Driving Mistakes

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As race drivers and trainers, why do we focus on mistakes? First, because mistakes are the best manner of learning. People hate being wrong, so once they do something and are than suddenly made aware of their mistake, they would remember and assimilate the right course of action. Also, because driving mistakes are so natural that they are in times made subconcious and the driver does not know he is doing something wrong with third party observation. If you think the pros don't make the same mistakes, you just made your number one mistake, if the pros would not do mistakes, they would all cross the finish line at the same time. They make the same mistakes as you, just less. To quote Ross Bentley: "The difference between a pro and a beginner is the amount of mistakes they made".

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Driving mistakes

We make one mistake on the average of one minute! These mistakes are mainly psychological in origin and involve our conception of driving, as a trivial, nautral and perhaps "automatic" action. It is not! Driving is a value, treat it as such and treat people who neglect it as those who beatry values. Driving is a prize, not a right. Driving is not just fast, safe or comfty, it can be sharpened to a level of an art.

  • "Auto-pilot" driving: Based on the above assesment, drivers tend to make a habit out of driving. I.E. they form their own -- normally wrong -- habits, and stick to them and are reluctant to change them. They get in the car, put in "auto-pilot" while letting their concentration and mind drift to other places, no thought invested into driving. These people survive via luck, skill of drivers around them, modern safety installments in cars and roads.
  • Lack of concentration and wandering thoughts: Lack of concentration is the number one factor in the category of driving mistakes, and thus the number one factor is crashes and the most dominant skill-limiting variant in driving.
  • Dealing with distractions: Don't focus on the distactions, focus on the purpose: Getting from A to B.
  • Bad visual acuity: On a more practical note, people look wrong. The road is in fact an interface involving a lot of information. Some of that information requires action in the form of changing our speed and/or position. Such information is regarded as a "hazard". Because this information is enormous and must be analysed quickely (because we are moving), the driver cannot take it all in at once. He must built a pattern.
The most popular way is to ignore large parts of information by focusing on what appears to the inexperienced as the most important. I.E. focusing the eyes on a narrow strip of road just slightly ahead of the car. The problem here is that alot of information is missed and that, because we are looking at a small area and just ahead of us, we don't give ourselves the time to take it in. We leave ourselves only time to react, but not to plan. Think about it, if we take it to the extreme and say we only see five feet ahead, how much time passes between the moment when we see and percieve a hazard and the moment when we hit it?
A good pattern involves opening the eyes and looking up and ahead to the furthest distance in which details can be spotted (on a clear day that can even be two kilometers), scan the road with our eyes from side to side and -- when required from the far end to a somewhat closer point. All while letting our peripheral vision monitor our immediate surroundings.
  • Lack of planning: Planning ahead is very important and is achieved, besides by adopting the right visual search pattern, by visualizing in our mind, mentally asking ourselves questions regarding the information we take in (what is the road surface? Width of the road? Distance in which we see clearly? what hazards are visible?) untill those proccesses become natural and subconcious. Take a detailed picture of a road section, or look at a road section (not while driving), take a short peak from side to side and than close your eyes and bring it up in your imagination. Open the eyes and see how much detail of the original image you caught.
  • Lack of safety gaps: It's important to understand that the risk in driving is much larger than thought. However, it is also wider than some of us might think. That's why we tend to think driving is not so complex, because we, and others around us, get away with all sorts of stuff: Speeding, letting go of the wheel, driving tired or even with alcohol in our blood. As said, the reason these mistakes don't nessecarily cost us in the price of a collision, is luck, skill of other drivers, and safety of roads and cars in which we drive. No one hits the road with the intention of being in a crash, yet many do end up like this, either by their own, often unconcious, fault, or by the fault of another -- which can still be mended with the right skill and knowledge.
This knowledge is based on adopting safety margins. The idea is not to avoid the accident, but to avoid the risk of one. This probably makes sense to those of us who are afraid to play russain rollete...This gap exists in various levels of driving:
    1. The driver and his car: Not wearing seatbelts, not seating in a vigilant fashion (particularly relevant for the driver), not fitting children and pets with safety seats and harnesses, travelling with unattended loggage that can be hazards in a crash. This also refers to bad maintenance of suspension and tires.
    2. The driver and the road: This is relevant from aspects of speed relative to the road conditions. One must match his speed to the conditions and not to his perception of safety. Sometimes (I.E. near schools, in busy streets) the right speed is signifacantly lower than that of the speed limit. In other, open innerstate roads, it is in times higher. Vision, density and road conditions affect speed. Another aspect is the maintenance of grip: Modern cars have extremlly high grip levels, much higher than the average driver believes, but they can be reached and when they are reached, the lost of control occurs at a higher speed. Because of these grip levels, drivers leran they can get away with a lot of stuff (coarse handling, driving fast in bends, jerky driving, etcetra), but whenever they misjudge the conditions or are tackled by a surprise (both not intentional) they enter a dangerous field, however saved in times by luck and safety properties of modern cars and roads. It's best to drive in a smooth and percise manner that utilizes the minimal amount of adhesion from the car's overall "budget". Cars basically have a 100% grip, which is divided between acceleration, deceleration and turning. For optimal handling, we need to minimize the overlap between the three. I.E. brake on the straight, enter a corner with minimal brake pressure, than use the gas to keep the car at a constant speed in the corner (so you're just cornering, not accelerationg or decelerating) and than starting to accelerate slightly when you start to open the steering, and keep stronger acceleration only to when you are straight.
    3. The driver and the other road users: Not being courtious, not yielding for others, making agressive lane changes, honking the horn, etcetra. This also refers to counting on others. Like we said, many drivers are saved by those around them, but some are hurt because of those around them. Even when the other driver makes a mistake, an aware and skilled driver can get out it or at least minimze the damage (I know it sounds bad, but the difference between an accident at 60mph and 8mph is hugh!). One should invest is search patterns, constant mirror checks, and maintain a gap of at least two seconds from the driver in front, and try to maintain a gap laterally and even behind.
  • Effect of emotions and experiences -- on the road or off of it -- on our driving style: This is not allowed. Don't be violent or rude to a driver that appears rude to you. Be as quick to forgive others for their mistakes like you forgive yourself for your own mistakes! Don't bring feelings into driving. Make an experience out of it. Instead of talking on the phone, use driving to get some silent, quality time for yourself.

