Turns. Question: Why should a car driver slow down before turning a road? Why does the driver reduce speed when turning corners? Physics
Similar questions
- .Test on the topic “Man in the social dimension.” A1.Which of the following refers to the biological characteristics of a person? 1) Communication 2) Speech 3) desire for self-affirmation 4) ability to walk upright A2. What are the actions of animals based on? 1) on consciousness 2) on instinct 3) on thinking 4) on reason A3. The set of qualities acquired by a person in the process of living in society: 1) character 2) individual 3) personality 4) instinct A4. Which of the following refers to the social characteristics of a person? 1) brain volume 2) lack of hair 3) care for offspring 4) need for communication A5. A person’s knowledge of his inner world is: 1) activity 2) self-knowledge 3) abilities 4) needs A6. What determines a person’s mood at one time or another? 1) Emotions 2) Feelings 3) Judgments 4) conclusions A7. Are the definitions correct: A. A judgment is a statement containing a certain thought. B. Inference is a conclusion from several logically related judgments? 1) a is correct 2) b is correct 3) both answers are correct 4) there is no correct answer A8. Human social needs are: A. The need for communication; B. The need to understand the world around us. 1) a is correct 2) b is correct 3) both answers are correct 4) there is no correct answer A9. The ancient rite of passage of young people into adults is called: 1) self-knowledge 2) affect 3) self-esteem 4) initiation A10. The common features of humans and animals are: A. Biological needs. B. Use of natural objects. 1) a is correct 2) b is correct 3) both answers are correct 4) there is no correct answer A11. Which of the following is not a biological need? 1) Nutrition 2) Rest 3) Communication 4) movement A12. Both humans and animals: 1) have coherent speech 2) can think 3) act consciously 4) use various objects A13. Which of the following is inherited? 1) eye and hair color 2) position held 3) choice of profession 4) love of reading books A14. Originality, uniqueness of a person: 1) personality 2) heredity 3) emotionality 4) individuality A.15. Are the following judgments about activity true: A. Activity is an activity inherent in both humans and animals B. Many scientists consider communication to be an important type of activity 1) only a is true 2) only b is true 3) both answers are correct 4) there is no correct answer A16. Are the judgments about a person’s abilities correct: A. Abilities can manifest themselves very early; B. Are there people who have no abilities? 1) only a is correct 2) only b is correct 3) both answers are correct 4) there is no correct answer A17. Are the judgments about needs correct: A. Human needs are divided into biological, social and spiritual; B. It is impossible to fully satisfy all human needs 1) only a is correct 2) only b is correct 3) both answers are correct 4) there is no correct answer A18. Is it true that A. The same events give rise to the same feelings in people B. Emotionality is not inherited 1) only a is true 2) only b is true 3) both answers are correct 4) there is no correct answer A19. Are the judgments about emotions correct: A. Emotion determines a person’s mood B. Emotions can be both positive and negative 1) only a is true 2) only b is true 3) both answers are correct 4) there is no correct answer A20. Are the following judgments about personality true? A. Personality arises as a result of the biological development of a person. B. Society has a huge influence on the development of personality. 1) only a is correct 2) only b is correct 3) both answers are correct 4) there is no correct answer A21. Are the following judgments about personality true? A. Personality is formed in interaction with other people. B. Personality is formed throughout a person’s life. 1) only a is correct 2) only b is correct 3) both answers are correct 4) there is no correct answer A22. Are the following statements true? A. A person can determine what he is like by comparing himself with other people. B. Self-knowledge allows 10:36:17 to identify in a person his most important features, the essence of his “I”. 1) only a is correct 2) only b is correct 3) both answers are correct 4) there is no correct answer A23. Indicate the differences between human activity and animal behavior. 1) Interaction with the outside world 2) Adaptation to the environment. 3) Having a thoughtful goal. 4) External activity. A24. Choose the correct answer. What unites the words “game”, “learning”, “work”. 1) These are the needs of the human body 2) These are the types of activities 3) These are the qualities of a person 4) These are the ways of earning money A25. Choose the correct answer. Which of the following is NOT a distinctive feature of human activity 1) Defining a goal 2) Conscious actions 3) Analysis of the result 4) Instincts A26. There is a proverb: “Shoot sparrows from a cannon.” This proverb is used when a person 1) Does not plan his activities 2) Does not analyze the result of the activity 3) Incorrectly selects the means to achieve the goal 4) Incorrectly sets goals A27. Choose the correct answer Social needs include A28. Choose the correct answer. The need for rest refers to
When turning, a car experiences additional external forces, in particular centrifugal force, which are absent when driving on straight sections of the road. Centrifugal force tends to move the car to the outside of the road's center of bend. Its value depends on the weight of the car, the radius of curvature and the square of the speed. That is why, at high vehicle speeds, it is dangerous to make sharp turns of the steering wheel, performed in minimal time intervals: in this case, the radius sharply decreases, and the centrifugal force increases accordingly.
There is a fair opinion that there are no two identical turns on the road. Each turn has a different radius, a different slope, a different surface, a different visibility or a different environment. Therefore, the driver must evaluate each turn and select a speed limit that ensures the safety of that particular turn, taking into account its inherent features and surprises. When turning, you should never look at the road directly in front of the car, You should look at the end of the turn or at a further visible part of the road . Then the driver will not only be able to correctly determine the turning radius, but will also see whether anyone is approaching from the opposite direction, and whether the road on his side is clear.
When driving around a turn, you must not allow yourself to slip, which could lead to loss of control of the vehicle. If a driver hears squeaking tires while turning a corner on a dry surface, it means he has reached excessive speed. You cannot cut corners; you must always drive on the right side of the road. When turning, you should not brake, change gears, or press the throttle control pedal too sharply. All this can lead to a dangerous situation.
The correct turn should be carried out as follows: before approaching its beginning, it is necessary to reduce the speed to an appropriate limit determined on the basis of experience; the beginning of the curve should be passed without increasing the speed of rotation of the engine crankshaft, but also without even braking the engine; at the same time, without jerking, gradually turn the steering wheel, accelerating its rotation as the curvature of the turn increases; from about halfway through the turn, gradually increasing the engine speed so as to exit the turn at a speed equal to the speed before starting the turn. You also need to turn the steering wheel back to the main position without jerking and gradually.
It must be remembered that, due to the inertia of the car’s movement, the turn should begin somewhat earlier than the start of the actual curve of the road, and it is also necessary to exit the turn accordingly earlier. The magnitude of this advance is determined on the basis of long-term experience. Correct execution of turns is characterized by the absence of skidding and smoothness. The steering wheel must be held firmly enough with all fingers and the palms of both hands. possible, you should not shift your hands, but rotate the wheel without taking your hands away from it. You cannot cross your arms. If, on a turn with a very large curvature, for example on mountain serpentines, the driver needs to change the position of one hand, then it is necessary that the other hand always tightly grasps the rim of the steering wheel. It is prohibited in all cases to remove both hands from the steering wheel at the same time. One of the difficult tasks for the driver is to quickly and accurately determine the amount of curvature of the turn and hence choose a safe speed.
171. Why do passengers lean backward when the speed of the bus suddenly increases, and forward when it suddenly stops?
With a sharp increase in the speed of the bus, the passenger’s legs begin to move forward, and the upper part of the body continues to move by inertia at the same, lower speed. When braking, the passenger's legs begin to “go” back, and the upper body moves forward.
172. What change occurred in the movement of the water tram if its passengers suddenly deviated to the right?
The water bus turned sharply to the left.
173. The ball, which was lying calmly on the table of the carriage with the uniform movement of the train, rolled forward in the direction of movement of the train. What change occurred in the movement of the train?
The train began to slow down.
174. Place a postcard on a glass, and place a coin on the postcard. Click the postcard (Fig. 35). Why does the card fly off and the coin fall into the glass?
Due to the brevity of the interaction, the friction force between the card and the coin does not have time to impart sufficient speed to the latter. The postcard flies off and the coin, having lost its fulcrum, falls into the glass.
175. While chopping wood, an ax got stuck in a log. Figure 36 shows in what ways the log can be split in this case. Explain them.
In the first case, the log stops abruptly, and the ax, moving by inertia, splits it. In the second case, a log moving by inertia splits on a stationary axe.
176. Figure 37 shows how to place a shovel on a stick (handle). Explain them.
In the first case, the inertia of the shovel is used, and in the second - its handle.
177. Why can’t you cross the street in front of nearby traffic?
Due to the phenomenon of inertia, vehicles cannot stop instantly and, after braking begins, continue to move forward for some time.
178. Why is it prohibited to tow a car with faulty brakes using a flexible cable?
When the towing vehicle brakes, the towed one moves forward by inertia and collides with the first one.
179. Why does the chuck continue to rotate after turning off the drilling machine motor?
Due to the phenomenon of inertia.
180. Why does a cyclist, approaching a rise in the road, increase his speed?
To rise as high as possible due to the inertia of the bicycle.
181. Why do the driver, driver, or cyclist reduce the speed of the car when turning?
To prevent skidding.
182. Why is a passenger required to fasten his seat belt before takeoff and landing of an airplane?
In order to avoid flying out of the chair as a result of inertia during a sharp change in speed.
183. Why should the rear red light on a car turn on when the driver of the car presses the brake pedal?
To warn vehicles behind him to slow down.
184. Why do raindrops fly off clothes when shaken sharply?
When shaken sharply, the water drops continue to move by inertia.
185. Why shouldn’t a tractor, while towing a car, suddenly change its speed?
When braking sharply, the car driver may not react, and the car, moving by inertia, will collide with the tractor.
186. Coming out of the water, the dog shakes itself. What phenomenon helps her in this case to free her wool from water? Explain your answer.
see No. 184.
187. Cargo is dropped from a flying plane. Will it fall to the ground below where it is thrown? If not, where will it shift relative to this place and why?
The load will shift in the direction of the aircraft's velocity vector. This is explained by the phenomenon of inertia.
188. Why is it forbidden to suddenly lift a load with a crane?
As a result of inertia, the tension in the cable holding the load increases sharply, and it can break.
189. What is the cause of destruction during an earthquake?
During an earthquake, as a result of inertia, parts of buildings begin to move at different speeds and a gap occurs between them.
190. Why does a ruler suspended on paper rings break when struck sharply, but the rings remain intact?
With a sharp impact, the ruler will break faster than the disturbance reaches the rings.
191. How is the free surface of oil located in tanks when the electric locomotive that sets them in motion picks up speed; slows down?
The free surface of the oil will be inclined relative to the ground. When the speed increases, oil will be thrown toward the end of the tank, and when braking, it will be thrown toward the beginning. This is explained by the inertia of oil particles.
