1 Module Five Navigating Roadways. Module Five – Part 2 Navigating Roadways Topic 1Intersections...

Post on 12-Jan-2016

220 views 2 download

Tags:

transcript

1

Module FiveNavigating Roadways

Virginia Department of Education

Module Five – Part 2Navigating Roadways

Topic 1 Intersections Pages 31-32

Topic 2 Curves – Page 33

Topic 3 Hills and Mountains

Passing and Lane Changes – Teacher handout

2

Virginia Department of Education

Module 5 – Topic 1

What do you see at this intersection?

3

Drivers fail to search and identify a safe path of travel when approaching an intersection

Drivers don’t identify or understand the risks

Drivers fail to develop good driving habits to effectively manage the risks

One out of three fatal crashes occurs at intersections due to:

4

Intersections and Risks

Intersection Warning Signs

Crossroad – Four-way intersection

T Intersection - one road ends where the other road crosses

Y Intersection – you must bear either right or left ahead

5

Intersection Warning Signs

6

Roundabout – a circular intersection in which entering traffic must yield right of way

Railroad Crossing – road intersects with a railroad crossing

Traffic Flow at Intersections

7

Two-way road crossing two-way road

One-way road crossing one-way road

One-way road crossing two-way road

One-way road merges with multi-lane road

Approaching an Intersection

If possible, begin searching 20-30 seconds ahead of the intersection

Using an orderly visual search pattern

Identify the type of intersection

Identify open, closed and changing zones

Identify the best lane and lane position

Determine if the intersection is controlled or uncontrolled

8

Controlled Intersections

Intersection flow is regulated by STOP signs, YIELD signs or traffic SIGNALS

9

Intersections Without Traffic Controls Uncontrolled Intersections

The first vehicle that arrives at the intersection may proceed first if the other yields right of way

If two vehicles arrive at the same time, the driver on the left must yield to the driver on the right

There are No Signs or Traffic Lights Traffic Light is Malfunctioning

10

Applying SEEiT at Intersections

11

When you can see the intersection, begin SEARCHING for the

Type of intersectionIntersection controlsRisks or problems in your intended path of travel

Also monitor the areas to the rear

Applying SEEiT at Intersections

12

During your Search you identified potential risks, and you must now Evaluate your options on how to handle:

Traffic ControlsStop sign, yield sign, traffic lightNo traffic controls

Open, closed or changing path of travelCross traffic

Applying SEEiT at Intersections

13

You have Searched, and Evaluated and determined the best course of action. You must now EXECUTE in Time

Position vehicle in proper lane

Obey traffic controls and prepare to yield if necessary

Search and monitor space as you carefully proceed through the intersection

Time/Gap/Space

Time Needed to Execute

14

If proceeding straight across a 30-feet wide, 2-lane roadway from a stop you need a 4-second gap

If turning right and blending into the traffic flow you need a 6-second gap

If turning left and blending into the flow of traffic, you need an 8- second gap

Time/Gap/Space

15

Vehicles traveling 30 mph, are traveling at approximately 45 feet per second

To safely cross the intersection, theVehicles from the right must be at least 270 feet away

To safely turn right and blend into traffic, the

Vehicles approaching from the left must be 360 feet away

To safely turn left and blend into traffic, the

Vehicles approaching from the right must be 495 feet away

Approaching IntersectionsSafest, Most Efficient Lane Selection

Select the best lane at least a block aheadCenter lane(s) – safest when traveling straight through

Right lane is used when turning right - cross traffic, turning right on red will enter this laneLeft lane is used to turn left - yield to oncoming traffic

16

Search for Vehicles Entering Your Path of Travel

17

Vehicles turning right on red

Permitted throughout the United States unless you see these signs

Why? Right turn on red law saves gas!

The law requires drivers to STOP, (wheels motionless) before making the right on red- not a “rolling” stop!

