is mounting fail, not parts fail.

read Momentum's post. there are other aero wing failure, not GTC.

just to throw it out there. let's say he forgot to tighten the nuts below one of the wing mount. doesn't drag (tearing off the wing) will cause same type of failure ?