192. Will a ball dropped from a hand in the carriage of a uniformly and rectilinearly moving train fall under the place of throwing?
Yes, it will fall, since both the ball and the floor of the car are moving relative to the ground at the same speed.
193. Give examples when inertia is beneficial and when it is harmful.
Inertia benefits a person when he shakes off clothes, chops wood, or hooks a fish with a fishing rod. Inertia causes harm to bus passengers and the crane operator.
194. Why is it easier to jump over a ditch with a running start?
Because the speed is greater.
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Turns
Cornering technique
The recommendations contained in this chapter can be summarized in two sections. The first involves actions that protect the car from getting into critical situations, the second involves emergency driving techniques. Among both, there are options that are quite accessible even to an untrained driver, although some of the most effective techniques require a higher level of professional skill and systematic training work.
Anticipatory actions
- When approaching a turn, try to determine the steepness of the arc (turn category) and its complexity (length of the arc, shape of the curvature, nature of the surface, presence of a shoulder, slope of the road surface, types of irregularities). Concentrate so as not to make a mistake and not underestimate the category of the turn.
- Determine the critical speed of the approaching turn and compare it with the actual speed of your car to choose the optimal braking method: either low-intensity or emergency. Consider your own capabilities (skill).
- By slowing down before an unknown turn, you will lose less than 1 second because you will be able to start accelerating at the exit earlier. But you will acquire a safety margin that will eliminate the possibility of getting into a critical situation.
- Before entering a turn, move the vehicle to the outside of the road to increase the radius of movement and reduce the effect of centrifugal force. If the road is two-lane with oncoming traffic, then the shift is performed on the occupied lane.
- It is almost impossible to continue intensive braking and try to switch to an arc at the same time. Finish one operation first and then move on to another. You can apply the brakes during the turn arc, but first you will enter.
- Downshift during the approach phase while the vehicle is stable on the road. When turning, this action can compromise stability.
- If you are in doubt about which gear to negotiate a corner in, protect yourself from a critical situation by engaging a lower gear. This will allow you to maintain engine power at a relatively high engine speed.
Counter-emergency actions
- Before starting the maneuver, load the front wheels with the weight of the car, using one of the braking options: the engine (suddenly stop the fuel supply), engaging a downshift, or the service brake (stepped or intermittent braking). Be sure to time the maneuver to coincide with the moment of release of the brakes at the last braking force.
- After starting to enter the turn, immediately apply traction to the drive wheels (gently press the fuel control pedal). This will increase the car's handling and ability to counteract centrifugal force.
- Do not try to immediately switch to the inner radius. By reducing the radius, you increase the centrifugal force and create difficulties for yourself in the second part of the turn. Construct a path with a maximum radius (smoothing path), starting and ending the turn on the outside and turning inside at the steepest part.
- If the car approaches a turn in a high gear, you can engage a downshift corresponding to a certain category of turn already on the arc. But the activation must be “soft” so that there is no acceleration or deceleration that will lead to the car skidding.
- Do not use impulse braking techniques (stepped and intermittent) when turning at a critical speed. They can cause the vehicle to lose stability due to short-term or long-term wheel locking. Use smooth braking with a small constant force, but remember that its capabilities are limited. You can reduce excess speed by no more than 20 km/h.
- Beware of uneven surfaces under the vehicle's outer wheels. These wheels provide stability. A wheel bouncing or falling into a hole can cause a side slip. It is better to overcome unevenness in a turn in a straight line, using the “double stroke” trajectory for this. This trajectory includes two mini-turns and a transition straight line or curve between them.
- On a front-wheel drive vehicle, abruptly closing the throttle briefly on an arc causes the rear axle to slip. This moment can be used to reorient the car towards the inside of the turn. However, this must be followed by thrust in order to create a stabilizing moment and increase the stability of the vehicle.
- Make a sharp turn at high speed not along a classic arc, but along a polyhedron (broken path). This trajectory will allow you to avoid a serious mistake. Achieve this with short steering pulses of less than 1 cm amplitude and variable throttling.
- Before increasing the crankshaft speed to maximum, place the car at the exit of the turn on four points of support, ensuring that all wheels are equally loaded. To do this, you need to align it and move it to the outside of the turn.
- If you were unable to reduce the critical speed before entering the turn, then stop braking and sharply drive the car into an arc, directing it towards the inner shoulder. The centrifugal force will immediately throw it into a side slip, which will allow it to extinguish the excess speed.
- When the car is sliding with its front wheels, do not make the mistake of turning the steering wheel at a steeper angle, much less pressing the brake pedal. Reduce (!) the angle of rotation of the wheels, load the front wheels with braking and re-enter.
- If you find yourself in a skidding or spinning situation and lose power while struggling to stabilize the vehicle, try quickly downshifting. This will restore power to the car.
- Beware of the vehicle's sideways slip turning into a spin. Avoid braking and sudden throttling in such a situation. Take advantage of the quick release and engagement of the clutch. This technique will allow you to equalize the speed of rotation of all wheels.
- While in the turning arc, maintain constant, steady engine thrust. You can add additional load to the sliding front wheel and stop the sliding of the rear wheels by briefly “covering the gas”. But throttling cannot be stopped completely. This will cause a loss of stability and controllability of the car.
- React to a skid by sharply jerking steering in the direction of the skid and quickly returning (aligning) the steering wheel to its original position.
- When a front-wheel drive car skids, it is not necessary to react by turning the steering wheel in the direction of the skid. The sliding of the front axle caused by sudden throttling can be used for leveling.
- Controlling a corner on a slippery road can have the dual benefit of slowing your vehicle and helping counteract centrifugal force if you increase engine speed. However, to use it to your advantage, one must have the skill to stabilize the vehicle in such an unstable state.
- A skid can develop into a spin; If you are late to react, perform stabilizing actions at low speed or sharply increase the engine speed.
- By reacting late to a skid while the throttle is closed, you risk causing a skid in the opposite direction. Do not wait for it to occur and get ahead of it by jerking steering at the moment when the car changes the direction of the skid and seems to “hang” in an unstable position.
- A skid can turn into an uncontrolled sideways slide if you lock all the wheels by braking. Both when skidding and when rotating, do not use the brake pedal. The position of the car is regulated only by throttling and high-speed steering.
- If you are turned 180° in a skid, immediately disengage the clutch, and if you don’t have time, turn the steering wheel all the way in the direction of rotation. This way you will “turn” the car to an angle of 360° and will be able to move in a forward direction again.
- Remember that it is very dangerous after an unexpected rotation or a critical skid to find yourself across the road, both in the flow of cars and on a narrow roadway. By blocking the road, you force other drivers into a collision. Use rotational inertia or steering and throttling techniques to "turn" the vehicle to 180° or 360°. Even if your car is in the oncoming lane, it is much easier to go around it if it does not stand across the traffic and block the road.
- When, after a mistake you made, the car is carried off the road and the two outer wheels end up in a deep ditch, do not try to immediately return it to the road by sharply turning the steering wheel. In an unstable deep tilt position, this action will cause the machine to tip over. First, return the car to stability, and then try to return it to the road.
Cornering tactics
There is a whole area of driving knowledge, skills and abilities associated with cornering at high speed. It is no coincidence that all high-speed types of motor sports: circuit racing, rallying, cross-country racing, track racing, etc. are connected to one degree or another with the skill of cornering. Highly qualified racers have simply delicate and super-stable control techniques and tactics. Watching Formula 1 races, you are often amazed that the difference in the results of completing a lap more than 3 km long with dozens of difficult turns is hundredths of a second for different athletes. But even great racers make mistakes. Most often this happens because they exceed the so-called “speed barrier” - the level of psychological, physiological and technical safety.
When faced with an extreme situation on the track, a driver can only rely on the reflex reactions of his body, which are brought to a high degree of automaticity. It is almost impossible to “pump” an acute situation through consciousness - there is no necessary time to think about it. Either a reaction of anticipation (anticipation), or an accident of varying severity.
If you compare a super racer on a competition track at the limit with an ordinary motorist who is trying to go too fast around a corner on a country road, then the second is obviously in a more dangerous situation. And it's not a matter of skill level. There is another problem, no less important - the ability to predict one's own safety.
The racer, unlike an ordinary driver, realistically assesses the speed limit and prepares for any surprises on the road. During the race, his heart constantly works at its maximum (170-180 beats per minute). Having merged with the car into one whole, it receives express information from the operating systems of the car, maintaining the trajectory of movement, road stability, and controllability of the car through continuous correction. Understanding and anticipating the car's reactions to its own control actions, the driver intuitively anticipates problematic situations, preventing the car from getting out of control.
An unprepared driver, finding himself in an acute situation on a turning arc, begins to understand the problem only after a mistake is made and the car loses stability or controllability. Most often, the response to an error is inadequate due to a lack of skill and the necessary protective control technologies.
But still, the beginning of all problems is associated with the psychological perception of the situation and the forecast of the possibility of negotiating a turn at the speed at which the driver begins this maneuver.
Security Forecast
Experienced racers, not jokingly, but seriously, believe that each turn has “its own last name, first name and patronymic,” or rather, a critical speed at which it can be overcome in accordance with skill, experience, condition of the surface and type of car.
Therefore, the first condition for the skill of predicting a situation is the driver’s ability to compare the geometry (steepness) of the turn and the speed of the car. Highly qualified rally athletes (international masters of sports) identify 18 (!) categories of turns starting from zero, where the road bend is so insignificant that it allows you to overcome it at a speed of over 200 km/h" and ending with the eighteenth, when the turn turns into a 180° turn and the car's speed drops below 40 km/h. Athletes at the master of sports level slightly simplify the assessment and distinguish up to 12 categories.
Experienced professional drivers and novice athletes believe that 7 categories are quite enough. In their version, a 90° turn has the serial number “5” and the critical speed for its passage ranges from 60 to 80 km/h, depending on the quality of the surface (ice or asphalt) and the width of the roadway.