Search for Vehicles/Pedestrians Crossing Your Path of Travel

Look for clues:

18

Driver is looking to the left or rightVehicle positioned on the left side of the laneFront wheels are turning left or rightPedestrian standing at curb

Right Turn – Risks

Right-of-way rules not followed

Failure to signal

Failure to search intersections

Failure to stop on red before turning right

Turning too wide and crossing into adjacent lane

19

Shared Left Turn Lane

20

Shared lanes help keep traffic moving by giving drivers turning left a designated shared lane in the center of the roadway

Shared Left Turn Lane

Use shared lanes to start and complete left turns

21

Shared Left Turn Lane

Crossing traffic entering a shared lane from a driveway

Is the black truck allowed to stop in the shared lane and wait for traffic

to the right to clear?

22

Move all the way into the lane to avoid blocking through traffic lane

Stop in the shared lane and wait to merge safely with traffic

Shared Left Turn Lane

Collisions do occur in shared lanes!

23

Look for other drivers using the shared laneYou can only travel 150 feet in a shared lane

Roundabouts

24

A circular intersection controlled by yield signs

Entries and exits into and out of the circle can be at multiple locations

By yielding at the entry, rather than stopping and waiting for a green light or stopping at a stop sign, significantly reduces delays

Advantages of Roundabouts

25

Fewer points of conflict

The data shows a

90% reduction in fatal crashes

75% reduction in injury crashes

Reduces delays and keeps traffic moving

Reduction in pollution and fuel use

26

Module FiveNavigating Roadways

Virginia Department of Education

Module 5 – Topic 2Negotiating Curves

Curvy roads present a high riskThere are many line-of-sight and/or path-of-travel restrictions (trees, hills, etc.)

Negotiating Curves

Blind CurveOnly a portion of the corner is visible; the rest is hidden

Negotiating Curves

S-CurveA curve in one direction with a second curve in the opposite direction

S Curve

Negotiating Curves

Crowned RoadwaysMost roadways are higher in the middle and slope to the outside for better drainageIf a road curves to the left on a crowned roadway, what happens to the weight of the vehicle?

Negotiating Curves

Banked CurveThe outside of the curve is higher than the insideHow does a banked curve help vehicles stay on the road when navigating the curve?

Banked Curve

Negotiating Curves

Uphill: acceleration is needed to maintain speedDownhill: vehicles will naturally pick up speed

Why do vehicles “slow down” going uphill and “speed up” coming downhill?

Warning Signs

Sharp Curve

Curve to right followed by curve to left

Winding Road

Road curves right – vehicle’s weight shifts left

Maximum SAFE speed is 25 mph

Basic Parts of a Curve

Entrance

Apex Approximately the middle of the curve

Exit

Forces at Work in CurvesFriction

The resistance to motion between materials moving over one another

Traction

Friction between tires and the road surface

Keeps vehicle on the road and allows vehicle to respond to acceleration, braking and steering

Traction is reduced by

speed

centrifugal force

road conditions

worn tires

Vehicle weight shifts

When traction is lost, the vehicle does not respond to driver input

Forces at Work in Curves

InertiaAn object moving in a straight line will continue in a straight line unless another force acts on itInertia must be overcome to round the curve

Traction is needed to overcome inertia If a vehicle loses traction in a curve, the vehicle will

continue straight

Forces at Work in Curves (cont.)

Inertia and traction are affected by Road surface, condition of tires, speed, sharpness of curveInertia increases with increased speed and sharpness of the curveTraction decreases with increased speed, reduction in tire’s contact with road surface and road surface conditions

Forces at Work in Curves

Vehicle Weight TransferThe weight of a vehicle rounding a curve shifts to the opposite direction of the curve

Rounding a curve to the right will result in the vehicle’s weight transferring left The right tires may lose contact with the road resulting in less traction

Photo courtesy of AAA Foundation

Forces at Work in Curves

Rounding a curve with too much speed can result in the vehicle turning over

Adding weight to the top of a vehicle also increases the tendency to turn over as the center of gravity has been raised

Speed control and smooth, controlled steering are needed to maintain control

Negotiating CurvesVehicle performance in a curve depends upon

Weight of the vehicleCenter of gravity of the vehicle SpeedPavement conditionsTire conditionDriver input

What is the best method of steering through this curve?Why?

Applying SEEit in Curves

Search the road ahead• Uphill/downhill?• Blind curve?• Crowned or banked?• Sharpness of curve?• Road surface conditions?

What can you determine as you search the curve ahead?