Racing mistakes

Overdriving

Overdriving in the number one mistake in racing! Because our natural road driving in "auto-pilot", we hit the track with our own sense of safety but, on the other hand, with lack of awareness to this new drivig enviornment, without knowing how much resembelence it carries to the public road! A track has lights, signs (flags), lanes (driving lines), shoulders, garages (the pits), traffic, tarmac, etcetra. A track takes the skills of driving a car to the exteme. What works on a track should -- with certain adjustments -- fit road driving too.

Getting back to overdriving, it is the opposite of "auto-pilot" driving. However, it is driving affected by lack of knowledge and by eagerness and lack of discipline and patience. You want the car to go fast now so you bang on the throttle, you want it to turn now so you jerk the wheel very early and very sharply and excessively. This gives the driver the feeling of driving fast because: a) he is constantly at work and his mind interperates this as fast. b) his body is moving constantly which further nourishes that illusion. c) The jerky driving style slides the car -- which many people think to be fast. The car jerks sharply (sharply=quickely), G-forces appear and dissappear rapidly, and the car requires further corrective inputs over the original inputs, which further contributes to (a).

So, overdriving feels fast, but is not fast. An aware driver has the discipline to wait, to search for the right moment, to not "fight" with the car. Instead of turning harder and pressing stronger to get the car to do what he means, he knowns when to stop turning, when to ease off. His inputs are smooth and percise. Instead of feel, eagerness, habits and perhaps fear -- his inputs come from confidence, knowledge and patience, faith even.

