Massive Shadow DN4 wreck at Road America

[ACCP]

https://youtu.be/9t-iPMsHXyM

Driver was OK. Looks similar to the myriad late-90s blowovers. Some talk in other areas that maybe it's time to retire these types of cars from active competition since this appears to be the 3rd crash of this type for Can-Am cars, specifically the Shadows, in the last 3 years. Would hate to lose the chance to see them in person but by the same token that wreck would be terrifying in a modern prototype, let alone a 45 year old aluminum can.

[Truth Detector]

Scary crash. Glad to hear the driver is okay. I'm sure there have been others but it reminds me of the Mercedes crash at Road Atlanta. IIRC that was also the trailing car. Can somebody smarter than me explain why?

[SteveK51]

A car gets light when cresting a hill. Just like in regular old drafting, the leading car creates a low pressure area behind it, which the trailing car is in. So the trailing car, in the low pressure, has decreased downforce on the front, in a condition where the weight of the car is doing less to hold the car to the track due to the track's geometry. And also the rear wing is far enough back and high that it's getting decently undisturbed air. So the front goes light, the rear stays planted, and the car pivots the nose up.

[Truth Detector]

Thanks.

[Automotive]

There is video out there on u tube. Pretty devastating and comprehensive wreck. Driver is fortunate.

[Sweaty Teddy]

Ironically one of the cars had a big front wing on it at some point during the week that the team used at Road America just for this reason.

IMG_1393.JPG

The driver who shared this picture noted before hearing about the incident that he watched at least one of the DN4s getting lift on the front straight during practice prior to the incident. I don't think either Shadow was so equipped during qualifying.

[dalz]

Holy smokes it was veteran sports car driver Jim Pace. A story intimates that the roll bar got used and it was up to the job. It was the perfect set of conditions--a high-speed large car with poor aero, just cresting a hill, downforce compromised by a big tow.

Racers are gonna race. A prominent amateur Chicagoland racer lost his life in a Can-Am car at Mosport a few years ago. Just check out the pre-war class races at Goodwood with drivers trying to win at 10/10ths.

[Gurney36]

Pace's statement on the Vintage Motorsport site:

“I thank everyone for the genuine concern over my incident at the WIC this past weekend.

“The DN4 Shadow has always been a beast of a car — though it’s sweet to drive with its impressive acceleration from 1000 hp — and obviously aerodynamics play a major role in its stability. On Saturday, the conditions were just right — head wind, car speed, acceleration and drafting — that a little air got under the front and it lifted off. It actually lifted well before the crest, maybe even halfway up the hill. And as you know from the video, it went up and over!

“I thought about Charlie Kemp in a 917 at Atlanta and John Morton at Lime Rock as I began to see blue sky. I held the wheel until it landed upside down, then turned the master off as it slid and spun down the straight. Whatever happened would be better with the switches off. It kept sliding. Once it stopped, I unbuckled and rolled out from under it. I saw two crew members that I have worked with for years, one with a fire extinguisher, and I was grateful for them being there so quickly. That is a race crew — they charge into the danger zone to help the driver!

“I am fine. Not a scratch or bruise. I credit the form-fitted seat of SpeedSeats, the HANS device and the finest carbon fiber helmet for my safety, plus the guardian angels that watch over us all when we don’t know it. Thanks to Jim Bartel for letting me drive the Shadow and RM Motorsports for the excellent preparation of a fine vintage racecar.”

There are two interesting pictures on The Nostalgia Forum. One shows the DN4 leading Pace's with its' nose close to the ground while Pace's is beginning to lift, showing daylight underneath. The other photo shows the car post crash, on the hook, looking pretty good, considering:

https://forums.autosport.com/topic/65959-can-am/page-6

[Truth Detector]

That's a cool pic.

116108605_3326443314078429_570575974956967659_o.jpg?_nc_cat=101&_nc_sid=e3f864&_nc_ohc=_AEEMtNUH8kAX_KWtU4&_nc_ht=scontent-ort2-1.xx&oh=ff62a65b27e0c9c383b5f723d73b8b1e&oe=5F4987CB.jpg

[Frank Capua]

That's not a scary crash, this was a scary crash...

[DavidM]

That's not a scary crash, this was a scary crash...

That one's hard to beat! Lucky we didn't lose Chip or Lynn in that one!

[ensign14]

How difficult is it to film in landscape? Jeez.

[flatlander_48]

A car gets light when cresting a hill. Just like in regular old drafting, the leading car creates a low pressure area behind it, which the trailing car is in. So the trailing car, in the low pressure, has decreased downforce on the front, in a condition where the weight of the car is doing less to hold the car to the track due to the track's geometry. And also the rear wing is far enough back and high that it's getting decently undisturbed air. So the front goes light, the rear stays planted, and the car pivots the nose up.

The other thing that happens is the air gets packed under the front wheel wells and that contributes to the lift. That’s why IMSA and WEC prototypes now are mandated to have the wheel wells vented. The static weight distribution is also a contributor...

[flatlander_48]

That's not a scary crash, this was a scary crash...

That was a VERY expensive crash; probably approaching a $1,000,000 loss.

Many years later Lyn St. James was the Grand Marshall for the US Vintage GP weekend at Watkins Glen. I asked her what was it like the next time you got into a race car? Before she answered, she was quick to point out that the accident was due to Doc Bundy’s attempted pass (no argument from me!). Anyway, the next event was at Laguna Seca. She was there, I assume for PR functions, but she was not scheduled to drive. However, the team manager, whose name I don’t remember, suggested that she do some laps in the Probe GTP as a way to get back on the horse, so to speak. She agreed and got prepared. As she was exiting pit lane, she remembered trying to wipe the inside of the window. She then realized that that was exactly what she did after the crash, so mentally she had not left that point in time completely...

[Sweaty Teddy]

Here's a video from a session before the crash, complete with narration by JP.

What a beast of a car.