ROADWAY VARIATIONS

LESSON #6

Section 1 - HILLS
    Hills require adjustments in your driving because of shortened sight distance near the crest of the hill, tendency for the vehicle to speed up and an increased stopping distance when going downhill, and a tendency for the vehicle to slow down when going up a hill.

    Because of shortened sight distance at the crest of a hill, be certain to be well to the right in your lane and be ready to react quickly should something appear in your lane.  Slow down if you are in an area where it could be likely that animals or farm vehicles or other obstacles could be on the road.

    Always have a vehicle in gear when going down a hill.  As soon as you go over the crest of the hill, watch and keep your speed from going over the speed limit by letting up on the gas and braking if necessary.  Continuous partial brake pressure is best if braking is needed for controlling speed downhill.  Do not brake hard and then let up intermittently.  Observe other vehicles, especially trucks, because the extra weight tends to make them increase speed even more.  Observe hill signs for indication of steep downhill grades.

    Just before starting up a hill increase accelerator pressure and continue to do so in order to maintain speed.  Be alert for vehicles, especially smaller cars, trailers, or trucks which are not always able to maintain speed up the hills and be ready to adjust speed accordingly.  DO NOT PASS if you are too close to the crest of the hill.
    Procedures
    a.    Observe and obey hill signs.
    b.    At the crest of the hill, stay right and be ready to keep the car from speeding up.
    c.    When going downhill maintain speed control with accelerator up and/or continuous brake pressure.  If the downhill is very steep, shift to a lower gear to obtain braking effect (compression) from the engine.
    d.    When going uphill, increase accelerator pressure and watch for slower vehicles.

Section 2 - CURVES
    Speed may need to be reduced when taking a curve due to shortened sight distance and centrifugal force.

    Therefore, when entering a curve, focus on the farthest clear path of travel possible.  Look through the curve.  Be prepared to react quickly should something appear in your lane.  Slow down if you are in an area where it could be likely that animals or farm vehicles or other obstacles could be on the road.

    Centrifugal force is the result of the principle of inertia.  This means that when rounding a curve the car tends to go straight, toward the outside of the curve.   If the curve is sharp enough or you enter too fast, it could cause the car to skid toward the outside of the curve and the driver could lose control of the car.  At this time, should a driver brake hard enough to lock the wheels it would probably cause the vehicle to skid off the road.

    Chances of a vehicle skidding are minimized when a driver slows before entering a curve, maintains a constant speed through the first half of the curve and then slightly accelerates through the rest of the curve.
    Procedures
    a.    Look for curve signs.
    b.    Look well ahead to anticipate steering corrections.
    c.    Reduce speed, if necessary, for sight distance or sharp curve.
    d.    Accelerate slightly coming out of the curve if it was necessary to slow down because of a sharp curve.
    e.    If you begin to skid, use steering mostly to make corrections - DO NOT BRAKE HARD.

Section 3 - GRAVEL SURFACES
    Gravel surfaces require driving adjustments chiefly because of less traction.
    Procedures
    a.    Drive considerable slower than on a paved roadway.
    b.    Avoid any sharp turning movements.
    c.    Increase following distance substantially.

    Stopping distances will be longer.  Brakes will need to be applied more lightly and gradually than on pavement to keep the wheels from locking up.

    More steering adjustments will be needed but also they will need to be done more lightly and gradually than on pavement.

    Speed should be reduced before going onto gravel surface roadways from paved surfaces.

    For the most part you should attempt to travel in the tracks left by other vehicles.

    Care should be taken when crossing the loose gravel buildup between tire tracks.  Extreme care must be taken when having to travel on the gravel buildup when meeting an oncoming car.  UNDER NO CIRCUMSTANCES should you pass a vehicle moving at a reasonable speed, even if less than what you desire to travel.

    Flying bits of gravel can break headlights and windows.  There is usually a substantial amount of dust when the roads get dry in the summertime.  These are two more reasons for increasing your following distance.

Section 4 - NARROW PAVED ROADS
    The danger in narrow paved roads is that there is less room for lane control and steering errors as compared to freeways or wide shouldered two lane highways.  Therefore, constant lane position is required.

    Generally speed should be reduced.  Most of this type of roadway are county or "back-country" roads where speed limits are reduced mainly for that reason.  Higher speed increases the chance of small errors that would be no problem on a wide shouldered highway but could be on a narrow paved road.

