Control of a Vehicle Braking
YOU have three systems that make,your vehicle go where Braking action involves perception time and
you want it to go. They
are the brakes, the steering and reaction time.
the accelerator, All three systems have to do their work
at the places where the tires meet
the road. 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 3/4 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
3/4 of a second, a vehicle
moving at
60 mph (100 km/h) 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.
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.
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Experienced driver or beginner, each of us is subject to
the same laws of physics when driving
on curves. The
traction of
the tires against the road surface makes it
possible for the vehicle to change its path when you turn
the front wheels.
If there’s no traction, inertia will keep
the vehicle going in the same direction. If you’ve ever
tried
to steer a vehicle on wet ice, you’ll understand this.
The traction
you can get in a curve depends on the
condition of your tires and the road surface, the angle at which the curve is banked, and your speed. While you’re
in a curve, speed is the one factor you can control.
Suppose you’re steering through a sharp curve. Then you
suddenly accelerate. Both control systems
-- steering
and acceleration
-- have to do their work where the tires
meet the road. Adding the sudden acceleration can demand
too much of those places. You can lose control.
What should
you do if this ever happens? Ease up on the
accelerator pedal, steer the vehicle the way
you want it
to go, and slow down.
Speed limit signs near curves warn that you should
adjust your speed. Of course, the posted speeds are
based on good weather and road conditions. Under less
favorable conditions you’ll want to go slower. If
you need to reduce your speed as you approach a
curve, do it before you enter the curve, while your front
wheels are straight ahead.
Try to adjust your speed
so you can “drive” through
the curve. Maintain a reasonable, steady speed. Wait
to accelerate until
you are out of the curve, and then
accelerate gently into the straightaway.
’Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and find
a
truck stopped in your lane, or a car suddenly pulls out
from nowhere, or a child darts out from between parked
cars and stops right in front of you. You can avoid these
problems by braking
-- if you can stop in time. But
sometimes you can’t; there isn’t room. That’s the time
for evasive action
-- steering around the problem.
Your Buick can perform very well in emergencies like
these. First apply your brakes. (See “Braking in
Emergencies” earlier in this section.) It is better to
remove as much speed as you can from
a possible
collision.
Then steer around the problem, to the left
or right depending on the space available.
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Check your mirrors, glance over your shoulder, and start your left lane change signal before moving
out
of the right lane to pass. When you are far enough
ahead of the passed vehicle to see its front
in your
inside mirror, activate your right lane change signal
and move back into the right lane. (Remember that
your right outside mirror is convex. The vehicle you
just passed may seem to be farther away from you
than it really is.)
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the
next vehicle.
Don’t overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not flashing, it
may
be slowing down or starting to turn.
If you’re being passed, make it easy for the
following driver to get ahead
of you. Perhaps you
can ease a little to the right.
Loss of Control
Let’s review what driving experts say about what
happens when the three control systems (brakes, steering
and acceleration) don’t have enough friction where the
tires meet the road to do what
the driver has asked.
In any emergency, don’t give up. Keep trying to steer and
constantly seek an escape route or area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not “overdriving”
those conditions. But skids are always possible.
The three types of skids correspond to your Buick’s
three control systems. In the braking skid, your wheels
aren’t rolling. In the steering or cornering skid, too
much speed or steering in
a curve causes tires to slip and
lose cornering force. And
in the acceleration skid, too
much throttle causes the driving wheels to spin.
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A cornering skid and an acceleration skid are best
handled by easing your foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot
off the
accelerator pedal and quickly steer the way you want the
vehicle to go.
If you start steering quickly enough, your
vehicle may straighten out. Always be ready for a
second skid if it occurs.
Of course, traction
is reduced when water, snow, ice,
gravel or other material is on the road.
For safety, you’ll
want to slow down and adjust your driving to these
conditions.
It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on
a surface with reduced traction, try
your best to avoid sudden steering, acceleration or
braking (including engine braking
by shifting to a lower
gear). Any sudden changes could cause the tires
to slide.
