Speed Secrets: It's the Second Skid that Gets You
By Ross Bentley
September 10, 2014
In this week's feature article, Rob Schermerhorn writes about skid control, training, and the technology in modern cars designed to help those without the skill to help themselves. As you'll see, Rob covers a lot of material in one article, and I'm sure it'll make you think about your own skill development for track driving - and hopefully of those new drivers with whom you might have some influence. - Ross
There's a phenomenon going on in the world of performance driving and motorsport:
The competent, experienced driver has a big crash. Friends shake their heads in disbelief. "Bob had so many years of experience..." is what they say that day.
The fact is that "Bob" is, indeed, vastly experienced at his craft on the big tracks; what he's lacking is pure car-control skill - the ability to take skidding tires (already beyond maximum grip) and safely return them to a more tepid operating condition.
There's a similar phenomenon happening out on public roads: losing control of your car, though the driver had years of experience.
Completing a racing school, a performance driving school, or participating in a parking lot autocross event may contribute to crashing, because this new knowledge may instill false security; is three days in racing school enough training?
Do you have the skill to drive out of a skid?
There's a catch: the first skid doesn't typically get you, it's the second.
You lose control of your car during the second skid.
What's the "Second Skid?"
Brake lights suddenly appear where you don't expect them as the tail of the car in front of you kicks skyward; you swerve into the open lane, avoiding the rear-ender... but holy-+@^& - the back of your car slides out! Facing traffic after a quick 180, you're confused as to what happened, but relieved you didn't hit anything: you're a victim of the "second skid."
Nearly every driver is capable of successfully executing the first move: "swerve left!" However, it's not just that simple to move the wheel one time and survive; the momentum of the turning vehicle requires a second input:
1. Swerve to avoid obstacle
2. Steer back - beyond straight ahead - the other direction
It's this second steering maneuver that gets the driver who has never in their life practiced what a professional would call a "lane toss." A lane toss not only requires the initiation of steering, but also a large recovery steering movement to "catch" all the momentum that the mass of the vehicle has built up in one direction.
The "second skid" is where YOU LOSE CONTROL AND CRASH.
Without advanced driver training, specifically car control training (sliding around wet and dry skid pads, hourglass shapes, figure eights), the average driver has little chance to actively drive their way out of a skid. Our teenaged neighbor told me she was taught to "go with the car" in a skid, meaning "give up and let Isaac Newton take over" (or Jesus, if you're a Carrie Underwood fan).
Stability Control (call it ESP, ESC, DTC, DSC, Stabilitrac, or other manufacturer-specific acronym) exists to counter skidding. It has sensors and actuators, along with computer programing, to "sense" how you're driving the car.
- Steering wheel position
- Individual wheel speed
- Lateral acceleration
- Yaw rate
- Throttle position
- Individual brake actuation
- Possibly transmission control
Stability Control "catches" skids, countering them by intelligently actuating individual brakes (inside rear brake counters understeer, outside front brake counters oversteer). It compares steering position to yaw rate, quickly determining if you require "driver assistance" while cornering. Every manufacturer "tunes" their system differently, many offer an "Off" button (BTW, "off" doesn't really mean off for some manufacturers, including the 'ultimate' manufacturer).
Stability Control should not be confused with Traction Control, which is programmed and implemented differently.
Stability Control is so good at what it does (though it doesn't change the laws of physics. That's the dashboard button I'm waiting for...) that the NHTSA gathered the data, then drafted rules to mandate the technology by September 2011 in all road-legal production cars.
But Stability Control does not take the place of SKILL behind the wheel of a car; this fact is lost amongst our legislators, auto industry members, journalists, and the public at large!
Back in 2004, Chrysler launched their LX platform (300, Magnum, Charger) to acclaim by pundit and public alike. I was contracted as part of a vast traveling training team of pro drivers and facilitators for sales staff, management, and local media to learn what was so cool and unique about the cars so they, in turn, could share this information with the public as knowledgeable experts.
The LX platform was the first experience for most event staff (and all sales-staff participants) with a vehicle designed with Stability Control. (The car is awesome and I recommend you test drive one if you've never experienced a modern rear-wheel-drive vehicle).
We designed a drive course at each parking lot venue to show off the LX's fantastic dynamic abilities; one component was a skid pad of about sixty to ninety feet in diameter. Our fleet of Hemi-powered cars was wired to easily defeat the ESP system so we could dynamically show Stability Control in action while we (pro drivers) drove participants. The system is impressive, and while ESP is not the key to the LX's athleticism, ESP does improve safety. On the skid pad, one could drive full-throttle (or nearly so) without sliding for the bleachers in left field.
Amongst ourselves (not in public), we labeled the skid pad exercise the "circle of confidence" in that without advanced car control knowledge and training, your "average" driver will think he's impervious to error behind the wheel with Stability Control engaged.
It's so easy to see how Stability Control makes you feel like a hero behind the wheel as it succeeds in most instances in its intended goal: catch and correct skids, especially the "second skid."
Pure skid control takes practice to learn; only with practice will this skill become permanent, increasing your chances for survival in an emergency on the public roads, or driving out of a "big moment" on the race track without crashing.
Car Control anyone?
Many high performance drivers' schools incorporate skid control exercises, but it's just one part of the curriculum. Only with pure car-control exercises performed on a wet, and then dry, skid pad will you begin to understand (and then become skilled at) skid control talents.
Producing a car control clinic vs. producing a racing school or high performance driver education event costs about the same; the driving public must understand the benefits - safety skills improvement - and realize that investing the time and money for this intense experience is worth it.
So what do you think? Interested in sliding around on a big wet skid pad?
You'll have the time of your life and learn skills that can vastly improve your chances for survival on the road; and if you're a racer, reduce your operating budget by no longer crashing every event.
- Rob Schermerhorn