Control Of A Vehicle; Braking - GMC 1994 Safari Owner's Manual

Control of a Vehicle
You
have three systems that make your vehicle go where you want it to go.
They are the brakes, the steering and the accelerator. All three systems have
to
do their work at the places where the tires meet the road.
Sometimes, as when you're driving on snow or ice, it's easy to ask more of
those control systems than the tires and road can provide. That means you
can lose control of your vehicle.
Braking
Braking action involves perception time and reaction time.
First, you have to decide to push on the brake pedal. That's perception time.
Then you have to bring up your foot and do it. That's reaction time.
Average reaction time is about 314 of a second. But that's only an average. It
might be less with one driver and as long as two or three seconds or more
with another. Age, physical condition, alertness, coordination, and eyesight
all play a part. So do alcohol, drugs and frustration. But even in 314 of a
second, a vehicle moving at 60 mph (100 kmh) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so keeping enough space
between your vehicle and others is important.
And, of course, actual stopping distances vary greatly with the surface
of
the
road (whether it's pavement or gravel); the condition of the road (wet, dry,
icy); tire tread; and the condition of your brakes.
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