The lower the driver’s qualifications, the more simplified and not always correct the assessment of the turn. Many quite experienced drivers believe that there are only 4 categories of turns: steep long, sharp and reverse. And the most inexperienced recognize only 2 categories: right and left.
| Category turning |
steepness, hail |
Critical speed, km/h |
Sequence of driver actions when entering at maximum speed | |
| For 4-speed gearbox | For 5-speed gearbox | |||
| 0 | 1-5,5 | 160-180 | IV-PR | V-PR |
| 1 | 6,0-11,0 | 140-160 | IV-TD-Z-PR | V-T-Z-PR |
| 2 | 11,5-33,5 | 120-140 | IV-T-Z-PR | V-T-IV-Z-PR |
| 3 | 34,0-56,0 | 100-120 | IV-T-III-Z-PR | V-T-IV-T-Z-PR |
| 4 | 56,5-78,5 | 80-100 | IV-T-III-T-Z-PR | V-T-IV-T-III-Z-PR |
| 5 | 79,0-90,0 | 60-80 | IV-T-III-T-II-Z-PR | V-T-IV-T-III-T-Z-PR |
| 6 | 90,5-135 | 40-60 | IV-T-III-T-II-T-Z-PR | V-T-IV-T-III-T-II-PR-TS |
| 7 | 135,5-160 | 20-40 | IV-T-III-T-II-PR-TS | V-T-IV-T-III-T-II-T-PR-I |
Notes
1. The table uses the following conventions:
I-V - transmission number; PR - steering wheel rotation; Z - loading of the front wheels; TD - engine braking; T - braking with service brake; TS - braking with parking brake; Gearbox - gearbox.
2. The critical speed range is related not only to the steepness of the arc, but also to the coefficient of tire adhesion to the road
But even a minor mistake in underestimating the steepness of a turn puts the driver in the face of a real critical situation.
Many times in my coaching career I have encountered such mistakes, even from experienced athletes.
At the Russian Rally Championship, in the right turn of category No. 3 (critical speed about 120 km/h), the champion in the Volga car class, Viktor Eremin, overturned four times. I was genuinely surprised by his crash in a completely standard corner, so I asked him to comment on his mistake. He explained to me that he had gone through this high-speed section twice in training and carefully dictated to the navigator the categories of all turns. But approaching this “unfortunate”, he caught up with the truck and, letting the oncoming car pass, crawled after it at a speed of 40-50 km/h. It was impossible to see the geometry of the road because of the dusty truck, and only after turning did he say to the navigator: “Write down the right one steeply, then we’ll check and clarify.”
During the inspection, the situation was completely repeated, only now two carts with hay were passing on the road and it was necessary to reduce the speed to a complete stop. When the navigator asked: “Shall we correct it or leave it as it is?”, Victor replied that there was no need to correct it. And already during the race, the navigator read the written term “Right one steep,” and Victor entered the turn at a speed of 155 km/h. And only after entering I realized that this was a turn of category No. 3 and a speed of 120 km/h was needed here.
With this example, I wanted to explain how an erroneous forecast leads to an accident even for experienced drivers. For those who have not acquired the necessary experience and mature caution, the best way out is to play it safe and over-braking before turning any category. There is always the opportunity to start accelerating earlier and return the extinguished speed. Probably, the Russian proverb will be true here: “The slower you go, the further you will go.”
Difficulty of turns
According to the method of passing, turns are divided into simple, complex and very complex. The differences between them are determined not so much by the steepness of the arc, but by the tactical pattern of the trajectory.
Simple turns of any category have a relatively short break and a constant radius. To navigate such a turn at high speed, two technologies are most often used. On an asphalt surface, after loading the front wheels with the weight of the car (engine braking after sharply releasing the gas pedal, engaging a lower gear at the last moment before a maneuver, the last braking impulse with the service brake), you need to turn the steering wheel quite sharply and immediately smoothly return it to the “straight” position. This maneuver can be called the “rotate-align” method. If the speed is low and there is no need to fear loss of control, both actions are performed smoothly, but the first part of the arc should be steeper than the subsequent one.
On a slippery road, when sharp steering can cause the front wheels to slip, the car turns at a minimum angle of rotation of the wheels due to sliding of the rear axle. A rear-wheel drive car is put into a measured skid by slipping the drive wheels, a front-wheel drive car is put into a measured skid by sharply releasing the gas at the beginning of the arc, or by using the “gas-brake” technique. This technique is performed without releasing the gas, and the rear wheels are blocked by braking with the left foot. A car with all-wheel drive is driven into a turn in one or the other way, but the first option involves slipping on all four wheels.
Complex turns differ primarily from simple turns in the length of the arc, i.e. between the turn of the car and its alignment there is an additional phase of movement along the arc. Therefore, here the method of passage can be characterized as follows: “turn - balance - alignment.” Each of the phases has its own characteristics and difficulties.
- In the first phase When entering the arc, a two-stage “smooth-fast” steering technology is used. At first the steering wheel turns softly. The car reacts to this with a slight roll, which “additionally loads” the so-called front thrust wheel (outer relative to the turn). This situation is used to quickly turn the steering wheel to the required angle. Although these two actions differ in the speed of execution, they must be inseparable. The ideal condition for entering the arc)" is the consistent use of the following techniques: "loading" (transferring part of the car's weight to the front wheels), "overloading" (shifting the weight to the thrust wheel), "sending to the arc" (turning the wheels to the required angle) and “traction” (pushing the drive wheels into an arc). Professionally trained racers say that this technology allows you to literally “screw in” into a turn, preventing the steered wheels from slipping. It is very important that at the entrance the wheels are turned to the desired angle, preventing further turning. in a turn.
- In the second phase When the car is held on an arc, it is important to create a traction balance that ensures the balance of the “car-road” system, correction of the trajectory and controllability of the car with short-amplitude steering actions. The method by which the accelerator can be used to keep a car on an arc without sideways slipping is called “zero” or “balancing” gas by athletes. Naturally, either the gas pedal is completely released or the gas pedal is pressed sharply on the arc will not allow maintaining this rather unstable balance. A fully released gas pedal on a front-wheel drive car is especially dangerous. It provokes the occurrence of a skid, and in some cases, the rotation of the car.
- In the third phase the vehicle is aligned for straight-line movement. It is accompanied by “yielding steering,” when the athlete prevents the wheels from self-aligning and smoothly increases traction. In this phase, sharp traction on a rear-wheel drive car creates a skid, drift of the front wheels on a front-wheel drive car, and a rhythmic skid on a car with all-wheel drive.
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On a slippery road, it is difficult to achieve effective loading of the front wheels and, even more so, redistribution of weight to the thrust wheel. Therefore, it is better to accompany the entrance to the turn by sliding the rear wheels. To immediately create the desired sliding angle, either a “counter-shift” (a smooth enveloping maneuver that rocks and turns the car at the entrance) or a “counter-skid” (a mini-skid to the side opposite to the turn) is used, turning the car with an intense overlap of the rear axle.
Directly on the arc of a complex high-speed turn, drivers of cars with different drive systems use different methods of passing.
- Rear wheel drive are held on a slippery road in a “controlled skid”, when part of the traction is used to move forward, the other part resists the centrifugal force. By slipping the rear wheels, the necessary balance of traction and the turning angle of the car relative to the trajectory are maintained.
- For front wheel drive two technologies are more typical. Either when the wheels are turned, the traction is adjusted so that excessive slipping does not straighten the trajectory of movement, or a polyhedron trajectory is built, when by sliding the rear wheels (the “gas-brake” technique), you can direct the car into the turn.
- For all-wheel drive Three technologies are typical. One is reminiscent of the technology used in rear-wheel drive cars and is accompanied by a series of skid-and-level actions. The other is similar to the front-wheel drive method, in which the wheels are turned inward and traction is limited by the angle of their rotation. The third method is typical only for all-wheel drive vehicles. The car is directed into the turn, and then powerful slipping of all wheels puts it into a controlled lateral slide.
Very difficult turns are characterized by a non-standard trajectory or an excessively long bend geometry. There are a great many models of such turns. Firstly, these are the so-called articulated turns with the same radii. One of the varieties of such a turn is the “hippodrome”. Rally drivers write it down in the transcript as a left 3-3-3. These types of turns are found on mountain roads with more significant steepness, for example, 5-5-5 or 4-4. Entering such a turn in excess of a critical speed automatically highlights an extreme driving mode on the arc on the verge of losing stability and controllability of the car. Standard braking techniques become dangerous, and athletes reduce speed by sliding the car sideways. This requires, above all, a level of skill. For a driver who is not too familiar with high-speed control technologies, it is best to use “over-braking” before entering such a turn.
Long turns with a smooth start and turn around the arc are even more difficult, especially in cases where they are closed for full visibility, which does not allow the driver to outline visual references for constructing the optimal trajectory. Looking ahead of the smooth arc, the driver enters the turn at high speed, not expecting that the steepness will increase. An experienced athlete, finding himself in such a situation, understands that if he tightens the wheels, he will lose control. Therefore, non-standard actions are most often used: straighten the area, apply the brakes and turn the car again; put the car into a deep skid to reduce the speed and direct the “face” of the car inward; cause the car to slide sideways and use it as a way to brake. You can, of course, try to brake with the service brake on an arc, but this braking must be measured, careful, and the force constant, so as not to cause the front wheels to drift or the car to skid.
It should be noted that the safest car in difficult turns should be considered front-wheel drive. It can be easily forced to slide with the rear wheels in order to turn it around the arc. But in order to do this, you need to master the “gas-brake” technology, which allows you to turn the car not with the front, but with the rear (!) wheels.
Another type of complex turns is S-shaped, when two arcs of different directions are connected by a common trajectory of the car. It is possible to build a safe trajectory on them due to a steeper maneuver on the first element, but not vice versa. If you quickly overcome the first part, then the final arc will have a greater steepness, and therefore a greater danger of losing vehicle stability when changing direction.
In many cases, drivers, without knowing it, turn a simple turn into a complex one due to inaccuracies in constructing the trajectory or due to errors in piloting technique.
The most common mistake- when the driver, fearing high speed, smoothly moves the car into the turn in advance and is forced to turn the wheels to a larger angle during the arc. Complicating the situation can also be associated with intense braking at the entrance to a turn, completely releasing the gas pedal on an arc, or sharp braking. These actions and many others do not allow the car to remain on the optimal trajectory and force the driver to make increasingly serious mistakes, which in high-speed mode throw him off the road.
Dangerous turns
If we consider turns according to the degree of danger, then we can distinguish three levels, each of which requires a certain psychological concentration, increased, and in some cases, extreme attention, error-free control actions and accuracy of the movement trajectory.
- First level- these are turns that do not yet cause acute stress, but are already alarming according to the forecast. For example, a moderately steep turn (category 1, 2 and 3) after a long straight requires increased attention, since you need to accurately determine the beginning and end of braking, the reference point for the start of the maneuver, and the nature of the trajectory. Prolonged movement in a straight line dulls attention, weakens the level of tension, and therefore an unprepared maneuver can cause inaccuracy in moving to the desired trajectory. The situation is aggravated by slippery surfaces, uneven entrances, poor quality tires and vehicle suspension, poor lighting and, most importantly, low skill levels.
An experienced driver before such a turn either reduces speed or increases the level of psychological tension (concentrated in proportion to the degree of danger and complexity of the turn). On a winding mountain or country road, increased attention is required when negotiating sharper turns, combinations of several elements, jumps and closed turns that are not fully visible. Right turns are considered more dangerous, since a gross mistake when passing them is fraught with entering the oncoming lane and the possibility of a head-on collision.