Fast corner entry

This is very common. Most people believe a skilled driver (or a race-car driver) can enter a sharp corner very fast. Not true! There are very defined bounderies as to when a car would get into a turn. There are even tighter bounderies as to when such a faster entry would be beneficial. Remember, the turn itself is usually quite short. How much more tenths of seconds can you get by driving slightly faster on a few tens of feet? Alternativelly, how fast will you go if you exit the turn fast and accelerate on full throttle along the following houndreds of metres of straight road?

With anything save an extremlly fast and flat curve, slow corner entry speed + fast corner exit speed = efficiency in the corner. Not safety, efficiency. When we talk about sharp corners, like tight track hairpins or corners on roads, we are talking about a downright "slow" entry speed, much slower than what might "feel" right. With such turns, the anthem is "slow in, fast out" or "fast in, wipe out". If you did not make it out of the corner, your entry speed does not count. Even if you did manage to get through it, you would find yourself "fighting with car" instead of driving it, and this battle with the car would continue into the corner exit and the straight.

It's like a karma: If you do not brake before the turn and even somewhat into it, you will have to brake in it or after it, and lose speed on the straight where you should have full throttle. Alternativelly, drivers often enter fast corners at sub-optimal speed, because they are afraid.

Early apexing

Relating to the last point on fast corner entry, and also for overdriving, drivers tend to stop braking too early, turn-in too early and therefore exit too late, or not at all. You enter a corner from the outside and "cut through it", touching the inside around it's middle, and than let the car run back out. This, in theory, gives you the most straight line through a turn. You actually engineer a straight where it does not exist!

But, if you enter the corner too early, you get a nice, straightish (hence fast) line into the corner but, once you reach the point where you touch the inside of the corner, you find that the corner tightens up just behind it, while you are facing the edge of the road. You have to make steering corrections and decelerate to get the car to turn. Again, driving karma: you try the make the road "too straight" coming in, and you get it "too narrow" coming out. The opposite is also true, but here the trade-off is good, because you increase your corner exit speed.

Now, let's understand "why". The first reason relates to overdriving. You see a corner and you want the car to turn, now! the problem is that to get there fast you need to corner "then", I.E. later. Starting to brake/turn/accelerate earlier does not nessecarily mean you can go faster. Going too early means you are going to get slower. There are additional reasons, one of them is carrying speed into a corner. The driver sees the corner and wants to carry speed into it. Little does he know that there is a payback around the corner: speed on the straight. Furthermore, even when this payback occurs, and the driver is forced to brake or turn tighter, this occurs automatically as he sees the edge of the road coming up. The skidding of the car and the sudden actions of steering and pedaling used to get it back unto the line are interperated by the overdriving driver as fast.

A third reason is fear: The driver is going very fast and sees a corner, his fear makes him tackle the corner from a shallow angle. To wait later would mean getting awfully close to the edge of the road and turn-in at what would appear to be the last possible second. Other reasons involve sight. The driver has narrow tunnel vision and speed and information abundance force him to stare at the road ahead. Suddenly, a corner is due and the driver sees it as a "window of opportunity". A skilled driver knows to look up, see through the corner and past it (while detecting several reference points within it) and mentally draw the line he wants the car to drive through. He than knows to wait for to point where he actually has to look slightly aside from the straightforward position and into the corner and through it, and than see the window of opportunity, not only into the corner, but through it.

Braking

People have lots of problems with braking on the track. Many people wait for the awsome late braking, and than jerk unto the brake out of fear as the corner nears them at speed. However, most drivers tend to be too easy on the brakes, on the track or elsewhere, even in an emergency. Look at brake marks near crash sites and you are likely to see evidence of strong braking just near the crash. Why? First, people are afraid of the brakes. Being the most powerfull means of car control, braking generates a massive weight transfer that can be very unnerving when performed suddenly. At speed, people fear this "jolt" of the car and think that, at speed, it can lead to a lost of control or even a roll-over. Others have heared about things like wheel lockup and fear that the car would skid. The drivers sees whether he can brake more lightly and "get away with it" and only when he sees it's no good, he increases the pressure more and more.

