Driving Safely
Perception distance + _________________ + braking distance = total stopping distance
Reaction distance
What is one thing you are responsible for as the driver of cargo?
-Inspecting the cargo.
-Recognizing overloads and poorly balanced weight.
-Knowing your cargo is properly secured and does not obscure your view ahead to to the sides.
-Knowing your cargo does not restrict access to emergency equipment.
After coupling, how much space should be between the upper and lower fifth wheel?
None!
The air brakes are really three different braking systems: the _________________, the parking brake, and the emergency brake.
service brake
What is an example of emergency equipment?
Fire extinguishers
Spare electrical fuses
Warning devices for parked vehicles
If you drive two times as fast, your stopping distance doubles. True or False?
False! It quadruples.
Name two situations where legal maximum weights may not be safe.
If the cargo is top-heavy or if there is too much weight on the steering axle.
What is off-tracking?
When a vehicle goes around a corner, the rear wheels follow a different path than the front wheels.
What are spring brakes?
Spring brakes are emergency mechanical brakes that come on when the air pressure drops to 20-45 psi.
You should use low beams whenever you can. True or False?
False! You should use high beams whenever you can.
If you stop on a one-way or divided highway, where should your three warning devices go?
10 feet, 100 feet, and 200 feet toward approaching traffic.
What does GVWR stand for?
Gross Vehicle Weight Rating
True or false: You brake the same way with air brake systems as you normally brake.
True.
Why do you have to drain the air tanks at the end of each day of driving?
Compressed air usually has some water and some compressor oil in it, which is bad for the air brake system.
How far ahead should you look (in seconds?)
12 to 15 seconds.
The sum of the weights of your power unit and the towed unit is equal to what?
The Gross Combination Weight Rating.
What two things are important strategies for preventing rollover?
-Keep the cargo as close to the ground as possible.
-Drive slowly around turns.
All vehicles with air brakes must have a low air pressure warning signal. When does it come on?
When the pressure drops below 60 psi.
What are two things to consider when selecting and maintaining a certain speed?
-Total weight of the vehicle and cargo
-Length of the grade
-Steepness of the grade
-Road conditions
-Weather
How much space should you have in front of you while driving?
1 second per ten feet of vehicle + 1 extra second if traveling over 40 mph.
What is the minimum # of tie-downs for any flatbed load?
2, or one per 10 feet of cargo.
What is a service air-line for? (Also called control line or signal line).
It is controlled by the foot brake or the trailer hand brake and is connected to relay valves, which allows the trailer brakes to be applied more quickly than is otherwise possible.
When inspecting your dual brake air system, what should the pressure buildup be within 45 seconds?
It should build from 85 to 100 psi.
What is a safety valve? What does it mean if your safety valve is releasing air?
A safety relief valve protects the first tank the air compressor pumps air into, and the rest of the system, from too much pressure. If your safety valve is releasing air, something is wrong and you need to go to a mechanic.
What two things should be in place before you can safely inspect the engine compartment?
Parking brakes on, wheels chocked.
How often must you stop while on the road to check your cargo?
-within the first 50 miles
-every 3 hours OR 150 miles
-after every break you take while driving
Around what part of the kingpin should you see the fifth wheel jaws closed when inspecting your coupling?
The shank
What is the maximum safe leakage rate in a single vehicle and in a combination vehicle?
What is the emergency air-line for? (Describe two purposes)
1. Supplies air to the trailer air tanks.
2. Controls the emergency brakes on combination vehicles.