Applying SEEit in Curves

After SearchingEvaluate your options

Lane positionVisibilitySpace management

Speed controlControlled braking before apexAccelerate out of the curve

SteeringPush-Pull

Line of sightLook through the curve

Path of travel

Execute in Time

Applying SEEit in Curves

When approaching a Curve to the Left

It is generally best to approach the curve in Lane Position 3, as far away as possible from oncoming trafficThis position also provides the best targeting point for your line of sight

Diagram on workbook page 33 #1 Begin inLane Position 3

Applying SEEit in Curves

When approaching a Curve to the RIGHT

An outside road position on entry to a right curve (Lane Position 2) allows for a longer braking distance on entry and a better chance of establishing a sightline to the apex and exit of the curve

Diagram page 33 #2 Begin in Lane Position 2

Module 5 – Topic 3

Hills and Mountains

Hills/Mountains

Applying SEEiT Search ahead for advisory speed signs, oncoming traffic, road conditions for traction control, and slow moving vehiclesEvaluate if the hill has curves and determine the type of curve for decision-making about speed and lane positions

Evaluate

Driving Uphill—Speed ControlExtra power may be needed to maintain uphill speedSlower moving vehicles should travel in the right-hand lane

Photo courtesy of AAA Foundation

Evaluate

What is gravity?How does it affect a vehicle on hills or mountains?

Evaluate

Descending Hills & MountainsGravity will make the vehicle go faster

Downshift and use the transmission to reduce speed and help keep brakes from overheating and overheating

What are the clues in this scene that describe the roadway conditions?

Evaluate

DescendingHeavier vehicles will pick up more speed downhill because of gravity

Check the rear zone for vehicles that may be having trouble controlling speed

Turn off the cruise control

What should the pickup truck driver remember when passing the tanker truck?

Evaluate

Cresting the HillThe LOS at a hill crest is very limitedBe prepared for:

Stopped vehiclesSlow moving vehiclesOncoming vehicle in your lane

Be prepared adjust speed or position to avoid a hazardWhat potential hazards could exist on the other side of the hill crest?

Execute in Time

Carry Out Your DecisionAdjust speed and/or position if neededWhat would you do if an approaching vehicle crossed the center of the road?

Hills/Mountains

Runaway RampsRunaway ramps are designed for large trucks that lose braking control on steep hillsThese sections have deep gravel, sand barrels and other materials to help slow down the runaway vehiclePull off the road if you see a runaway truck behind you

Hills/Mountains

Starting on Hills—Automatic TransmissionSome steep hills require using the accelerator and brake together to keep the vehicle from rolling backwardMaintain brake pressure until ready to moveUse the right foot to accelerate and simultaneously slowly release the brake

Passing and Lane Changes

Refer to notes handout

How do you make a Lane Change?**Use SMOG (signal, mirrors, over shoulder, go)1. Check traffic ahead, to the sides, and behind 2. Signal3. Check your mirrors – rear view and side view4. Make a head check5. Accelerate smoothly6. Change lanes smoothly7. Cancel signal8. Adjust speed and/or vehicle position to create space all around your vehicle

Passing on Multi-Lane Roads1. Check traffic ahead, to the sides, and behind Signal2. Make a head check3. Accelerate smoothly4. Change lanes smoothly5. Cancel signal6. Pass and signal to return7. Check mirrors8. When both sets of headlights of the vehicle being passed are visible, return to the lane9. Cancel signal10. Adjust speed and/or vehicle position to create space all around your vehicle

When Being Passed

Monitor passing vehicle’s positionMove to lane position 3 to increase space cushionDo not increase speed—decelerate if necessaryOnce passed, create space ahead and behind

How much space is needed to pass another car?

REGULAR SIZED MOTOR VEHICLE

_____ FOOTBALL FIELDS

At 40 Mph – You would need 5 FOOTBALL FIELDS

How much space is needed to pass a truck?

TRACTOR TRAILER

_____ FOOTBALL FIELDS

At 40 Mph – You would need 7.5 FOOTBALL FIELDS

Passing is not permitted…

HillsRailroad crossingsSolid yellow linesCurves Intersections

Headlights are needed during the day

Headlights increase visibility of a vehicle, passing vehicles, and oncoming vehicles.