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.
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 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 krn/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; the condition
of your brakes; the weight of the
vehicle and the amount of brake force applied.
Remember: Anti-lock doesn’t change the time you neea
to get your foot up to the brake pedal or always decrease
stopping distance.
If you get too close to the vehicle in
front of you, you won’t have time to apply your brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you have
anti-lock brakes.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
firmly and let anti-lock work for you. You may feel a
slight brake pedal pulsation
or notice some noise, but
this is normal.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned
on
the news happen on curves. Here’s why:
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.
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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 vehicle 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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Off-Road Recovery
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An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel at
the recommended
9 and 3 o'clock positions, you can
turn it a full 180 degrees very quickly without removing
either hand.
But you have to act fast, steer quickly, and
just as quickly straighten the wheel once you have
avoided the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving at
all times and wear safety belts properly. You may find that your right wheels have dropped
off the
edge
of a road onto the shoulder while you're driving.
I OFF-ROAD RECOVERY /
w-/ T/ edge of paved surface
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease
off the
accelerator and then,
if there is nothing in the way, steer so
that your vehicle straddles the edge of the pavement. You
can
turn the steering wheel up to one-quarter turn until the
right fiont
tire contacts the pavement edge. Then tum your
steering wheel to go straight down the roadway.
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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 trylng 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 vehicle’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.
A cornering skid is 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.
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Of course, traction is reduced when water, snow, ice, Driving at Night
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.
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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Your anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road. Even
though you have the anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock” in the Index.
Allow greater following distance on any
slippery road.
Watch for slippery spots. The road might be fine
until you hit a spot that’s covered with ice. On an
otherwise clear road, ice patches may appear in
shaded areas where the sun can’t reach: around
clumps of trees, behind buildings or under bridges.
Sometimes the surface of a curve or an overpass may
remain icy when the surrounding roads are clear. If
you see a patch
of ice ahead of you, brake before you
are on
it. Try not to brake while you’re actually on
the ice, and avoid sudden steering maneuvers.
If You’re Caught in a Blizzal
If you are stopped by heavy snow, you could be in a
serious situation. You should probably stay with your
vehicle unless you know for sure that you are near help
and you can hike through the snow. Here are some
things
to do to summon help and keep yourself and your
passengers safe:
Turn on your hazard flashers.
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-Run
your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for
a while.
' Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
' out of the vehicle and do some fairly vigorous exercises
.. every half hour or so until help comes.
Recreational Vehicle Towing
You can tow your vehicle behind another vehicle for use
at your'destination. Be sure to use the proper towing
equipment designed for recreational towing. Follow the
instructions for the towing equipment.
Towing Your Vehicle from the Front
There are two ways to tow your vehicle from the front.
To tow your vehicle with a dolly, follow these steps:
1. Put the front wheels on a dolly.
2. Put the vehicle in PARK (P).
3. Set the parking brake and then remove the key.
4. Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing.
5. Release the parking brake.