We must understand that at a higher speed, the car's inertia is larger, hence the amount of braking torque to be applied must be greater, and not the other way around. So it's almost the exact opposite, we need to brake hardest and fastest when we initiate braking, and only than begin to ease off gradually parallel to reduction of speed and other variables. This is also true for the road with traffic because -- in the worst case scenario -- we prefer the possibilty of a bump from behind than a sure frontal collision.

There are other reasons for this hesitation: An often less than optimal seating position, a fixation of the eyes unto the hazard. rather than the ground in front of it (where you want to already stop) or besides it (to which you want to veer) and also, because our everyday braking attempts are subtle and gentle. When we brake in an emergency, or attempt threshold braking on the track, we try to stomp on the brakes (and we think we are), but in fact we are placing our foot on the pedal (while applying considerable pressure, but not quite stomping on it) and try to press it further. The problem is that now our heel is resting on the floor and is used as an axle, over which braking is performed, making the braking effort much more progressive than it should be. As we near the hazard, speed decreases and our fear increases as the obstacle draws nigh, so we progressively increase our braking pressure.

With the last mistake, we took into mind that brakes are the strongest means of car control available to the driver. Hence, it is by braking that we can generate a larger change in lap times. How come? We are on the straight on full throttle -- fact. We see a corner that requires a serious reduction in speed -- fact. If we manage to excert every bit of performance out of them brakes, we would be able to brake over the shortest possible distance, and thus keep full throttle to the last possible second. The brakes being the strongest means of car control is another reason that makes fast corner entry detriment and out of question: Because they are so strong, every fraction of a second of braking too late is going to be dramatically too fast, usually too much for making it through the corner.

Getting on the drive too early

While it is important to get on the drive unto the straight following the corner, there is a limit as to how early we can get on it. When we enter the corner, we should still be rolling off of the brakes. In the corner, we should apply throttle at a rate that keeps us on a constant speed (it's not nessecarily a static amount of throttle!), and only around the APEX can we accelerate out, progressively. I like to segregate a corner into three phases: Turning-in, turning, and tracking-out. Turning-in is the stage between braking before the corner and than turning the wheel in while trailing off of the brakes. Turning is once the steering angle and lateral weight transfer has been established and the driver maintains neutral throttle. Tracking-out is when the driver begins to "open" the steering wheel. Remember, the throttle is not an on/off switch!

Remember: You cannot get on the drive before you start turning and you cannot accelerate before you begin tracking-out. Think of a string attached between the throttle and steering. More steering = less throttle (even to the degree of negative acceleration = braking), static steering = balanced throttle. Less steering = more throttle. So, at the moment you stopped turning the wheel in (with the exception of the faster corners negotiated with some throttle all throughout) you get on the throttle just to get the car stable. Once you start taking the steering input off, you begin to actually accelerate. With the excpetion of changing radius corners, acceleration will only begin once you see through the corner as it "opens up".

Not using the whole possible width of the road

"You paid for the whole track, use the whole track!" Well, I listed that one relativelly low because I think that categorily using the whole width of the track is not applicable, due to: traffic, high curbs, slick or sloped portions of the track, choice of corner lines, rain lines, pit lanes, etc. Likewise, there are times when we can use more than just the track and actually cut the corner and let one or two wheels drop off of the pavement slightly. There are simply to much variables to categorily say that you should use the whole width of the track. Instead, use the whole possible width of the track.