    Extreme care should be taken if the right wheels drop off the pavement to use off road recovery procedures and NOT to steer back onto the pavement immediately.

Section 5 - BRIDGES
    The potential dangers in crossing bridges is caused by the fact that many are narrower than the roadway including shoulders, and that bridges tend to frost over first and sometimes even when no other part of the roadway is frosted.

    Because they are narrower, often to the point that you can't get out of the travel lane if you stop, you should not stop or park your vehicle on bridges except in extreme emergency.  Even if you should have a blowout on a narrow bridge, you should drive slowly off the bridge until you can get your car completely onto the shoulder out of the travel lane.

    Also because of the narrowness and barricades to each side, you usually do not have an out.  For that reason, you should make extra effort to separate risks by not being on the bridge while meeting other traffic, especially large trucks.

    Sometimes this is not possible or it may cause more conflict by slowing or simply not having space to separate.  At that time it is especially important to maintain lane position more efficiently (usually centered in the lane) which is usually required on narrow bridges even when no oncoming traffic is immediately present.

Section 6 - RAILROAD CROSSINGS
    Observe signs and comply with controls for railroad crossings.

    Look both ways before crossing any track.  Stop if a train is coming (15 to 20 feet from the track or behind the marked stop line).  If the train is very long at all, it is wise to put on the parking brake and shift to park (neutral in a standard shift car).

    Don't ever park or stop and wait while on railroad tracks.

    After waiting for a train to pass proceed across railroad tracks only after you are sure it is clear in both directions, especially if there are multiple tracks where a train from the opposite direction could be hidden by the first train.

    You should slow down before crossing tracks and roll across because the crossing can often be very rough.

    Don't trust that if there are warning controls and they are off, that you can proceed without looking - controls can malfunction.

    The great majority of railroad crossings have only signs, not controls.

    Remember that busses and tank trucks are required to stop at all railroad crossings - so be prepared to stop behind them if they must stop in the travel lane or proceed around them with extreme caution if there is an extra lane provided for them to stop.

Section 7 - TUNNELS
    The potential dangers from approaching and traveling through the majority of tunnels is caused by reduced visibility during the day and space restriction of a narrow roadway without shoulders.

    When entering a tunnel during daytime, especially if it is sunny, visibility is immediately affected by the contrasting darker interior of the tunnel, even when well lighted.  Therefore, it is important that before entering a tunnel you:
    a.    Remove sunglasses if they are being worn.
    b.    Turn on headlights whether required by signing or not.  (This is not for you to be able to see better, but is to make you more visible to other vehicles in the tunnel.)
    c.    Firmly establish your lane position in the center of the proper lane of travel.
    d.    Observe and comply with posted regulatory or warning signs.

    After entering the tunnel, you should:
    a.    Observe side structures or walls and pavement markings to be sure you are maintaining the best lane position to allow space for yourself and other vehicles in the tunnel.
    b.    Do not stop or park in a tunnel except in extreme emergency.  (A flat tire is not an extreme emergency.)  If you must stop, turn off your engine to help reduce carbon monoxide buildup in the tunnel.

    When you leave the tunnel you should:
    a.    Be prepared for momentary "blinding" of the daylight (especially if it is a long tunnel and/or it is a bright sunny day).  Be extra conscious of the pavement markings and your lane position until your eyes adjust (which is usually rather quick for most people) or you can put your sunglasses on.
    b.    Turn off your headlights (unless, of course, it is your practice to drive with headlights on at all times for safety - this is best.)

    Some tunnels are very short.  For these it may not be necessary to take the step of turning on your headlights, but still should command some special attention to the potential danger of narrower roadway and momentary slight vision reduction.

Section 8 - CHUCKHOLES (Surface Irregularities)
    If possible, steer to avoid chuckholes.
    Procedures:
    a.    Observe chuckhole.
    b.    Reduce speed.
    c.    If possible, steer to avoid chuckhole.
    d.    If chuckhole is unavoidable, brake, then release brake before wheels encounter the chuckhole (roll through the chuckhole).

    This procedure aids the suspension of the vehicle.  Grasp the steering wheel firmly as you drive through a chuckhole.

    If you hit a chuckhole with the brakes on, there is a greater shock for both the car and people in it.  This is because the wheels are not able to roll through and over the chuckhole as easily.  That is why you should apply brakes before hitting a chuckhole and then release them as you get to the chuckhole.