You may not realize the surface is slippery until your
vehicle is skidding. Learn to recognize warning
clues
-- such as enough water, ice or packed snow on
the road to make
a “mirrored surface” -- and slow down
when you have any doubt.
Remember: Any anti-lock brake system
(ABS) helps
avoid only
the braking skid.
DrivinP at Night
Night driving is more dangerous than day driving.
One reason
is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems, or by fatigue.
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Driving in Rain and on Wet Road9 Rain and wet roads can mean driving trouble. On a wet
road,
you can’t stop, accelerate or turn as well because
your tire-to-road traction isn’t
as good as on dry roads.
And, if your tires don’t have much tread
left, you’ll get
even less traction. It’s always wise to go slower and be
cautious if rain starts to fall while you are driving. The
surface may get wet suddenly when your reflexes are
tuned for driving on dry pavement.
The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy rain
can make
it harder to see road signs and traffic signals,
pavement markings, the edge
of the road and even
people walking.
It’s wise
to keep your wiping equipment in good shape
and keep your windshield washer tank filled. Replace
your windshield wiper inserts when they show signs of
streaking or missing areas on
the windshield, or when
strips of rubber start
to separate from the inserts.
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Driving too fast through large water puddles or even
going through some car washes can
cause problems, too.
The water may affect your brakes. Try
to avoid puddles.
But
if you can’t, try to slow down before you hit them.
Wet brakes can cause accidents. They won’t work
well in
a quick stop and may cause pulling to one
side. You could lose control
of the vehicle.
After driving through a large puddle
of water or
a car
wash, apply your brake pedal lightly until
your brakes work normally.
Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the water.
This can happen if the road is wet enough and you’re
going fast enough. When your vehicle
is hydroplaning,
it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can
if your
tires haven’t much tread or if the pressure in one or
more is low.
It can happen if a lot of water is standing on
the road. If you can see reflections from trees, telephone
poles or other vehicles, and raindrops “dimple” the
water’s surface, there could be hydroplaning.
Hydroplaning usually happens at higher speeds. There
just isn’t
a hard and fast rule about hydroplaning. The
best advice is to slow down when
it is raining.
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NOTICE:
If you drive too quickly through deep puddles or
standing water, water can come
in through your
engine’s air intake and badly damage your
engine. Never drive through water that is slightly
lower than the underbody
of your vehicle. If you
can’t avoid deep puddles or standing water, drive
through them very slowly.
iome Other Rainy Weather Tips
J
Turn on your low-beam headlamps -- not just
your parking lamps
-- to help make you more visible
to others.
Besides slowing down, allow some extra following
distance. And
be especially careful when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared to have your view restricted
by road spray.
Have good tires with proper tread depth. (See
“Tires”
in the Index.) One
of the biggest problems with city streets is the
amount of traffic on them. You’ll want to watch out
for
what the other drivers are doing and pay attention to
traffic signals.
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Here are some things you can check before a trip:
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Windsh.ield Washer Fluid: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked
all levels?
Lamps: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe,
trouble-free trip.
Is the tread good enough for
long-distance driving? Are
the tires all inflated to the
recommended pressure?
Weather Forecasts: What’s the weather outlook
along your route? Should you delay your trip
a short
time to avoid a major storm system?
Maps: Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as “highway hypnosis”?
Or is
it just plain falling asleep at the wheel? Call it
highway hypnosis, lack
of awareness, or whatever.
There is something about an easy stretch of road with the
same scenery, along with the hum of the tires
on the road,
the drone of the engine, and the rush of the wind against
the vehicle that can make
you sleepy. Don’t let it happen
to you!
If it does, your vehicle can leave the road in less
than
a second, and you could crash and be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
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Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan
the road ahead and to
the sides. Check your rearview mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest, service
or parking area and take a nap, get some exercise, or
both. For safety, treat drowsiness on the highway as
an emergency.
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