Why use the width of the track? Let's recap corner lines. When we enter a corner from an inside, sharp line, we get a short way through the corner, but a very jerky and slow line, late resuming of acceleration and poor visibility through the turn. When we take the highline and drive around the outside of the corner, we get a wide, smoother line, with more vision, but an even later resume of acceleration and a very long time inside the corner. So, what if we combine the two? We reach the corner from the outside, that start "diving" inside, cut the corner's inside line at around about it's center, and than let the car run back out, wide. This makes the corner longest, but more smooth and straightish. How come? Because we use not only the length of the road, but also it's width.

Most drivers will not come into the corner far enough, will not clip the apex close enough to the inside and will not let the car track out as far as possible. This reduces stability and speed. Particularly with tracking out, because tracking out actually makes the straight (and the acceleration phase) longer.

Not using weight transfers

Old school racing drivers and even advanced road drivers, will tell you that all phases must be completly segregated. I.E. you brake before the corner, finish braking in a straight line, enter the corner with the car stabilized on balanced throttle, and than accelerate at exit. The problem with this approach, which is no longer practiced by the majority of institutions, is that some parts of usable adhesion are "lost" and the transients are slowed down. Instead, one should keep the stages overlapped, but to the slightest degree possible. When entering a corner, you keep the brakes slightly on and trail off of them as you turn in. You turn the wheel two degrees and back off some pressure, you turn an extra four degrees and you back off of twice as presure. You are sharing the braking and steering. Likewise, you share steering and acceleration: You open the wheel and accelerate, you continue to open the steering and you accelerate even harder.

Why? because this induces weight transfers. Now, any track driver or car engineer will tell you that weight transfers do not increase overall grip. They just re-distribute it, damaging the balance of the car and perhaps even reducing overall grip levels. That is all very true but weight transfers are beneficial when minimal and momentary. I.E. going into the corner, we would benefit from the slightest forward weight transfer, which is going to push harder against the front tires and stick them to the road. Going out of a corner, we will benefit from weight transfer to the rear and "pull" the car straight and ahead with the gas pedal. Weight transfers are beneficial in transients: from straight-forward to turning-in, from turning-in to turning, from turning to tracking out.

Using weight transfers also relates to the balance of the hands versus the feet. Naturally, one hand has better control and feel than both feet, but as speed increases and the levels of grip are maxed-out, the pedals begin to take a more dominant role relative to the steering wheel. When we turn the wheel, we turn the front wheels, but the tread of the tire still wants to carry onward, so it twists aside and tries to keep pointing straight. This is called a "slip angle" and it is the difference between the direction the wheel is pointed and where the tread is actually pointing and taking us to.

A slip angle can be viewed as a "request" for cornering force. I.E. the wheel does not make us corner, by turning the wheel we tell the car to "ask" the laws of physics whether it could turn and how much. The laws of physics can say: "yes", "no" and can also change the amount of turning. Even once a turning force (lateral acceleration) is initiated, slip angles continue to exist. In fact, we have just applied a new force unto the car (Centripetal force), plus caused a distortion of not only the tread, but also a distortion of the tire as a whole, a distortion of the wheel, a compression of the suspension, roll and twisting of the chassis, and generated yaw (rotation) and a slip angle to the rear. By turning the wheel we do a lot more than just turning the front wheels.

With the pedals, throttle and brakes (and clutch when the grip levels are dramatically low), the driver has direct control over weight distribution and of the slip angles of all four tires. The more adhesive force is used by braking or acceleration the less is used for cornering and larger the slip angles turn. Also, more weight on a tire can (in theory) lead to a smaller slip angle and vice versa. What do I mean in practice?

