Words from the General Knowledge test about controlling the vehicle: stopping distance, skids, following distance, securing cargo, and the limits on speed, alcohol and fatigue.
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following distance
дистанція до попереднього автомобіля
Space you leave between your truck and the vehicle ahead.
A heavy truck needs far more room to stop than a car, so the manual measures following distance in seconds, not car lengths. The rule is one second for every 10 feet of vehicle length at speeds under 40 mph, plus one more second above 40 mph. Count from when the vehicle ahead passes a fixed mark until you reach it, and add more time on wet or icy roads.
Tested:questions give a speed and vehicle length and ask how many seconds to keep, how to check your gap, and how to handle a tailgater.
It is made of three parts: perception distance, reaction distance and braking distance; with air brakes, brake lag is added. Speed matters most: double your speed and the braking distance grows about four times. Wet roads, worn tires and an empty truck all stretch it.
Tested:which parts add up to stopping distance, how doubling speed changes it, and why empty or wet conditions lengthen it.
Distance traveled between seeing a hazard and recognizing it as one.
Your eyes can be on a hazard before your mind understands it is a hazard. Fatigue, distraction and poor visibility stretch this time, and the vehicle keeps moving the whole while.
Tested:what perception distance is, which part of total stopping distance it is, and how long it takes an alert driver.
Distance covered between recognizing a hazard and hitting the brake.
Once your brain knows there is danger, your foot still has to move from the accelerator to the brake pedal. That takes most drivers under a second, but at highway speed the truck covers a surprising distance.
Tested:what reaction distance means and which parts add up to total stopping distance.
Distance traveled from the brakes taking hold to a full stop.
This is the part of stopping distance that speed changes most: go faster and it grows much faster than your speed does. Good brakes, good tires and a dry road keep it short; a wet road or an empty, bouncing truck makes it longer.
Tested:how braking distance changes when you double or triple your speed and which parts make up total stopping distance.
Perception, reaction and braking distances added together; with air brakes, brake lag too.
It is the full distance from the moment a hazard appears to the moment the truck stands still. The manual gives one total in the driving section and a longer one for air-brake vehicles, because air takes time to reach the brakes. Both figures are correct; read the question to see which one it wants.
Tested:what makes up total stopping distance, and how far a truck travels at highway speed with and without air-brake lag.
Area around your vehicle that your mirrors cannot show you.
Trucks have big blind spots: directly behind, right beside the cab and trailer, and close in front of the hood. Check mirrors often so you know when a car has slipped into one, and use a helper when backing.
Tested:why backing needs a helper, what to do when a car you saw in the mirror disappears, and when to check mirrors.
Skids come from braking too hard, steering too sharply, giving the drive wheels too much power, or simply driving too fast for the road. Most are drive-wheel skids; the cure is to stop braking or accelerating, then steer where you want to go.
Tested:what causes skids, how to correct a drive-wheel braking skid, and why retarders or ABS matter on slippery roads.
The rear drive wheels lose traction and slide sideways.
It is the most common skid, caused by braking hard enough to lock the drive wheels or by spinning them with too much power. A straight truck spins out; a tractor-trailer can jackknife because the trailer pushes the tractor sideways. Fix it by getting off the brake or accelerator, then countersteering.
Tested:what a drive-wheel skid can do when you pull doubles and the right order of actions to correct one.
Front tires lose grip and the truck ignores the steering wheel.
Driving too fast for conditions causes most of them; worn front tires or too little weight on the front axle also help cause them. There is only one way out: stop turning or braking so hard and let the truck slow down until the front tires grip.
Tested:what a straight truck does in a front-wheel skid and what causes one.
Steering back the opposite way after a swerve or skid.
A vehicle that is turning back on course tends to keep turning. Unless you steer the other way quickly, you skid in the opposite direction; think of swerve and countersteer as one movement. It takes practice, best learned on a skid pad.
