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Whether driving to the mall, driving the boss to work or driving in a high risk environment most driving is done in the Comfort Zone. The Comfort Zone is a combination of speed – steering and/or braking where the vehicle reacts as the driver expects it to. The Red Zone is a combination of speed – steering and/or braking that creates big changes in the way the vehicle responds, changes that are not expected, and create anxiety. Unless it is a race, the Red Zone is not a place a driver would go to on purpose, it is a place visited only when bad things are happening.

 It  may be difficult to think of a 10,000 lb armored Suburban as “sensitive”, but a car’s controls are very sensitive to speed, the faster you go, the more sensitive the vehicles braking and steering become. This area of sensitivity is the Red Zone.

 Research indicates that going from the Comfort Zone to the beginning stages of the Red Zone, happens with an increase of a fraction of an inch on the steering wheel, and/or an increases of speed as little as 2 MPH. To complicate the issue research has also shown the driver gets into their own personal Red Zone way before the vehicle does. As the driver enters Red Zone the vehicle will send feedback that makes the driver feel uncomfortable (the researcher’s way of saying scared). At this stage of the Red Zone the vehicle is still controllable, but the level of skill needed to keep the vehicle under control has gone up dramatically, and the window of opportunity to maintain control is extremely small.

 Look at it as the vehicle has a limit and the driver has a limit. The drivers limit is much lower than the vehicles limit. Basically the driver is uncomfortable with a combination of speed – steering and/or braking that are below the amount of speed – steering and/or braking the vehicle can take. 

 It is the transition from Comfort to Red that creates a training challenge. In an emergency a driver will be required to quickly transition from their Comfort Zone, into the Red Zone, there can be no hesitation. Common sense dictates that a driver has to be trained to recognize and manage this transition. In our opinion this transition is the essence of driver training. One of the goals of a driver training program is to raise the amount of steering, braking and speed a driver is comfortable with.

First this is a rare occurrence, but it can and has been fatal. One of the fatal incidents happened in my home town – Medford MA.

 If this event happens there are two things you want to do quick – real quick. Slow the car down and disconnect the engine from the drive wheels.

 Here are some things you can do; Press on the brake pedal – brakes can and will overpower the horsepower created by the engine. In a test done by Car and Driver magazine here is what they found “With a Camry’s travelling 70 mph, the brakes easily overcame all 268 horsepower – and stopped the car in 190 feet—that’s a foot shorter than the performance of a Ford Taurus without any gas-pedal problems and just 16 feet longer than with the Camry’s throttle closed.”

 Also from the same  Car and Driver  article – “If this is a concern, in the future look for vehicles with electronic throttle control since the advent of electronic throttle control, many automakers have added software to program the throttle to close—and therefore cut power to the engine”.

 Shift into neutral this will disconnect the engine from the drive wheels – don’t worry about the engine revs going crazy – most cars have rev limiters. But if your gas pedal is stuck and you are travelling 60 MPH or 90 Feet in a second, the least of your concerns is the engine revs.

 Keep in mind where you are. If you are on a major highway you don’t want to stop in the passing lane, the people behind you will get cranky. Once the car is in neutral you can control the speed of the car with the brake pedal. Get the car safely to the side of the road and if you can, off the road. DO NOT shut of the engine while the car is moving. Shutting off the engine will make the car hard to steer, just adding more excitement to your life.

 Once the car is stopped shut off the engine, take a deep breath.

All vehicles are supported by a cushion of air contained in four flexible rubber tires.  If you could place a car on a glass floor and look at it from below, you would see four patches of rubber, most folks are surprised at the size of these four patches, depending on the vehicle – each patch a little smaller than a hand.  These are the only points of contact between the vehicle and the road.  Each of these four small patches of rubber is known as the “contact patch”. It is these four patches that create the traction which makes the vehicle – go – stop and turn. It is these four patches that send the feedback back to the driver, and it is these four patches the driver has to manage. Consider them to be the source of information needed to control the vehicle.

 How Much Rubber Do You Have?

