RallyCross rollover risk?

From time to time I've heard people talk about seeing this or that car rollover at rallyCross events. At last weekend's event I realized after a while that I was very tense and driving conservatively because of that anxiety about sliding sideways over an unpredictable surface.

I kinda talked myself out of it, but I like to be reasonable. What exactly IS the level of risk (driving either an '01 Outback or '05 9-2x) and what can be done to further mitigate that risk <<EDIT: mitigate risk OF INJURY, that is>>? I don't mind some risk, I get that it comes with the territory, but want to understand what I'm dealing with. 

In reply to P3PPY :

I've been wondering about this too. A couple guys at the events I've seen mentioned upping the air in their tires so they don't break the bead. But the surface here is quite smooth and is a "pea gravel" parking lot. So I don't think our surface would tend to be the cause of  roll over.

I've seen a couple roll-overs and apparently got somewhat close to a roll-over once, myself.  As I recall, one of those events was due to a suspension part breaking and digging in.  My understanding is that the others I've seen were due to some nasty course conditions not getting corrected and cars getting caught out by some ruts in the dirt.  I suspect Pete will chime in with more details because I think he knows quite a bit more about the circumstances with those than I.

Debeading is definitely something to be concerned about, but even when I've debeaded a tire, I haven't felt like the car was unstable in a way that would lead to rolling over. 

I was one of the organizers for local rallycross in Vegas from around 1998 till 2007 and we had one actual roll over and one that came very close. 

The actual rollover was a Tacoma pick up that the person had just purchased; the driver hooked a deep rut and that levered the truck over.

 The near rollover was an SUV and the same scenario.

We ran on dry lake beds and those rut up.

I have an 11 Outback that I've used as rally support vehicle and I wouldn't have an issue rally crossing it but I would air up the tires as they are tall and I could see the possibility of debeading one going from a loose to grippy surface.

Most of the rollovers I have witnessed have been at very low speeds, mainly with higher profile cars (fiesta etc) on stock suspension. They set into a rut on a sweeper and flop over. The more dramatic ones have been mainly a result of parts breaking and the car digging in. 

The only times I have debeaded are on rally tires when I forget to top one off that I know is leaking. I have only debeaded on the rear but the only thing I have noticed is that handling gets a little funny. 

I don't think about it at all while driving. If you want to mitigate the risk of injury you could look into 4 or 5 point harnesses or maybe a CG lock style device to keep you firmly in the seat. 

Edit: Also most (maybe all) rollovers that I have personally witnessed have been at national level events. Whether it is people pushing harder than they normally would at local events, much higher number of cars on the site causing ruts to form faster, more cars to run through an iffy section before making a course change or some other reason. 

I've personally done about 100 rallycrosses over 10 years and seen 4 total rollovers:

One was a very aggressive, top-tier Mod FWD driver who just hit a rutted corner too hard coming from a fast section into a heavy braking area turn. 

One was a tippy, short-wheelbase Hyundai that basically soft-rolled because the driver got on the wrong side of an outside berm on a 180* turnaround (minimal damage)

One was a broken (auto part store) tie rod end on a fast overpowered FWD car in a very fast transition section

One was a short-wheelbase stage rally car driven really badly that may or may not have had a debead (soft roll, minor damage)

All were FWD, for what it's worth. 

In those 100 events, where I'm typically one of the top 5-10 fastest drivers, I've never myself come close to a rollover, that I can recall. All in all, I've never really considered it to be a particular concern, especially in RWD cars.  I've never debeaded in 10 years of doing this :)

irish44j (Forum Supporter) said:

 

One was a broken (auto part store) tie rod end on a fast overpowered FWD car in a very fast transition section

 

Factory Honda part just the dinky EP3/Base RSX/CRV version not the heavier duty RSX-S version. Who knew a 3ft long M14 threaded rod was the wrong choice for a tie rod. 

But fast and overpowered are my two favorite words to describe that car. Maybe the turbo was a little too big... Thankfully we have a lighter more intentional AWD car to attach it to now. 

Lots of racing over my life upside down in an ITA neon once and in the above mentioned EP3 at a rallycross. Both bad place bad time to have a mechanical failure deals.   