Tested:what countersteering is, the correct sequence to end a drive-wheel skid, and how to steer back after swerving with doubles.
Tires ride up on water and lose contact with the road.
It is like water skiing: with no grip you may not be able to steer or brake. It can start at speeds as low as 30 mph where water pools, and worn tread or low tire pressure make it more likely. To recover, release the accelerator and push in the clutch so the wheels turn freely; do not brake.
Tested:what hydroplaning is, which clues on the road warn it may happen, when it is most likely, and how to recover.
Thin, clear ice that makes the road look only wet.
You can see the pavement through it, so it is easy to miss. Any time the temperature is near or below freezing and the road looks wet, treat it as ice. Bridges and shaded stretches freeze first; feel the front of your mirror for ice as a check.
Tested:what black ice means and how to recognize an icy road that only looks wet.
Rain, ice, snow, loose gravel and worn tread all reduce traction, so you must slow down. The manual's rule: cut speed by about a third on a wet road and by half or more on packed snow. An empty truck has less traction because less weight sits on the tires, and retarders or hard braking can break traction on slippery roads.
Tested:how poor traction changes stopping distance, when retarders can cause a skid, and why empty trucks have less grip.
Following another vehicle too closely to stop safely if it brakes.
When a car tailgates your truck, do not speed up and do not tap your brakes or flash your lights to scare it off. Signal early, slow gradually, and open up more room ahead so the tailgater can get around you. Trucks get tailgated most when they are slow, uphill, or in bad weather.
Tested:how to deal with a tailgater, what not to do, and how following too closely relates to serious traffic violations.
Soft gravel bed or uphill lane that stops a runaway truck.
Ramps sit a few miles below the top of long mountain grades and are marked by signs. The loose material drags the wheels to a stop; some ramps also climb so gravity helps. If your brakes fail on a hill, use the ramp without hesitating; drivers who skip it often crash.
Tested:what escape ramps are made of, where they are located, and whether to use one when brakes fail.
Downhill stretch of road where gravity speeds the truck up.
Pick a safe speed before the hill, based on the truck's weight, the length and steepness of the grade, the road and the weather. Shift to a low gear at the top and let the engine hold the speed; brake in firm, short applications instead of riding the pedal. Brakes that are used too much overheat and fade.
Tested:which factors set your speed on a downgrade, when to downshift, and the right braking technique on a long, steep hill.
An uphill stretch of road, where gravity slows the truck down.
Heavy trucks lose speed climbing, so stay in the right lane and do not pass another slow vehicle unless you can get by quickly. Starting from a stop on a steep upgrade needs the parking brake or trailer hand valve so you do not roll back.
Tested:how to start a loaded bus on a steep upgrade and what to do when a heavy load slows you on a hill.
Safe speed through a curve, below what is posted for cars.
Take a curve too fast and either the tires lose grip and you slide off, or they hold and the truck rolls over. Slow down before the curve, not in it, because braking in a curve can lock the wheels. Be in a gear that lets you accelerate slightly through the turn.
Tested:how to keep doubles or a tanker upright in curves and why the posted speed may be too fast for a truck.
Moving your vehicle from one traffic lane into the next.
Signal first, then check your mirrors before moving, after signaling, as you start to move, and once you are in the new lane. Change lanes slowly and smoothly so a driver you missed has time to react. With doubles or triples, the extra length means you need a longer gap.
Tested:when to check your mirrors during a lane change, how to signal, and what to do when a vehicle you saw has vanished.
Joining moving traffic from an on-ramp or an ending lane.
A loaded truck accelerates slowly, so you need a much bigger gap than a car. Use your mirrors to be sure the gap is big enough before you enter, and expect that merging drivers may not see you.
Tested:how to merge safely, how to use mirrors when merging, and how to react to a construction vehicle merging into your lane.
Overtaking a slower road user and moving ahead of them.