- Second level- dangerous turns, during which any mistake, even a minor one, immediately creates an extreme situation. The most common are dangerous turns with a low coefficient of adhesion (ice, snow, puddles, sand). The real danger is posed by road unevenness, especially in cases where they are under the “thrust” wheel (the front outer one relative to the direction of the turn). Tossing, bouncing and falling of a wheel into a hole immediately deprives the car of stability and controllability. Turns with a negative slope, on a descent, or at a turning point in the road (jump) are dangerous. Naturally, every difficult turn can become dangerous if there is an error in piloting.
- Third level- very dangerous turns in which high-speed traffic must be avoided. For example, a sharp turn, in the middle of which the rails of a railway crossing are raised high. If you enter such a turn at speed, the thrust wheel, loaded with the weight of the car, receives a crushing blow, the tubeless tire flies off the rim, and the disk (forged, stamped or any other) is destroyed and cannot be restored. But it happens that an injured disc is just the beginning of a problem that affects the car’s suspension elements, body side members, and steering rods. It can all end in a capsize on the roof. It is possible to overcome a very dangerous turn with uneven surfaces only after braking, almost until the car comes to a complete stop or to a speed at which an accident or breakdown of the car's chassis is excluded.
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Dangers created by the driver himself
Most of the problems of loss of stability and controllability of a car during a turning arc are created by the driver himself as a result of erroneous actions. Although all the controls - three pedals, steering wheel, two levers - are designed for optimal comfortable driving, each of these controls is fraught with potential danger.
Thus, turning the steering wheel further during the turning arc threatens to cause the front wheels to drift, braking with the wheels completely locked leads to longitudinal uncontrolled sliding, a sharp braking impulse provokes a skid, engaging a lower gear on the arc without re-gearing and delaying the engagement of the clutch creates a drift or skid depending on the characteristics drive the car, disengaging the clutch (coasting) leads to drift, releasing the gas pedal in an arc deprives the car of controllability.
If when driving in a straight line these errors are easily compensated for and eliminated, then when turning, especially at high speeds, they become the causes of serious accidents.
I remember one of these extreme situations, which we accidentally witnessed on an ordinary road under ideal driving conditions.
We approached a category 1 corner (critical speed of about 150 km/h) at a speed of just over 130 km/h with a large safety margin. A VAZ-2107 car began to arc towards us at the same speed. Not mastering the “loading” technique, the driver sent the car into the turn too smoothly and immediately released the gas pedal completely, fearing high speed. When the car began to spin out a little, he sharply turned the wheels inward and caused the front wheels to slide. Frightened by the squeaking, squealing of tires and the car skidding, he, instead of helping the car stay on the road with the engine's thrust, sharply pressed the brake and did not release it until the car stopped with a powerful blow to a century-old tree.
Although we passed each other on the road instantly, we immediately realized the danger of the situation from the preliminary maneuver and the incorrectly chosen trajectory. When the oncoming car disappeared from the view of the rear mirror, I immediately realized that misfortune could not be avoided. We immediately braked urgently and turned back. The sight was terrible. The tree entered the passenger compartment from the passenger side and tore off the right arm of a woman wearing a seat belt. She was unconscious because she received multiple head injuries. The man, who was not wearing a seat belt, was hit in the chest and all his front teeth were knocked out on the steering wheel.
Having broken down the passenger door, Evgeniy Barienikov, a teacher at the Center for Advanced Driving Excellence, and I first of all tried to stop the woman’s bleeding and, without removing her from the car, for fear of spinal injuries, we quickly bandaged her using bandages from two car first aid kits. Since at this early hour (4.30 am) there was not a single car on the road, E. Barienikov rushed for an ambulance, and I tried to help the man, who came to his senses. He tried to talk to me, I tried to check his reflexes for the possibility of a concussion or more serious injury. But, fortunately for him, he was slightly injured. What saved him was that he rested his hands on the steering wheel during the impact.
But overall, the outcome of his trip was disastrous. A driver with more than twenty years of experience was not technically and psychologically prepared for a not-so-difficult road situation, and aggravated it with his actions.
Fast cornering
When driving through a city intersection, or slowly moving in traffic along a winding country road, we usually do not think about any special control technologies and optimal driving trajectories. But in vain! By winding kilometers of road on the wheels of a car, we form our own driving style, and repeating it many times, we practice correct and sometimes incorrect actions, which in critical situations throw us off the road to the side of the road or, even worse, into oncoming traffic.
The main safety regulator when cornering is speed. Raising it from minimal to critical, we consistently move from a zone of relative safety to a risk zone, and then to an extreme one. God forbid, into a catastrophic one. Under normal conditions (relative safety zone and low-speed traffic), the mistake made can be corrected in different ways:
- tighten the steering wheel if you do not fit into the turn;
- change gear if you forgot to do so before turning; release the gas pedal if the speed is too high;
- Brake to a complete stop if necessary.
| Danger level | Safely | Attention! | Dangerous!! | Very dangerous!!! |
| Security zones | Relative safety zone | Risk area | Critical zone | Emergency zone |
| Driving conditions | Normal | Complex | Extreme | Catastrophic |
| Characteristics of driving conditions | Consistently favorable conditions for all components of the VADS system (driver’s condition, pavement characteristics, technical condition of the vehicle, driving mode within the framework of traffic rules, unloaded traffic, illumination, absence of external interference, etc.). | Negative changes in objective and subjective factors (exceeding the optimal speed limit, shortening distances and intervals, limited or deteriorated visibility, decreased friction coefficient, traffic violations, technical malfunctions of the vehicle, decreased driver performance, difficult weather conditions | Sudden loss of vehicle stability due to errors in forecasting or control, gross traffic violations, failure or damage to vehicle systems, time and distance limits, stress, loss of performance due to illness or alcohol intoxication | Complete loss of stability and controllability, vehicle movement according to the laws of ballistics, psychological refusal of control (“motor shock”, inability to stop due to lack of time and distance, gross error in extreme conditions. |
| Features of control techniques | Standard, rational, elementary in coordination of movements and unlimited in time. | Anticipatory, compensatory, dosed in time and effort. | Non-standard, variable, creatively designed techniques from the existing arsenal in relation to specific conditions | Extraordinary. Self-insurance system, including measures to mitigate the consequences of road accidents |
In the risk zone (high-speed traffic, low coefficient of adhesion), the control action program has many limitations, and any, even minor, error deprives the car of stability, controllability, or both at the same time.
If you turn the steering wheel sharply on a slippery road when entering a turn, you will create a “drift”—the front wheels slipping.
If you turn the steering wheel even more to stay on the road, you will end up with an uncontrolled sliding forward.
If you press the brakes sharply and lock the wheels, you will slide straight, despite the turned wheels.
Release the gas completely - you will feel the car moving to the outside of the turn on rear-wheel drive or skidding on front-wheel drive.
If you press the gas pedal sharply, you will get a skid in a rear-wheel drive or all-wheel drive car.
To avoid all these misfortunes, you need to have a clear forecast of the car’s behavior in relation to your own actions in order to prevent mistakes, or a level of driving skill at which you can maintain stability and controllability using special techniques - methods of self-insurance.
A mistake made in the risk zone immediately sends us to the zone of critical situations: lateral or longitudinal sliding, critical skidding, rotation and even capsizing.
A motorist without experience and without special training is doomed to failure because only correct reflex actions brought to the point of automatism can save them. If one of the “inexperienced” overcame such a situation, then we can consider it pure luck. Most often, in such situations, the driver does something that should not be done: he brakes sharply, reacts with the steering wheel in the opposite direction, sits in the pose of an idol, constrained by stress and confusion.
Even highly qualified racing drivers cannot always overcome dangerous situations created at critical speeds associated with the rotation of the car. But they cannot be accused of incompetence and lack of understanding of their car and the competitive situation. Riding at the edge of human capabilities constantly forces them to be at extreme risk. The nervous system is dulled by extreme psychological stress and reacts to a mistake with a delay of 0.01-0.02 seconds. This delay often cannot be corrected to restore the car's lost stability.
After an extreme traffic zone, when it was not possible to correct the situation, we immediately find ourselves in a catastrophic zone, when the car slides or flies off the road surface (depending on the initial speed) to the side of the road. In order not to have to repair the car and resort to the services of doctors, in this zone you need to continue to actively fight for safety, and not sit in shock, passively observing the behavior of your car. In most cases, you need to force yourself to release the reflexively pressed brake pedal in order to move from an uncontrolled ballistic slide to maneuvering, dodging trees, poles and other obstacles.
If an accident cannot be avoided, you need to try to avoid a frontal impact - the most dangerous situation for the life and health of the driver and passengers. Where the brake does not help, you need to apply emergency contact braking, crushing the corners of the bumper and the front wings of the car against obstacles. These parts contain the energy-absorbing properties of the passive safety of a modern car.
Falling out of the trajectory during a turn, some drivers are faced with the problem of rollover. Most often, they themselves provoke it with their wrong actions. When a careening car rolls to the side of the road, the driver turns the steering wheel to return it to the road. This is where the error lies. Remember your actions when you were riding a bicycle or motorcycle. To avoid falling when tilting sideways, you need to turn the steering wheel in the direction of tipping. The motorist needs similar actions. First, turn the steering wheel in the direction of the tilt, and only after the roll has been extinguished and the car has four points of support, return it to the road. This recommendation is difficult to implement, because it involves first refusing to return to the road and directing the car into an area of impending danger. But there is no other way out. Otherwise, you will have to tumble through the roof and at the last moment remember that you are not wearing a seat belt, which is so necessary in such a situation.
Turning on slippery roads in winter conditions is especially dangerous. This danger increases significantly on all-season and, even more so, summer tires. The front steered wheels become “vulnerable”, and a sharp turn into a turn can create a partial loss of controllability - the phenomenon of “driving” of the front wheels. Most often, an inexperienced driver reacts to the car’s reluctance to start turning by reflexively turning the wheels to an even greater angle, which intensifies the “drift.” This error is usually followed by the next one - sharp braking, leading to longitudinal sliding with complete blocking of the wheels. As a result of a chain of consecutive errors that were imperceptible under normal conditions (dry asphalt), the car already at the beginning of the turn falls out of the desired trajectory and, sliding, goes to the side of the road.
