Emergency Maneuver vs. Cornering
Many training programs teach an exercise called Lines and Apexes. The goal of the exercise is to train the student to maximize their speed through a corner; from a vehicle dynamics viewpoint, that is a different skill set than operating a vehicle in a sudden emergency scenario.
If a driver is confronted with an emergency, the amount of turning, steering, and braking needed to get out of trouble is not predetermined; that is why it is called an emergency. When the driver is confronted with an emergency – it is “Holy Stuff,” and then the driver operates the vehicle’s control. From a vehicle dynamics perspective, an emergency maneuver is different from driving through a corner. When driving through a corner, the energy applied to the vehicle’s center of gravity is applied relatively slowly and smoothly. I know it does not seem slow from inside the vehicle, but from the vehicle dynamics point of view – it is.
There is a big difference between energy applied to the vehicle going through a corner at speed and the energy applied to a vehicle during an emergency maneuver. In an emergency, a massive spike of energy is applied to the vehicle’s center of gravity.
The driver does not purposely put a high spike of energy on the vehicle. Consider that if they are moving at the rate of 40 MPH or 65 KPH and an obstacle is in their path 75 feet or 22.5 meters away, they are 1.25 seconds away from the obstacle. Since it is a surprise, the driver’s reaction time will eat up at least half a second. At that point, the driver has to turn the steering wheel to create enough energy to move the vehicle away from the obstacle and not too much energy so that it would cause the vehicle to go out of control and do all that in a couple of tenths of a second in the blink of an eye.
The success of the event will depend on the vehicle’s speed, how quickly the steering wheel is moved, and the capability of the student/vehicle combination. Racing fans may consider the following blasphemy. However, when the center of gravity of a vehicle gets hit with a large spike of energy, it does things that would challenge the best racer. The driver will need to perform an emergency maneuver with a vehicle with about 75% less handling capability than the average race car. That is one hell of a dance. The skill needed to drive out of an emergency will not be learned by driving lines and apexes. This is a skill learned in the lane-change exercise –the dimensions of the exercise, the speed the students enter, and when the signal is given for the lane change all need to be synchronized. When it is all together and working, it is one of the most valuable skills that can be taught.
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