Assume the person you are passing has not seen you; a light horn tap, or a headlight flick at night, warns them. Pass only where it is legal and you can see far enough ahead; a slow truck needs a long way to get by. Going uphill, do not pass a slow vehicle unless you can get around quickly.
Tested:what to assume about a road user you are passing, what not to do while passing, and how to handle motorcycles.
The right to proceed first when two road users' paths cross.
A train always has it at a crossing, and you must yield to stopped emergency vehicles by moving over or slowing down. Never assume the other driver will yield to you; many hazards come from drivers who believe they have the right-of-way.
Questions seldom use the term directly; the manual applies it to trains at crossings and to moving over for stopped emergency vehicles.
Road section where crews are working, often with narrow lanes.
Speeding is the top cause of injury and death in work zones, so hold the posted limit and watch the speedometer on long stretches. Expect uneven pavement, sharp lane shifts, workers close to traffic and construction vehicles pulling in. Use flashers or brake lights to warn drivers behind you.
Tested:how to drive safely through construction zones and how to respond when a construction vehicle merges into your lane.
Intersections are where paths conflict, so slow down and look for drivers who may not stop. Turning left, reach the center of the intersection before you turn, so the trailer does not off-track into another car. With two left-turn lanes, use the right-hand one.
Tested:how to turn left at an intersection, which of two turn lanes to use, and how to handle slippery intersections in a tanker.
Highway whose opposing lanes are separated by a median or barrier.
Traffic on your side all moves one way, so a stopped truck's warning devices go only behind it, toward approaching traffic. Space the three triangles 10, 100 and 200 feet behind the vehicle.
Tested:where to place your warning triangles when you must stop on a divided or one-way highway.
An undivided road with a single lane in each direction.
Because traffic comes from both directions, a stopped truck needs warning devices both ahead and behind, plus one near the vehicle. Put one within 10 feet of the vehicle, one 100 feet behind and one 100 feet ahead. If a hill or curve hides you from drivers within 500 feet, move the far triangle back so they see it in time.
Tested:where to set out reflective triangles after stopping on a straight, level, undivided two-lane road, or beyond a hill or curve.
Paved or gravel strip beside the travel lanes for emergency use.
Most shoulders will hold a heavy truck, so steering onto one can be safer than a collision. Once there, avoid braking until you have slowed a lot, keep one set of wheels on the pavement, and stop before pulling back on. If you must return at speed, turn back sharply and then countersteer.
Tested:how to leave the road in an emergency, how to return from the shoulder, and when to set out triangles after stopping there.
Headlight setting that throws light farthest down the road.
Use them whenever it is safe and legal, because low beams show far less of the road ahead. Dim them when another vehicle is coming toward you or you are following one, and never answer another driver's glare with your own. In the pre-trip you check them with the dimmer switch during the light check.
Tested:when to use high beams, how far they reach, when to dim for other vehicles, and how to handle glare.
Headlight setting aimed low to avoid blinding other drivers.
You see much less of the road on low beams, so slow down enough to stop within the distance they light. Use them in daytime rain, snow, dusk and fog to be seen, and in the pre-trip you turn them on for the walk-around light check.
Tested:how far low beams let you see, the distance you must be able to stop within, and when to switch to them.
All four turn signals flashing together to warn other drivers.
The manual calls them four-way flashers. Turn them on when stopped at the roadside, when driving very slowly, in fog, and near work zones so drivers behind notice you. Laws on using them while moving differ by state, so check where you drive.
Tested:questions ask in which situations you should switch on the four-way flashers and how else to warn drivers behind you.
Straps, chains or ropes that fasten cargo to the vehicle.
On flatbeds they keep the load from shifting or falling off; in closed vans they stop cargo from moving and upsetting the handling. Use at least one tie-down for every 10 feet of cargo, and never fewer than two, however small the load. Their combined strength must be at least half the cargo's weight; see working load limit.