High speed approaching a long or sharp turn provokes the driver to make another common mistake - early shifting of the car to the inside radius. Pressing immediately inward, the driver is forced to start the turn with a small angle of rotation of the wheels, and as the turn unfolds, turn the steering wheel in an arc. This is playing with fire, especially in cases where you need to slow down. Steeply turned wheels in the middle of an arc, and even against the background of braking, instantly create a drift of the front wheels. Then most often follow the erroneous actions discussed in the previous episode, and the result is an uncontrolled longitudinal sliding onto the side of the road or into the oncoming lane.
Fast cornering creates conditions for unstable vehicle balance. Even a slight roll, which cannot be avoided, loads the outer wheels with the weight of the car and unloads the inner ones. Therefore, when turning, the wheels react to control actions differently.
Excess or lack of traction, and even more intense braking, lead to skidding of the rear axle. A front-wheel drive car can react by skidding when the gas pedal is released, a rear-wheel drive car can react to excessive traction (wheel slip), an all-wheel drive car is less predictable - it can react as both front-wheel drive and rear-wheel drive. The angle of the skid depends on the duration or severity of the error, and if self-insurance actions are not taken (the driver’s reaction to the skid), the car may go into a rotation or rhythmic skid with a lateral slip of the rear axle.
Anti-traction and anti-lock braking systems help to avoid gross mistakes when turning. However, they are intended only to insure against an error, but if it does occur, then the same systems will prevent the driver from taking active steps to stabilize the vehicle that has lost stability and controllability.
Racing drivers believe that this is the driver's skill (an arsenal of control techniques), the feeling of the car as its own body and the prediction of the car's behavior in response to control actions.
If today you cannot yet boast of such qualities, then do without sharp experiments, slow down before turning, or at least concentrate if you did not have time to do this. Remember that speed does not forgive mistakes, therefore, by controlling the speed limit in a turn, you control your safety within the limits of your existing skill and the actual situation on the road. Don't rely on intuition unless you have significant ones; high-speed driving experience. Intuition is an unreliable “lady”; it often depends on a person’s psychological state, positive and negative emotions and many other factors. Turn on your favorite music louder, take your mind off the road a little, talk to a passenger, and immediately your intuition will fail and miss the danger signal.
The lower the skill level, the more important the forecast. There are many examples where, with “zero” training, drivers never get into emergency situations. You need to take your hat off to such drivers and be amazed at their ability to guess the criticality of the situation even by indirect signs.
Therefore, constantly train and practice smooth, soft actions with the controls. These skills will be very useful to you when driving at high speeds; they will allow you to maintain the balance of stability and controllability inherent in the design of any car.
Even in a pre-critical situation with a shortage of time and distance, when you realize that the speed is too high, restrain yourself from sudden actions with the controls in a turn.
Cornering technique
The term “technique” refers to an arsenal of driving techniques that can be used to overcome turns of varying steepness and complexity with completely guaranteed safety. Even if you are a careful, prudent, attentive person and use your car only as a means of transportation, trying to stay away from stress, hectic chases and car racing, you still need to get acquainted with the ABCs of high-speed driving. Don’t expect that the most modern car, stuffed with computer and mechanical active safety devices (automatic transmission, power brake and steering, traction control and anti-lock braking system ABS, limited slip differentials, steering and stabilizing devices, etc.), will save you from troubles. Rely only on yourself, on your strength, knowledge, skills and abilities, because there are no ideal drivers. But a professionally trained person behind the wheel, predicting road conditions, will try, using technical techniques, to either avoid or overcome a critical situation and correct the mistake.
Normal driving does not require any special control technologies, because even a relatively serious mistake can be corrected in the turn itself by reducing speed or repeating the maneuver if the first one was unsuccessful. But there is one very serious problem, which in a difficult situation can lead to a blunder and an accident. This is the learning of non-technical and erroneous actions that create apparent comfort in easy conditions. Among them are holding the steering wheel in the lower sector, changing gears during a turn, sharp braking, turning the steering wheel further during the turning arc, etc. Performed day after day, these elements and techniques ultimately form a potentially dangerous driver. The most surprising thing is that many do not even suspect that their driving style is fundamentally flawed, and do not accept criticism.
Several years ago, at the request of Pepsi-Cola, we trained employees in Samara. We were met at the airport by one of the company's most experienced drivers with extensive experience. The road from the airport to the destination ran through the Zhiguli Mountains. It was not specifically mountainous, but still had a lot of turns on the ups, downs and flats. The driver knew the road very well, and we drove at a speed of 100-110 km/h. Approaching the first turn, we - four teachers from the Center for Advanced Driving Excellence - received nervous stress when the driver put the gear in neutral before the turn, and the car coasted into the arc. After the turn, he shifted back into fourth gear. Our “ace” performed the same actions at every turn. We grabbed all the handles, pressed our feet into the floor, and pulled the inertial seat belts to make them work. Don't think we had an accident. This did not happen, and it must be said that the driver never slipped or got into a skid. But is it possible to joke like that with your safety? After all, by disconnecting the engine from the transmission, we lose the main opportunity to regulate the stability and controllability of the car.
We have already said above that there are up to 18 categories of turns according to the steepness of the trajectory and many more additional features that make turns difficult, very difficult, and sometimes dangerous. Although control technologies in different turns, with different coefficients of adhesion, on different cars and by different drivers may differ, there are general patterns and standard actions, without which it is impossible to create a guaranteed level of safety. We call these basic techniques - the ABCs of driving skills. An experienced professional, and especially a racing driver, always uses them in both low-speed and extreme driving modes. In this way, a reliable management style is created and a person does not need to have two faces, one relaxed and imposing, and the other aggressive and sporty. It is best to own one universal technology that is suitable for any conditions, including extreme ones.
Phase nature of turns
When naming the basic techniques of skill necessary for passing turns, you should immediately clarify the presence of four phases of passing. In motorsport these are referred to as the approach, corner entry, arcing and exit phases.
Approach phase
Most often this is a straight section of the road that precedes the turn itself. In this phase, it is desirable to assess as early as possible the real category (steepness) of the turn, determine the critical speed of its passage, predict the degree of danger and mentally construct an optimal trajectory, determining, if the turn is open, specific landmarks for braking and starting the maneuver.
Braking before a turn
The braking method (standard, intensive or emergency) is selected depending on the speed of movement and the distance to the start of the turn. If you need to reduce the speed by more than 40 km/h, increased attention to this operation is required. Depending on the coefficient of adhesion and the presence of irregularities, a braking technique is selected with constant or pulsed application of force (intermittent, stepwise, or a combination of techniques: smoothly, intermittently, stepwise, called variable braking). On cars equipped with ABS (anti-lock braking system), under standard conditions they use a small force that does not turn on ABS, and in extreme conditions they turn on the system with a strong press. By turning on ABS, the driver is, as it were, removed from control, because it is impossible to predict the dynamics of deceleration, which is controlled by the computer according to its programs, one of which monitors directional stability and can reduce the braking effect in response to slippery surfaces.
- complete braking before starting the maneuver, since braking on an arc is much more dangerous due to the unequal lateral loading of the wheels;
- stop braking before starting the maneuver, since in the entry phase the steering wheel and brake act as antagonists. Either slow down, but go straight; or turn, but without braking. A compromise is possible on cars with ABS; here you can brake and turn, although this is not so easy.
Downshifting before turning
Unfortunately, this technology has been completely lost by ordinary drivers and remains only in the arsenal of racing drivers. We have long been accustomed to braking in the gear in which we are driving, and we engage the gear only after the engine has lost speed and dynamics.
Consecutive engagement of lower gears will allow:
- reduce the risk of blocking the drive wheels, which is especially important for single-wheel drive vehicles;
- “charge” the car with engine torque. This thesis requires special explanation.
Engine torque (in a simplified sense, “thrust”) corresponds to certain speeds. For example, for the VAZ family this range is from 2500 to 4000 rpm. In this mode, the engine responds well to the gas pedal. By releasing the pedal, you can load the front wheels, by pressing, you can add traction, and by alternately working the pedal you can adjust (!) the balance of stability and controllability in the turning arc. By selecting the right gear before a turn, we create additional safety features. By losing engine speed when braking in a constant gear, we deprive ourselves of the opportunity to overcome difficult situations.
- combined braking before a turn with sequential engagement of lower gears is used for intensive or extreme deceleration of the car;
- in order to prevent lateral slipping and “yaw” of the car when shifting gears, it is advisable to use “re-gearing” (raising engine speed before shifting gears);
- the choice of the required gear is determined by the steepness of the turn;
- after engaging a downshift, the engine should not lose “torque”;
- The ideal situation for high-speed cornering is when the gear is engaged at the last moment before the maneuver and provides additional load on the steered wheels;
- It is advisable to gently release the brake pedal before turning in order to maintain the stability of the car;
"3rd approach" to the turning arc
A smooth maneuver performed before a turn to increase the radius of the arc and reduce the effect of centrifugal force on the vehicle. “Approach” is an element of the so-called “smoothing trajectory” - the fastest and safest, i.e. Before turning, the car must be moved as far as possible to the outside. Racers use the entire roadway for this, rally drivers manage to drive onto the opposite side of the road, and an ordinary driver can only use the width of the lane (3.75 m) so as not to come into conflict with the traffic police traffic police.
The higher the speed, the more relevant this maneuver is for creating an additional safety reserve. Inexperienced drivers most often do everything “exactly the opposite.” This trajectory error leads to drift of the front axle, which intensifies if sharp braking is applied.
- the steeper the turn, the more the car should be moved to the outside of the trajectory before starting the maneuver;
- at high speeds, you need to avoid the mistake of early shifting inward and force yourself to perform an “entry”;
- in urban conditions, a small “approach” will eliminate the possibility of hitting the sidewalk curb with the rear inner wheel, a wide “approach” to the second lane will make your maneuver incomprehensible to the driver behind you, and an inexperienced person will try to push his car into the resulting gap;
- if possible, the “entry” should be done early and quite smoothly. A sharp “entry” at the last moment can create the effect of rocking and skidding of the car in the phase of entering the turn.
Turn entry phase
When driving at low speeds, to move the car into a turning arc, just turn the steering wheel to the desired angle and wait for the car to react, which will follow immediately. Many uninformed drivers try to use the same technology at high speed and often encounter a phenomenon where the car is reluctant to respond to the steering wheel or begins to slide the front wheels out of the intended path.
Sports practice has created a whole series of options for entering a turn, depending on the speed and coefficient of adhesion.
Options for entering a turn differ in the method of execution:
- smooth entry is used before small turns or on slippery roads, when it is very important to prevent the front wheels from sliding sideways;
- sharp entry is a maneuver limited by the time frame (OD - 0.12 s) of artificially loading the front wheels with part of the vehicle’s weight after stopping braking;
- deep entry - a maneuver that is late in time and allows, using the maximum load, to make the first part of the turn steeper, and the subsequent one safer by increasing the radius;
- entry with power sliding - used by racers in road racing with the transfer to controlled sliding of the front wheels with a lateral slip from 6° to 10°.