Remember early apexing? The driver dives into the corner to early (and normaly too fast) and than finds that it gets too tight at the exit and he is facing the edge of the road? Remember what that driver instinctivelly and subconciously tried to do? Yes, turn the wheel more. Now, what than happens? The effect is that the tire -- which is sliding forward because it cannot fullfill the driver's requests, now has even more requests to deal with. Sometimes, the driver will actually get away with it because this causes the the wheel to slide harder and slow down. As it slows down, weight is transfered forward and unto it, giving it the extra downforce that sticks it against the tarmac, making it grip. However, we should consider three things:

  • The deceleration created by the brakes is much larger than that created by steering drag.
  • With this corrective input, what we do in fact is to turn more and more lock on and than -- when we run out of it -- wait for the car to lose enough speed as to re-grip, hoping that the car would run out of speed before it runs out of road.
  • Under panic, the driver can overdo this easily. I.E. He sees the edge of the corner comes awfully close, he jerks the wheel away from it as hard as he can, but the car does not respond so he just turns it more to the very edge of the rack. What now happens? The slip angle has now grown so large, as to a state where it no longer faces the road with the tread, but rather with the profile or "shoulder".
The tire is not able to roll in such an angle, plus the shoulder is made out of less grippy rubber, so we actually scrubb off speed less effectivelly, use more of our 100% adhesion budgest, and increase the angle for which the car must compenstate. That is, when we keep the wheel static (or even take some of the steering off), the car only has to tighten it's line slightly more to "recover". When we turn more and more, the car has more tightening up to do before it can return to normal driving state. In the latter, it might even over-compensate and turn the situation into a spin.

Another situation is when the back end of the car (opposite to the former example) is the one sliding. The tail of the car swings around, which rotates the front of the car all too much into the corner. In this case, there are two types of people: The type that rolls onto the brake in panic (but does not brake nearly as hard as they should), and the type that tries the steer away from the obstacle and back unto the right track. Picture this: You reach an exit ramp coming off of the highway. You come off quickely and as you begin to corner you find you are too fast.

You turn more steering but the car does not tighten up the line as quickely as you expected and, as the wall to your left draws near, you jerk off of the gas or unto the brake and whops, the car over-reacts (because you over-reacted) and rotates too much into the corner, and now the back of the car broke away and tries to spin you, you are now facing the fence to your right. You steer left and away from it, back towards the right direction (you in fact steering "against" the slide or "into" it).

But, again the car fails to react as quickely as you wanted. I.E. It does not spin, but it does not straighten-up either. You turn the wheel more and more and you run out of steering. You look at the fence and hope to stop before you hit it but alas! you run out of road first, your tail bashes the fence, and than the front remembers to swing around and also hits it. Outch! Another scenario is that, when you turn the wheel more, the car suddenly over-reacts in a certain moment and the back swings to the other way. Now, you have already turned the wheel some 270 degrees one way. Now, how much steering are you going to have to apply to catch the second slide? You inevitably fail and hit the wall at speed.

Instead of either of those scenarios, you would need to understand what happened to have caused the slide and than do the opposite. What happened is that you turned the wheel sharply into the corner and than jerked unto the brakes. This created a forward weight transfer that got the front to obey to you, but the rear has been rendered very light (in times even practically airborne) and without the ground to "hold it" it swings aside. In fact, you have increased the rear slip angle too much. Yes, like with when the front wheels skid, you can try to compensate for this by reducing the front slip angle and trying to the wheel the other way, but again the effectiveness of this correction is lesser than when using the weight transfer. The problem here is that the weight transfer nessecary it back unto the tail of the car, which means getting on the gas. This is counterintuitive and very complicated to perform accuratly.

Now, the wheel should never be neglected. The pedals are more important, but often not by much. In both situations described above, there was a certain steering correction required. The way to get it right is to look into the corner towards where you do want to go, and not towards the obstacle you are skidding towards, to which you do not want to go. Looking in the right direction and preferably to a distance, would help make you inputs more timely and avoid unnessecary additions of steering input for the car to overcome. Think, if you are looking five feet ahead and the car turns one degree tighter or less tight than what you want, than you will not notice a significant change. If you look one houndred feet ahead, any slight change in the car's direction would translate into a hugh change in where your eyes are pointed, making you more away of any movment of the vehicle. This relates both for prevention of such situation, for sensing them when they do occur and for getting out of them without overcooking things.


Driving myths and misconceptions