Tested:how many tie-downs a load of a given length needs, the minimum for any small load, and the total strength required.
Holding cargo in place with blocking, bracing and tie-downs.
A shifting load can roll a truck, break the cab's header board, or spill onto the road. Inspect it before the trip, again within the first 50 miles, and then every 150 miles or three hours, whichever comes first. The whole system must have enough combined strength for the load's weight; see working load limit.
Tested:how soon after starting you must recheck cargo, how strong the securement system must be, and what the pre-trip covers.
Blocks and braces that keep cargo from sliding or tipping.
Blocking is fitted tightly in front of, behind or beside a piece of cargo and fastened to the deck. Bracing is a strut from high on the load to the floor or trailer walls, so the load cannot tip or shift. Hazmat rules also call for blocking or bracing of cylinders and some packages.
Tested:why blocking and bracing are used, where blocking goes, and how compressed-gas cylinders may be loaded without racks.
Maximum load a tie-down or securement part is rated to carry.
Every strap, chain, hook and anchor point has a working load limit (WLL) marked by its maker. Add up the limits of all tie-downs on a load to get the aggregate working load limit. Federal rules say that total must be at least half the weight of the cargo.
Tested:what fraction of the cargo's weight the combined working load limit of the tie-downs must reach.
Not the same as:Not the breaking strength; the working load limit is well below the point where the strap fails.
The combined working load limits of all tie-downs holding one load.
Federal rules require this total to be at least half the cargo's weight. Count only the tie-downs actually holding that load, and use each one's marked limit.
tarp
брезент
A heavy cover tied over open cargo to protect it.
Flatbed loads are often covered with a tarp. It must be tied tight so it cannot flap, tear, or block your view.
Tested:how to check that a tarp is secured during inspection and what to watch for in your mirrors while driving.
Driving with your eyes, hands, or mind off the road.
Texting is the worst distraction because it takes your eyes, hands, and mind at the same time. Using a handheld phone in a commercial motor vehicle (CMV) is a serious traffic violation.
Tested:which habits prevent distraction, how to spot a distracted driver, and how phone and texting rules affect your CDL.
The amount of alcohol in your blood, a measure of impairment.
Your BAC rises with how much you drink, how fast you drink, and how little you weigh. The limit for driving a CMV is 0.04, and any alcohol below that still means 24 hours out of service. Only time lowers it; coffee and cold showers do not.
Tested:what determines BAC, the BAC limit for driving a commercial motor vehicle (CMV), and what happens below that limit.
Driving a commercial motor vehicle (CMV) counts as consent to alcohol testing.
You do not sign anything. By driving a CMV you have already consented. Refusing the test loses your CDL just like failing it.
DUI
DUI (водіння у стані сп'яніння)
DWI, OWI, driving under the influence, driving while intoxicated
Driving under the influence (DUI) is driving any vehicle while impaired.
Impaired means by alcohol or drugs; states call it DUI, DWI, or OWI. A first conviction costs your CDL for at least one year, three if the CMV was placarded for hazmat. A second conviction costs it for life, and a conviction in your personal car counts too.
Tested:how long you lose your CDL after a first and a second conviction and whether a personal-vehicle conviction counts.
The highest legal speed on a road, shown on a sign.
Trucks and buses may have a lower limit than cars on the same road. A curve's posted speed is set for cars; a tall, heavy truck can roll over at that speed.
Tested:how to choose speed in heavy traffic, on curves and downgrades, and which speeding offenses count as serious traffic violations.
A speed that lets you stop within the distance you can see.
Safe speed is often below the speed limit. Rain, curves, hills, traffic, and poor visibility all lower it. On a downgrade, pick it before you start down.
Tested:how to pick a safe speed for curves, downgrades, and heavy traffic, and what factors should set it.
It is for dry, open roads with steady traffic. Turn it off on wet or icy roads, on downgrades, and in heavy traffic, where you need full control of speed.