- entry with skidding of the rear axle - used on slippery roads as a necessary measure to increase safety. It can be used as a method of unconventional braking in the movement phase, when braking with the service brake becomes dangerous and the speed is still high. Most often, this method is used by rally drivers and racers on the track in order to maintain controllability of the front wheels and avoid drift of the front axle due to a slight loss of stability.
Management techniques
Although the entry phase is short in time, it is very significant in maintaining or losing stability and controllability of the vehicle. It is not always easy to transfer a car moving at high speed in a straight line into a turning arc, because the beginning of constructing an arc of safe or dangerous movement in a turn depends on the accuracy of the driver’s control actions. During the entry phase, the following techniques are used:
. To ensure that the front wheels remain in control, one of the braking techniques is used to create additional downforce on the front wheels. According to the degree of effect obtained, this is either engine braking in a constant gear, or braking with a service brake. In the latter case, the driver uses the effect that remains on the front wheels when the brake pedal is released. The duration of loading during engine braking depends on the type of drive. The shortest - 0.08 s - for all-wheel drive, the longest - 0.1 s - for front-wheel drive and the longest - 0.12 s - for rear-wheel drive.You can log in “on boot” using the following control actions:
- "loading for gas release". At the same time, the gas pedal is released and the steering wheel is turned. Since the action of the braking forces is somewhat delayed, the pressing of the wheels occurs at the moment of the full amplitude of rotation of the wheels. On cars with an automatic transmission, which have some "thoughtfulness", the gas pedal is first released, and a short pause is followed by steering action.
- "loading" to engage a lower gear. The complexity of this technique lies in the fact that the gear must be engaged at the very last moment before the turn, which is not possible for an ordinary driver, but is quite possible for racers. That is, the signal to turn the steering wheel is the moment the clutch pedal is released.
- "loading" by braking. To take advantage of the moment when the front suspension springs have not had time to straighten and deprive the car of additional load, the signal to turn the steering wheel is to start releasing the brake pedal.
- increasing the car's steering ability. The design of any car has the properties of oversteer or understeer, or a certain balance of these properties. Thus, sports and racing cars are most often tuned to understeer to drive at maximum speeds. If you install outer wheel rims from a rear-wheel drive car on a serial front-wheel drive car, it will acquire obvious oversteer properties. In pursuit of fashion, many drivers are forced to hold such a car on the road with both hands, since it reacts with a “yaw” even to a slight release of gas.
There is another property of a car that makes it difficult to turn at high speed. These are gyroscopic (stabilizing) moments of rotating wheels. To sharply send a car into a turn and create such an effect when the car literally “dives” into an arc, you need to use the “loading” technique, which, in addition to transferring weight, allows you to:
- reduce gyroscopic stabilization using braking;
- increase steering by compressing the front suspension.
Precise steering actions.
Depending on the speed of the vehicle and the coefficient of adhesion of the tires to the road, several steering methods are used:
- on a slippery road, the steering wheel turns very smoothly and the angle of rotation of the wheels is limited to prevent them from sliding sideways;
- on a dry road, if there is no need to apply braking, the steering wheel is turned smoothly and continuously until the optimal angle of rotation of the wheels. Stepped steering (turn - pause - turn) is undesirable at any speed, with the exception of slow "yard" maneuvering;
- entry at high speed into a standard gentle turn, where there is no need to intercept the steering wheel, is performed sharply after loading, and leveling is smooth, simultaneously with an increase in traction;
- Entering a tight turn is done with a two-stage steering speed after loading. At first, the steering wheel turns smoothly to create a roll of the car and transfer weight to the “thrust” wheel (the front outer one). Then, without a break in time, the steering wheel turns quickly to the final (desired) position in order to eliminate the need to turn the wheels on the arc. This is extremely undesirable, since the loading effect will be less than at the entrance to the turn, and an additional turn on the arc can provoke a slip;
- loading - turning - traction. Although we separately considered loading options, without subsequent traction, controllability on the arc will be reduced. Driving in an arc with the gas pedal released will cause the car to move outward. Therefore, when a driver releases the gas out of fear, or even worse, brakes after entering a turn, he himself creates a critical situation;
- in a gentle turn, after loading and turning the wheels, thrust is immediately sent to the drive wheels. By aligning the wheels, the traction is increased so that when the wheels are in a “straight” position, it is brought to the maximum;
- in a sharp turn with a long arc, after loading and turning the wheels, limited traction is sent to the pulling wheels, depending on the angle of rotation of the wheels. More angle means less thrust and vice versa;
- if loading is performed by braking with the left foot, then the gas pedal is not released when entering a turn, and the increase in traction is regulated by delaying the release of the brake pedal;
- Counter offset. This term refers to a special maneuver that allows you to additionally turn the car at a certain angle when entering a turn on a slippery road. Before the main action (turning the wheels onto the trajectory), a smooth enveloping maneuver is performed in the direction opposite to the turn. Following this, the actual turn is performed, but rocking the car with two maneuvers (countershift and turn) allows you to artificially create a slip of the rear axle to the desired angle. The phenomenon that occurs in this case is called “dynamic whip”;
- counterskid. In slippery road conditions, when it is necessary to enter a turn at a supercritical speed (for example, the critical turning speed is 110 km/h, and on the approach the actual speed is 150 km/h), a special technique is used that allows you to turn the car to the desired angle | to use sideslip as a braking method. The technique is performed according to a scheme similar to the counter-shift, but unlike it, in the first phase it is not a rolling maneuver that is used, but a small angle of measured skidding. By rhythmically rocking the car, you can create any sliding angle during the entry phase, up to a 180° turn;
- entering a turn with the rear axle skidding. This technique is forced to use external conditions and, in particular, a very slippery, icy road. When sending the car into an arc by turning the front wheels, an experienced driver is afraid of their lateral sliding (drift). On dry roads, you can use loading so as not to lose control at the very beginning of the turn. On slippery roads, such capabilities are limited and you should look for other control technologies. One of the ways to maintain controllability is measured sliding of the rear wheels (controlled skidding). This option allows you to turn the car to the desired angle with minimal wheel rotation angles. The secret of the technique is that by losing part of the car's stability (creating an artificial skid), the driver is guaranteed to maintain controllability, avoiding a large amplitude of rotation of the front wheels. The technique for performing the technique varies depending on the characteristics of the drive.
REAR DRIVE. The transfer of the car into a controlled skid is caused by slipping of the rear wheels after the car “accepted the maneuver”, i.e., reacted to the turn of the front wheels. Dosing the skid angle is carried out by one or several successive pulses of pressing the accelerator pedal.
FRONT-WHEEL DRIVE. Putting the car into a controlled skid is caused in one of three ways:
- Completely stopping throttling (releasing the gas pedal) after turning the steering wheel;
- Using the "gas-brake" technique (braking with the left foot while pressing the accelerator pedal);
- By briefly turning on and off the parking brake with the wheels turned;
FOUR-WHEEL DRIVE. The transfer of the car into a controlled skid is caused either by a short slip of the four wheels after the car is aimed at the arc (a longer slip can cause longitudinal sliding due to slipping of the front wheels), or by briefly applying the parking brake, if the inter-axle locking allows this.
Phase of movement along the arc of rotation
Driving a car in a turning arc at high speed, significant steepness and insufficient coefficient of tire adhesion with the road is complicated by the need to keep the car on a given trajectory, the influence of centrifugal force pushing it outward, and the uneven loading of the wheels with the weight of the car (the outer ones are more loaded than the inner ones relative to the turn) . To maintain stability and controllability at high speed, professionally trained drivers use the following techniques:
- hand position in a turn. If, when moving at high speed in a straight line, the ideal position of the hands is at position 10-2 (according to the clock dial), i.e. symmetrically in the upper sector of the steering wheel, then in a turn it is desirable to shift them towards the turn. When turning right, the left one is in position 12, and the right one is in position 4, when turning left, the right one is 12, the left one is 4. What is achieved by this position?
- Oddly enough, but psychologically it is natural when our hands show us the direction of movement and allow us to return the car to the “straight” position after the maneuver. And, on the contrary, it is unnatural when the hands are positioned symmetrically when turning (for example, 9-3).
- When bent at the elbow joint and shifted to position 4 or 8 (depending on the direction of rotation), the hand with strong flexor muscles prevents the steering wheel from self-aligning, and the other hand, located on top, helps it in this.
The position of the hands creates a good opportunity not only to return the car to straight-line motion, but also to instantly and sharply react to its possible skidding with an outward movement (reaction to skidding).
- Preliminary capture. An experienced driver tries to turn the steering wheel without intercepting his hands, so as not to lose control over the position of the wheels hidden by the car’s wings, and immediately after the maneuver return them to the “straight” position. However, in sharp turns when steering without interception, both hands shift and cross to the lower sector, which is extremely undesirable and even dangerous. To eliminate such situations, the driver, before starting to taxi, moves one of his hands by sliding along the rim of the steering wheel, thus increasing the amplitude of steering without interception.
- Shifting the main hand (the one that will turn the steering wheel by pulling the flexor muscles down) until it makes contact with the auxiliary hand. For example, before a right turn, the left hand remains in position 10, and the right moves towards it either slightly or closely. In some cases, capture can be carried out at points 9, 8 and 7, i.e. below the auxiliary hand.
- Shifting the auxiliary hand is used in cases where it is initially clear that the main hand will not have enough amplitude of rotation to the desired angle or if it ends up in the lower sector. Shifting the hand in the opposite direction from the turn is done by sliding it along the rim of the steering wheel before the maneuver begins (for example, when making a right turn, the left hand drops to point 8). There is another way to change the position of your hand. When the main hand begins to pull and moves along with the rim, the auxiliary hand remains in its original position, weakening the grip, i.e., the steering wheel slides inside the unclenched hand. As soon as the main hand moves to the beginning of the lower sector, it is freed from traction and the auxiliary hand comes into action. The released main one can intercept in the upper sector, or maintain its final position if taxiing is completed.
- Taxiing on a turning arc. In the ideal theoretical version, at the entrance to the turn the steering wheel turns to the desired angle, this angle is maintained during the arc, and at the exit the wheels smoothly align to the “straight” position. In real conditions of high-speed traffic on a turning arc, the hands non-stop perform the work of “steering”, trying to keep the car on a given trajectory. This need arises due to the fact that the car is in unstable equilibrium (the centrifugal force of inertia loads the outer wheels relative to the turn; the resulting roll forces the side suspension to work intensively and react sharply to any irregularities; a high-profile standard tire, deforming, creates the effect lateral slip; the thrust wheel (front outer) changes the contact patch with the road in the direction of movement. All of these phenomena and many others associated with the operation of all vehicle systems create a certain imbalance in stability and controllability and require its correction using the steering wheel.