In any form of motorsport but more so in rallycross you are in control of the outcome, if you push to 10/10 every time eventually the course or the car will bite you. The guys who hang around 8/10 with a little left in the traction ciricle for sudden unintened course changes are generally faster. 

For anyone who has witnessed this in a car with stock safety equipment, how did it turn out for the driver? Airbags on or off?

And FWIW, I debeaded the Outback this last time. And as EvanB commented, I didn't really notice it either until we got in a straight. I did two decent corners with it like that. It's not that I didn't hear a noise, I just thought we were losing the rearend, and since the owner in the passenger seat didn't care, I didn't care. 

P3PPY said:

For anyone who has witnessed this in a car with stock safety equipment, how did it turn out for the driver? Airbags on or off?

 

I've seen a few with airbags that went off (don't know if the others had airbags still in place). None of the ones I have seen (maybe 6-7?) resulted in any injuries to the driver. 

I've seen 3 roll over at my local rallyx at speeds no greater than 40 mph.  It doesn't take all that much to roll a car.

A genuine 40mph feels very fast on course.  You're generally not going to have a corner tight enough to trip the car at those speeds.

Done a couple dozen rallycross events, all in a Volvo Amazon. I've had bystanders claim I was scraping the door handles, but I've never felt close to rolling over. I e seen maybe 1 or 2 actual rollovers, so out of probably over 400 or so cars entered across all the events I've been in, less than 1/2 of one percent have rolled. 

EvanB said:

Edit: Also most (maybe all) rollovers that I have personally witnessed have been at national level events. Whether it is people pushing harder than they normally would at local events, much higher number of cars on the site causing ruts to form faster, more cars to run through an iffy section before making a course change or some other reason. 

I did rallycross from 2011 -2017 or 8 and the only rollovers I witnessed were all at Nationals in 2014.  I blamed it mostly on the site deteriorating and rather than shift the course a little to avoid the ruts they kept trying to fix it with farm equipment.  And our Ohio sites tended to rut pretty good but maybe saw a few on 2 wheels a bit.

When I rallycrossed the Jeep, I was always careful to avoid sliding it across ruts, especially on one hilly site that had a few slightly off camber spots.  But other than that, I never worried much about it.  On the sites I ran, pretty much any other rollover would have been caused by a collosal mistake first that put the car well off course and into something that could trigger a roll.  There was only 1 rollover in the region that I know of in the years I was around, and it was definitely preceeded by a big screwup. 

Even when I set the day's speed record through a slalom (pretty sure I saw the speedo crack 60) after the snow melted one day and (not realizing quite how fast I was going until I glanced down as I lifted) got some horrendous lift throttle oversteer when I went to slow down, getting sideways on whatever packed dirt / gravel / etc. mix that site had wasn't all that sketchy.  I was far more concerned about not going off course far enough to clip a tree, and getting it slowed down before I hit the turn-around at the end of the slalom (I did punt a cone with a rear fender, but didn't go far enough to make the course worker there run).  Rolling it wasn't really a concern, even in a full opposite lock slide at higher than typical rallycross speeds. 

Only reason I stopped running the Jeep were life getting in the way and the Jeep needing a bunch of work.  Safety-wise, it was fine, just a bit uncompetitive (in more open sections of a course it could put down power well and had lots of grip, but as it was configured at the time, getting it through the tight sections of a course was not exactly fast). 

EvanB said:

P3PPY said:

For anyone who has witnessed this in a car with stock safety equipment, how did it turn out for the driver? Airbags on or off?

I've seen a few with airbags that went off (don't know if the others had airbags still in place). None of the ones I have seen (maybe 6-7?) resulted in any injuries to the driver. 

Heck, I've seen several GM products blow the airbags on an autocross course, without so much as hitting a cone.

EvanB said:

P3PPY said:

For anyone who has witnessed this in a car with stock safety equipment, how did it turn out for the driver? Airbags on or off?

 

I've seen a few with airbags that went off (don't know if the others had airbags still in place). None of the ones I have seen (maybe 6-7?) resulted in any injuries to the driver. 

I think 90% of the cars at our rallycrosses are pre-airbag anyhow lol.

I also see a roll per 15-20 scca events not counting side by sides and not counting rallycross nationals.