If you conduct training and want to know the size of the contact patch your vehicle creates, jack up your vehicle, put ink on the bottom of the tire, and let the car down on a piece of paper (we use finger print ink). Have someone keep their foot on the brake as you let the vehicle down, it keeps the tire from rolling, and lower the tire on the paper – the tire will leave a mark on the paper that represents the tire contact patch. The paper should be outline paper dived in one inch blocks, it makes measuring the contact patch easier.

 Once done you have a “picture” of the tire contact patch, and can easily measure the size of the patch in square inches (width of the patch times the height of the patch). If you take that number multiply it by four that is how much rubber is on the road.

 In our vehicles, police package Crown Vics with P225/60R16 tires with 32 PSI, we have 36.75 square inches per tire and all four tires will give us of contact area of 147 square inches of rubber touching the road.

DESIGNING DRIVING EXERCISES

The purpose of  placing a student in a given exercise or scenario is to evoke a response from the driver/vehicle which introduces or reinforces specific skills or skill sets , and to afford an opportunity to coach the student on applying those skills and, of course, measure their baseline performance and quantify their improvement. None of this can be accomplished without understanding of vehicle dynamics. This understanding leads to questions that a professional driving instructor asks and can provide answers to:

 How far apart are the cones in the slalom?

What is the width of the barrier in the lane change?

What is the maximum capability of the vehicle, measured in G’s, in each exercise?

What is the maximum rate of de-acceleration of the vehicle?

At what speed does the student approach the vehicles maximum capability in each  exercise (or scenario) that you place them in?

Why are the answers to these questions so important? Because if the instructor does not know the maximum capability of the vehicle and what conditions and/or limitations an exercise will impose on that vehicle, it is impossible to measure the capability of the driver. And if the instructor cannot determine what the driver was capable of at the beginning of their training and then compare that to what the student is capable of at the conclusion of their training, there is no way to determine if the training was effective; in fact, there is no way to establish and meet objective goals for the training.  Perhaps more importantly, without measuring the student’s capability there is simply no way for them to fully recognize what they can, and cannot, do behind the wheel.

 Ultimately, you cannot separate vehicle dynamics from driver training; hence instructors MUST have a thorough understanding of vehicle dynamics and the ability to apply that knowledge to driver training.  Because once they have that understanding, they then have the ability to provide training that incorporates the three critical factors of survivability behind-the-wheel emergencies – the driver, the vehicle and the environment – into exercises that not only provide a mechanism for measuring the driver’s improvement, but also closely replicate the types of emergencies he or she is likely to face.

 For an example of just how advantageous this understanding  can be to the instructor, we  just need to look  back at a an Instructor-level Vehicle Dynamics and Exercise Design program TSVDI conducted for a Federal Agency. When we passed out the calculators (standard issue for the vehicle dynamics savvy instructor), one of the students was looking at the calculator like a monkey might look at a watch – confused. It wasn’t long before he came up to Tony and expressed his displeasure that he would have to learn math to pass the course. He, like many others we have trained, pointed out that during his high school days; (with some it even extends into their college days) math was the bane of his existence. In a roundabout way he made the point that he was concerned that he would not pass the course because of the math. Tony’s answer was the same for him as it has been for scores of others with the same concern – hang in for a few days, and give it your best shot, while we give our best shot to teaching you the math.

 Three days later, as we were on the track designing a training exercise to recreate a specific incident that involved their unique vehicles and the difference a new found knowledge of math and vehicle dynamics made was quite obvious. Tony had put together some guidelines for the students regarding the exercise design elements, and this same guy that had , just a couple of days before, been concerned about passing the course walks up to him  and says “I don’t agree with the way you suggested we design this exercise”. He then proceeded to walk Tony through nearly a full page of calculations he had worked out to express how he thought the exercise should be designed and thoroughly explained why he thought that. In just a few days this instructor had gone from being intimidated by the math required to design driving exercises to combining his knowledge of the laws of physics (and, god forbid, math)  with his operational knowledge of the agencies mission objectives, the unique vehicles they operated and the types of incidents they had faced in the past to develop an exemplary driving exercise; one in which the drivers capability to resolve the problem while maintaining control of the vehicle was able to be objectively measured and, more importantly, drivers would be able to recognize that they were fully capable of resolving successfully.

 At the end of the day, that is the real value provided by an instructor who understands vehicle dynamics and how they apply to drivers training.