The lower the driver’s qualifications and the later he feels the car’s reactions, the greater the steering amplitude is needed.
In many cases, when the centrifugal force exceeds the traction capabilities of the wheels, side skidding or apparent sideslip occurs. It primarily affects the turned front wheels (drift phenomenon). The car signals the driver about this phenomenon by squeaking, squealing, and then loudly squealing tires. It should be noted that a professional, even before the sound of the tires, can recognize the beginning of a loss of controllability by “light steering” (the cessation of the desire to self-level).
We often hear the squeal of wheels in American action films associated with chases; many are familiar with this phenomenon in real life, especially on mountain roads. Outwardly, it seems that this is a superman racer rushing, fearless and swift. In fact, this is not skill, but a bluff. It’s not a master who’s coming, but an ordinary “teapot.” His car cries, screams and, most importantly, loses speed, because... strongly turned wheels act as brakes.
In their practice, racers use the so-called power sliding, when the angle of rotation of the wheels exceeds the trajectory angle by no more than 5°. But their sporty low-profile tires allow you to maintain full controllability in the turning arc.
- throttling on the arc of rotation (engine thrust control). It is probably not very correct to consider working with the gas pedal in a turn without steering, because these two controls are, in total, the orchestra of two instruments that the driver conducts for the benefit of his safety.
The balance of stability and controllability of the car when cornering depends on the accelerator pedal. But under one important condition: when the engine is operating in maximum torque mode (as mentioned earlier, for the family of serial VAZs this is the range from 2500 to 4000 rpm). On sports cars, engine torque ranges depend on many parameters: engine cubic capacity, piston stroke, valve timing, on-board computer settings, etc. So, for example, for two-liter VAZs with an Opel engine, the torque range is from 6000 to 8000 rpm, for engines 1600 cm/cc, from 5500 to 9500 rpm. For turbocharged gasoline engines, powerful thrust begins after the turbine starts in the range from 2100 to 7000 rpm. Working in optimal traction mode, the accelerator pedal allows you to regulate the car's steering (decreased traction - oversteer, excess traction - insufficient).
If, when driving in a straight line, the accelerator pedal allows you to regulate acceleration, deceleration and maintaining speed, then in a turn, especially at high speed, it, like a tightrope walker’s balancer, ensures the balance of the “car-road” system. In the sports terminology of racers, the expression “balance gas” or, in another version, “zero gas” is often encountered, implying very delicate work to maintain stability and controllability.
The amount of throttling depends on the angle of rotation of the wheels. The greater the angle of rotation, the less thrust. Most often, in high-speed mode, variable throttling is used rather than constant throttling due to the fact that, due to the tire slippage, the contact patch changes along the direction of travel. In a rough version, this is a sharp release of the pedal and pressing it again; in a more subtle version, it is the “more-less” mode. Top-class racers strive for constant speeds throughout the turning arc and briefly reduce them only at the moment when the car veers off the line.
The accelerator pedal allows you to compensate for errors in steering on an arc when the front wheels slip sideways, but most often these two controls complement each other and work synchronously. So, for example, if the front axle is demolished, the traction and steering angle of the wheels simultaneously decrease.
With a low speed of movement and stable balance, there is no need to use any special techniques and technologies. You can use slight steering at constant engine speeds. And at a constant angle of rotation of the wheels, the work of the accelerator pedal is small in amplitude. Increasing the speed to critical requires finer coordination of actions and compensation for errors, which are quite possible due to changes in the coefficient of adhesion (unevenness, slippery surfaces, quality of shock absorption capabilities).
In extreme mode, when traction is possible. front wheels are limited and increasing the angle of rotation will lead to their slipping, the accelerator pedal allows you to use additional extraordinary actions - steering with the rear sliding wheels. For rear-wheel drive vehicles, this is a controlled skid caused by arbitrary slipping of the drive wheels; for cars with front-wheel drive, this is the lateral sliding of the rear wheels using the “closed gas” effect when they are blocked by braking with the left foot or applying the parking brake; for all-wheel drive vehicles, this is a combination of methods and techniques for single-wheel drive vehicles.
The accelerator pedal allows you to use active safety techniques in situations of loss of vehicle stability, for example, when the rear axle skids. However, each of the drives (front, rear and all-wheel drive) requires its own version of these actions. So, rear-wheel drive will allow you to maintain stabilization by completely stopping throttling (“close the gas”), front-wheel drive will increase traction, and full-wheel drive will reduce traction, but not stop it completely. An error in the reaction to a critical situation most often causes additional torque, and the use of braking instead of the necessary traction leads to a lateral slip of the car.
Unlike steering technology, in which, with the exception of sliding phases, the vehicle's reaction is instantaneous, actions by the accelerator pedal are delayed (inertia of the fuel system) and therefore must be advanced. The system of cars with automatic transmission is especially passive, and the leaders in this passivity are cars of American manufacturers, which are clearly not ready to act in critical situations.
Sport-racing mode is the most complex throttling technology because... slippage and insufficient traction are two extremes that must be avoided. The compromise, which ensures maximum speed in a controlled slip mode of the front wheels, is achieved by the driver's subtle senses and advanced reactions to the car's behavior. Athletes in pursuit of maximum speed in corners most often use two technologies for controlling the accelerator pedal: “driving on torque” and “driving at maximum speed”. The first one is simpler, because used on vehicles with a wide range of traction. The second is more complex and requires engine settings, selection of gearbox gears, changes in body aerodynamics, and suspension adjustments for a specific race track. In some cases, especially on cars with limited engine capacity and short piston stroke, the “motor geometry” technology is used. This is the choice of such a trajectory of movement in which it is possible to maintain traction in a very narrow operating range.
Exit phase
Although the final part of the turn is simpler in the nature of control actions than the previous two, it has a number of features that affect safety. Most often, problems arise due to the fact that it is necessary to eliminate mistakes made earlier (car drifting away from the optimal trajectory, loss of engine thrust, partial loss of stability and controllability).
Under ideal conditions, the trajectory levels out very smoothly. At the same time, the driver prevents self-leveling of the steering wheel by weakening his hand grip. It is advisable to mirror the taxiing in the reverse order. If, when entering a turn, it was necessary to apply an active force to turn the steering wheel, now you need to apply braking to return it to the straight position. The fuel supply also increases smoothly, gently and continuously, so that, if we are talking about high-speed driving, by the time the wheels are brought to the “straight” position, the engine reaches maximum speed. If one of the lower gears was used while moving along the arc, then upon completion of the exit the higher gear is immediately switched on.
One of the outstanding racers of the 80s, E. Tulenkov, recommends: “Before you press the gas pedal to the floor, return the center of gravity under you.” In this, at first glance, incomprehensible phrase lies a deep meaning in constructing an exit trajectory. While the car is on an arc, the center of mass is shifted outward, and if you give powerful or sudden traction, the drive wheels will slip. For a front-wheel drive vehicle this is a stalling of the front wheels, for a rear-wheel drive vehicle it is a skid of the rear axle, for an all-wheel drive vehicle it is a sideways slip of the entire car or a skid in those models where most of the engine torque is transmitted to the rear axle (30x70 or 40x60 options). In order to use full traction earlier, you need to “unfold” the trajectory, that is, direct the car outward. This maneuver is the logical conclusion of the so-called “smoothing trajectory”, the elements of which are “entry”, “cutting” and “blooming”.
In the heat of the competition, many inexperienced riders make a mistake on the exit, when the early application of maximum traction leads to a rhythmic skidding of the rear axle, and then to a rotation after the turn. For untrained drivers, this situation often occurs during sharp maneuvers on a straight line and during any phases of a turn.
The roots of this situation among athletes are associated with psychological unpreparedness for extreme actions in the phase when the turn is almost completed and there is no sign of loss of stability. A skid takes the driver by surprise, and actions with a slight delay and insufficient steering speed create a promise for the next skid, but in a different direction. For an ordinary driver who does not have high-speed steering skills in his arsenal, the situation with the rear axle swaying is quite natural due to untimely actions, technical errors, passivity and slow motor reactions. A high-class racer in any phase of cornering is “charged” for a certain reaction and for this he does not need super-maximum steering speed.
When completing the trajectory of exiting a turn, athletes move the car outward as much as possible. Formula 1 super athletes even use the curbs of the race track for this. Law-abiding drivers do not have such opportunities on public roads, but some movement of the car in a marked lane is also an element of active safety.
Driving around corners
Turns slow down the speed and make it more dangerous, but we love them. Without them, the trip would be boring and uninteresting. We would have nothing to test our driving skills on.
Driving a corner well does not mean driving fast. It is much more important to drive it in a style that even a complete layman cannot miss. If the style is characterized by the smoothness that we strive for from the very beginning, the passenger will praise you in his heart. If all the passenger’s thoughts are aimed at staying in the seat, he will not be surprised by either the high speed or the sobbing of the tires.
All turns are different. You must be able to determine their curvature, the road surface, which usually has potholes on turns, the slope of the road, and most importantly, be able to determine the speed allowed on a given turn. Perhaps 40 km/h will be the most acceptable speed, but at 45 km/h you may have to overcome significant inertia of the car.
When turning, you should first of all adhere to the basic rule of movement - drive only on your side of the roadway! Otherwise your life will be short-lived. I think that any of you, before you even started to be interested in driving a car, have already heard about “cutting the corner” on a turn. And many cannot wait to master the technique of “cutting corners” and demonstrate the highest class of their driving skills. Determined to put this into practice, they head to sports competitions where drivers actually corner like that. But there is a “small” difference: during the races the road is closed, and the driver knows for sure that no one will come towards him. If you cut corners on an ordinary, unsealed highway, at a poorly visible turn, you are entering, figuratively speaking, on a slippery slope. If you learn to cut corners that are visible, the danger will certainly be less, but the force of habit can make you experience unpleasant moments on poorly visible corners.
The main requirement - to stick to the right side - must also be subordinated to the way of driving. It is completely different from the way a racer would drive around a corner. For you, in fact, the highway narrows in half, and you must always be ready to lend part of it to an oncoming car whose driver has forgotten about the danger. So when you read the final chapters of my book about style and cornering in high-speed racing, don't try to ride on the road like a racer does. This would adversely affect your reputation as a good driver, the condition of your car, and most importantly the statistics on the average age of drivers involved in accidents.