An average rallycross roll is a slow rotation on to the drivers a-pillar.  You need to decide if your a-pillar will support the weight of the car when it comes to rest on the roof.

A 3 point seatbelt will let your body move down and to the middle of the car during a roll. The downside is a higher chance for a secondary injury.  A 4+ point will keep you in place which lowers the chance of a secondary injury.  If the a-pillar collapses, your neck could become a structural support for the vehicle since your body is held up by the harness. 

My car's safety cell was designed around 1990 and I prefer a broken arm to a broken neck.  The 4 point makes more sense in a more modern subaru with a few extra inches of headroom or any car with a proper rollbar.

I've been rallycrossing since 2012 and have witnessed two rollovers and personally rolled one car. 

Personal roll - '96 Ford Econobox GT, completely gutted and only glass was the windshield, so it was sitting rather high.  High speed sweeper into a tight opposite corner.  I scandanaian flicked it and had just a hair too much sideways momentum when I hit the fluff berm.  Very low speed rollover, I was fine and the car could have still been raced, had it not cracked the plastic end tank on the radiator.

'16 Nationals - base Ford Fiesta.  This one was rather unusual, as there was absolutely no rut.  The area was very grippy clay.  the driver counter-steered the roll and rode on two wheels for a long ways before it finally went over.  This one deployed air bags, which did more damage than the actual roll. I'd say it was the high height to track width that did this one.

Lifted Mini Cooper S - please don't lift these, they WILL roll on rallycross.  For about a year or so, lifted Mini Coopers seemed to be the defacto car to race in Milwaukee Region. They rolled at least three of them, one twice I believe.  The one I witnessed basically pirouetted on nose and landed on its wheels.  Headlights were smashed and the hood crumped, but no other damage.

Someone on the RXB once told me that the entire SCCA program averages 3 rollovers a year, so that is a pretty minimal percentage of the overall.

OK, so the overall roll over risk seems to be minimal particularly for a vehicle that is not “tall”.

The debead risk seems to be more possible than roll over, to some extent. To prevent that folks air up their tires. My question being – how much. Is there a rule of thumb, or a calculation, or???

In reply to FooBag (Forum Supporter) :

Any idea what made the minis so prone to roll? The track width is two inches wider than the height.  That isn't great but is better than a Fiesta ST.  I have seen lift kits where you put stock shocks on a spacer and I bet they aren't helping.

L5wolvesf said:

The debead risk seems to be more possible than roll over, to some extent. To prevent that folks air up their tires. My question being – how much. Is there a rule of thumb, or a calculation, or???

It will vary based on the car or course but the general rule for snow tires is around 40 psi. 

EvanB said:

L5wolvesf said:

The debead risk seems to be more possible than roll over, to some extent. To prevent that folks air up their tires. My question being – how much. Is there a rule of thumb, or a calculation, or???

It will vary based on the car or course but the general rule for snow tires is around 40 psi. 

Our course wasn't even that crazy (what do I know, I've done rX only twice), but apparently for an older Outback on stock rims and snow tires, it should be more than 37 psi. 
40 checks out. 

ojannen said:

In reply to FooBag (Forum Supporter) :

Any idea what made the minis so prone to roll? The track width is two inches wider than the height.  That isn't great but is better than a Fiesta ST.  I have seen lift kits where you put stock shocks on a spacer and I bet they aren't helping.

I'm guessing with a lift it had taller tires as well which would make it pretty unfavorable from a physics standpoint.

I am 0% surprised a Fiesta rolled though.

EvanB said:

L5wolvesf said:

The debead risk seems to be more possible than roll over, to some extent. To prevent that folks air up their tires. My question being – how much. Is there a rule of thumb, or a calculation, or???

It will vary based on the car or course but the general rule for snow tires is around 40 psi. 

Would 40 apply to all season tire too? This coming weekend will be my first rallyX. My tire’s recommended pressure is 32 (51 max) for current size 205 60 15. Assuming I do well and like it I will likely get a set of tires specifically for rallyX.

My tire shop loves to have every tire at maximum pressure just because. They have reasons so I run with it. No damage so far, seems like no reason not to for rallyX, right?