When you make a turn, a centrifugal force acts on the car, which the car resists by the traction of the tires on the highway surface. If the centrifugal force exceeds a certain amount at a given maximum turning speed, the tires will lose traction and skid. To avoid this, you need to determine the speed at each turn, and in advance, since at the turn itself it will be too late. You know that by braking hard and braking in general, you can also cause a skid.
So, you already know three conditions for correctly driving a turn: use exclusively the right half of the highway: determine the desired speed before the turn; In principle, do not brake when turning. Let's add one more thing, fourth - never, when driving through a turn (it goes without saying, and braking three times before a turn), do not disengage the clutch - the engine remains connected to the drive wheels. Finally, the last question: when to add gas again? We'll talk about this while we're driving.
Someone else might ask: If we use the right side of the road, will the driving style be the same when turning right and turning left? The question is quite fair. Although in principle the turning method is the same, one cannot help but notice that there is still some difference.
Look at fig. 34, which shows both turns. In both cases, pay attention to the most dangerous place along the turn, where the car is closest to the middle line of the highway, that is, to the roadway of oncoming cars. For a left turn (L), this is the highest turning point; for a right turn (R), it is actually behind the turn. This happens because, even on their half of the highway, most drivers cut the turn in such a way that the turning arc is as straight as possible. This method has its advantages (less curvature means less centrifugal force), since at a given speed, by reducing the amount of centrifugal force, you can make a corner more calmly and safely. For this reason, as shown in Fig. 34, drivers start making a left turn from the very edge of the right side of the highway. At the center of the turn, they pass through the center line and finish the turn, using the spontaneous return of control to its original position, allowing the car to again drive to the very edge of the road. To make a right turn, on the contrary, they drive from the middle line of the highway, in the center of the turn they find themselves on the right edge of the road, and after the turn at the middle line they drive straight again. If you meet a car on a poorly visible turn, then when turning left, your car will be at the center line. If necessary, you can move more to the right by centrifugal force, which in this case acts in the direction out of the turn, i.e., away from the path of the oncoming car. But you can only evade if you don’t use the maximum possible speed when turning! Otherwise, you would not make it all the way through the turn, as the car would be carried off the highway. When turning right, on the contrary, the car at its highest point passes at the very edge on the right. Danger threatens when exiting a turn: the car passes near the middle line of the highway, because the centrifugal force acts in the direction of the car traveling towards it. If you need to keep the car on the right side, centrifugal force will interfere with this, and a skid may occur.
Having studied Fig. 34, you will see that the described method of driving through a turn is essentially also “cutting a corner,” only in this case the driver is limited to his half of the highway; however, this method of riding cannot be recommended.
The conclusions arising from these considerations are decisive for safe driving. So, first of all, never drive as fast as possible around a corner; always leave yourself a certain reserve, because you don’t know if another car will come towards you. If you are driving at the maximum speed allowed by the road (see Fig. 34), you will only be able to safely navigate the turn if you follow the exact path shown in the diagram. If you are forced to veer slightly to the right at the highest point of a left turn, the car will spin out of the turn. If, while completing a right turn, you are forced to do the same, the car will skid at a critical point near the highway center line, and you will endanger the car coming towards you. The same thing will happen if you incorrectly determine the permissible speed and make a turn at high speed. Therefore, you can use this method (one of the most dangerous) only on clearly visible turns, when there is absolute confidence that no one is coming towards you. It goes without saying that you turn on your own half of the road and at a moderate speed for the circumstances.
During normal driving and on blind turns, you can straighten the turning arc of the car, but in a much safer way (Fig. 35), which you must master and apply. Please note how in this case you need to start turning right or left - always from the middle line. Here you have great advantages: before turning, when you see that no one is coming towards you, you are in the middle of the road. Subsequently, when the risk of a collision with oncoming traffic increases, move further and further away from the middle of the highway and at the same time straighten the turning arc of the car and reduce the effect of centrifugal force. When turning left, you can use a larger arc if you drive along the right edge of the road, but there is always a high risk of skidding on a contaminated surface. In addition, eliminating the skid would lead to the fact that it would be necessary to part with the highway. When turning right, note that this time you do not pass through the highest point of the turn (marked with a cross) and you will reach the right edge of the road again after the bend.
The described method is also successfully applicable when turns follow one after another in different directions (Fig. 36).
You will pass such a letter S, starting before a right turn, as a simple turn. In the place marked with a cross, when the turn further is already visible, if there is no oncoming car, you can use the first described method and drive close to the middle line of the second turn. If the turn is not visible or another car is driving towards you, stay on the dotted line drawn in the figure closer to the right edge of the highway. In both cases, the S-shaped turns are significantly aligned. If a double turn begins with a left turn, it is even easier to pass. At the marked point you can already clearly see the turn and therefore drive out beyond the highest point of the second turn so that you simultaneously move away from the dangerous center line and align the car's line of movement. As you can see, the same rule applies when turning as on a flat road - look at the road not only in front of the car. You scan the road as far ahead as possible, not only in order to notice oncoming traffic in time, but also in order to correctly determine the curvature of the turn and drive the car along the most advantageous line.
You told yourself that while you are driving around the corner, you will not brake or disengage the clutch in order to eliminate the possibility of skidding and increase the stability of the car. For the same reasons, you will not change gears when turning. Shifting would mean not only having to hold the steering wheel with one hand, but also changing the connection of the engine with the drive wheels, which may be accompanied by a jerk due to poorly defined engine speeds. If the turn is so sharp that you need a lower gear at the end, shift to it before the turn: in this case, you can benefit from the engine's braking capabilities, especially when descending a mountain or on slippery surfaces. Now what about gas?
You've probably heard that there is a difference between front-wheel and rear-wheel drive cars. On a car with front drive wheels, it is more profitable to drive the entire turn with increased gas, i.e., with a load on the engine. This is possible if you correctly determine the speed before the turn, so that high speed does not become a hindrance. Naturally, you apply the gas very smoothly, especially when low gear is engaged, so that due to the rapid increase in gas the wheels do not skid and a skid occurs.
On a car with rear driving wheels, it is better to increase the gas at the moment of passing the highest point of the turn, doing this also smoothly so that the driving wheels do not slip.
Always stop braking in this way before turning, while the car is still driving in a straight line; Drive to the highest point of the turn almost without gas (with the clutch and gear engaged, of course) and then gradually increase the gas to exit the turn, picking up speed.
When making a long turn, begin to apply the gas a little earlier if you are driving at a very low speed, perhaps even at the moment when you are just starting to turn the front wheels, that is, you have already stopped braking (if you were braking at all). I have already said that we strive to drive smoothly, and a good driver will be able to calculate the speed and reduce the gas, especially not on a very sharp turn or on several turns in succession, so that it falls in time and without using the brakes.
On highways, especially in the mountains, there are often turns so sharp that they practically change direction by 180°. These are serpentines, the passage of which is very different from the passage of the turns considered. Sometimes they are so steep that if you use the way in which ordinary turns are negotiated, you can find yourself on the left half of the road, that is, on the one where traffic goes in the opposite direction. A full turn of the steering wheel is often not enough to round a serpentine road without going to the left side, especially when turning right, on the inside, along the smallest radius. Whether you're going uphill or downhill, the way you drive along the serpentine road is almost the same. First of all, learn how to ride uphill correctly.
Since, when you are about to turn, you are driving very slowly along the serpentine, you can drive to the middle line if the serpentine is steep and visible. On a very narrow road, sometimes you have to drive onto the left half of the road. This is acceptable because you will immediately turn the steering wheel to the limit, quickly return to your side of the road and - most importantly - stay on it (Fig. 37 a). If in this case you had not entered the left half of the road, the car would have ended up on it after the turn (Fig. 37 b), which is very dangerous, especially if the serpentine is not visible. But naturally, even when driving along a serpentine road, you must stop braking and shift to a lower gear (this time without fail) before entering the turn. Add gas immediately as soon as you turn the wheels all the way (the place marked with a cross), because the increased resistance when turning the steering wheel to the limit, the rise and braking effect of the engine in low gear at a very low speed will lead to the car stopping.
Before driving onto the serpentine road, try to determine whether there is a car coming towards you. You must not forget that if in such a situation you were in the path of an oncoming car, you would make its driver worry - after all, he is driving down a mountain and has probably been using all the capabilities of his brakes for a long time, the effectiveness of which may therefore be reduced. be significantly reduced. In addition, since he is driving on the outside of the serpentine road, he is on the edge of a cliff. If you see or hear another car, try to avoid meeting it directly at the turn. If you did not turn the steering wheel enough in this case (or if you were driving in the manner indicated in Fig. 37 b), you would have to stop right at the turn.
When you drive on a serpentine road to the left, the situation is simpler because by driving along the edge of the right side of the road, you reach the maximum radius of the arc, and you have “no reason to cross the path of oncoming traffic.
When going down the mountain, when turning right on a serpentine road, as already mentioned, it is more advantageous to drive onto the left side just before the start of the turn, so that when leaving it, you can keep the car on your side of the road. And this time you end up braking and shifting before you even start the turn. A lower gear makes braking easier and helps you control the car better when cornering. You, of course, do not apply gas, and the car accelerates on its own (in low gear, of course, less). You drive even more carefully down the serpentine road, because with the slightest inaccuracy you can fall off the slope. Having passed the serpentine road, add gas at the moment when you are already entering the straight line (of course, only if adding gas is necessary). If the incline is very steep, leave it in low gear, especially if there is another switchback after a short interval. Otherwise, change the gear again and slow down the car so that before the next serpentine you do not have to fully use the brakes to stop the accelerating car. In practice, of course, you encounter other types of turns, many of which are quite unpleasant. These are mainly sharp turns, especially left turns; their awkward slope is exacerbated by the natural camber of the road. This turn requires moderate speed. If it is visible, you need to drive it as close to the middle of the road as possible. A very unpleasant and dangerous turn is called a “spiral” in the language of drivers. The radius of such a turn decreases all the time, and the curvature increases. Overcoming it seems easy and innocent, but woe to the one who goes down the spiral quickly! At the moment when it seems to him that he is at the highest point of the turn, he is, in fact, at the beginning of the next turn, even steeper. This is generally one of the most unpleasant sensations while driving, and only a really dexterous driver will be able to get out of such a situation with honor, and then only if there is no oncoming car.
Long turns of the same curvature, in which the car has to be driven exactly on its own side, without seeing the end, are also unpleasant. In this case, you should especially take care to notice in time the moment when the turn ends.
I have already said that depending on the style in which the driver takes the turn, his qualifications are determined. And honestly, it’s worth mastering this art. If you were to drive for several hours on a boring freeway, with endlessly long, flat sections, with turns so large in radius that you hardly notice them, you would understand why good drivers love turns so much.
A less pleasant obstacle that you should pay extreme attention to are intersections.
