Converter dollies: The trailer is at the correct height when. You should be sure the converter dolly air tank drain valves are _______ and the pintle hook is _____. C When driving a double or triple trailer, greater care must be given to. kingpin. B. closed A. brake and downshift in a curve The trailer height is right when: The trailer will be raised slightly when the converter dolly is backed under it. If loading fails, click here to try again. You should NOT: Your tractor protection valve control should pop out, or go from normal to emergency position, when air pressure falls into what range? Which of these is the correct answer? Typically depends on the axle count. A. allow "much more space" than is needed for ideal driving conditions How do you know if your converter dolly is equipped with antilock brakes? How To Use Cruise Control Effectively As A Truck Driver. Allow much more space than is needed for ideal driving condition. The DMV doubles triples practice test will examine your knowledge of pulling double/triple trailers, coupling and uncoupling, inspecting doubles and triples, and checking air brakes. You need to stop braking because it's necessary for you to speed up, When you are in a drive-wheel braking skid, the first thing to do is STOP BRAKING! Any time you have to A safe speed on a curve for a straight truck or a single trailer combination vehicle may be too fast for a set of doubles or triples. Newer trailers have spring brakes just like trucks and truck tractors. The converter dolly air tank drain valve on coupled double and triple trailers should be: Closed. C. always keep your vehicle to the left side of your lane, When testing the coupling of double trailers, the landing gear of the rear trailer should be: Once you have coupled your rear trailer, you should test the coupling by? A. air escape from the open valve When checking the fifth wheel, you should make sure that it has enough? A Which of these is most likely too occur? NPT thumbscrew style design enables easy installation. View More Details. rear brakes will not work properly. 0000009556 00000 n 27. cQ 220rd8bihuM#Om>G*Lz)g^\l9'A9/omf|b49U[@%jGT-QR6i. When driving with more than one trailer, which trailer should be the first one behind the tractor? Once you are finished, click the button below. A. use a low gear Older trailers do not have spring brakes. Join 50,000+ users around America to get your Commercial Driver License today! C. use a light touch on the accelerator and brake pedals, For coupled double and triple trailers, all of the converter dolly shut-off valves should be: Why should you pull a dolly out from under a trailer before you disconnect it from the trailer in front? and ensuring it is secure. A bent or damaged kingpin on a coupling should be? The total number of questions. Make sure you can hear air escaping with the valve closed. You should look into the back of the fifth wheel on a dolly to see if it is locked onto the kingpin, A safe speed on a curve for a straight truck or a single trailer combination vehicle may be too fast for double or triple trailers. Watch the wording of the question AND the answers A safe driver will look for all of the above. The application only takes one minute. 0000008915 00000 n B This section explains how important it is to be careful when driving with more than one trailer, how to couple and uncouple correctly, and about inspecting doubles and triples carefully. A 360 degree area of awareness is If this lamp is illuminated and does not go out, You should hear air escaping, showing the entire system is charged. Use the dummy couplers when the air lines are not connected to a trailer. What value of channel width must the design use? Then, the air loss from the leak will lower the air tank pressure quickly. It is important to check the height of the trailer before connecting a converter dolly to a trailer. When entering a roundabout, a driver must yield the right-of-way to drivers already in the roundabout and obey all traffic signs. Explain why the waves that reflect from the far left edge of the plates in the given figure earlier exhibit destructive interference (zero intensity) at x=0x=0x=0. A. Select the answer that correctly completes each statement. B. keep gentle pressure on the brakes while going through the water and for a short distance after coming out The A-dolly has a single drawbar with a single, centered hitching point. Air flows steadily and isentropically through a passage. While doing a walkaround inspection of a double or triple, the converter dolly air tank drain valve should be _____, and the pintle hook should be _____. Take special care when pulling two and three trailers. What is the most common foundation brake found on heavy vehicles? driven with care to avoid losing control, Make sure the spare tire is secured, if it has one, Make sure the converter dolly air tank drain valve is closed, Make sure safety chains are secured to the trailers, All of the above. A. the total stopping distance of a truck is the distance it takes to stop once the brakes are put on at any speed You are doing a walk around inspection of a double or triple trailer rig. If you want to couple a second trailer to your combination vehicle, secure it by using: The crack-the-whip effect that troubles trucks with trailers is most likely to cause a tip over: You are driving on a slippery road during the day. TestPermit.com provides free unofficial review materials for a variety of exams. Use controlled or stab braking 8. Open. What's a converter dolly? If one air system is very low on pressure _______. There are two types of converter dollies. Shut off valves are only used on trailers designed to be towed in conjunction with other trailers (doubles / triples). you are visually checking the coupling of a converter dolly to the rear trailer. How can you test that air flows to all trailers? That there is no space between upper and lower fifth wheel. Studying and applying oneself is the only way to successfully learn the information you need to know to pass all testing required to obtain your CDL. To test the tractor protection valve, charge the trailer air brake system, turn off the engine, and speed and start spinning again, in turn stopping your skid, All the listed answers would be correct. After 15 years on the road I wanted to help people understand the trucking industry and everything that came with the career and lifestyle of an over the road trucker. You can reset the test and retake it as needed. The rear trailer of a triple Often do not have spring brakes None of the above, 5. When coupling twin trailers, a converter dolly is. Doubles and triples must be driven very smoothly to avoid rollover or jacknife. For all brakes to work on a triple combination, you must have air supply? Have little braking power because they are small The individual voltage gains of the first two stages are to be equal, while the gain of the third is to be one-fourth of each of the first two. 0000010783 00000 n 1/4 in. We've all wondered if the adventure and challenges of life on the open road would suit us better than the ordinary day to day lives we've always known. If you do, there is a problem. For emergency braking you should: You are doing a walk around inspection of a double or triple trailer rig. B When you do this, you should hear: Always unlock the pintle hook with the dolly still under the rear trailer. what is likely to happen if the pintle hook is unlocked with the dolly still under the second trailer? B. slow to a safe speed before entering the curve, then accelerate slightly through it how much space should be between the upper and lower fifth wheel? You should be sure the converter dolly air tank drain valves are _____ and the pintle hook is _____. you are driving a 100ft truck eith double trailers at 50mph. symptoms of a bad fuel tank selector switch. Flammable materials in the front trailer then it must have the placards on that trailer. In normal operation, trailer service brakes should be operated by? 1. Also available in App Store & Google Play. A. you can steer more quickly and safely if you hold the wheel with one hand Safety chains should be secured to trailer(s). Remember: The trailer air brakes are supplied with air using the emergency line (also called the supply line). When connecting a converter dolly to a rear trailer, the trailer height must be adjusted so that it is? B. restore traction to the tires They are not only longer, but also need more space because they cannot be turned or stopped suddenly. 0000001354 00000 n Safety fail-safe features of a tractor-trailer converter dolly. When connecting two trailers the converter dolly is connected to the rear trailer first. During normal operation the brakes of the double/triple trailer are controlled by: You are driving at night and you must dim your headlights for traffic. Each tank has a drain valve on it, and you should drain each tank every day. %PDF-1.2 % On a triple combination, the shutoff valves at the rear off the middle trailer should be? The application only takes one minute. You have not finished your quiz. Those that do not have spring brakes have emergency brakes that work from the air stored in the trailer air tank. C. use controlled or stab braking, The best way to stop any skid is to: We'll help you make the right choices and prepare for a great start to your trucking career. Each trailer and converter dolly has one or more air tanks. Doubles and triples must be driven very smoothly to avoid rollover or jackknife. How do you know if your converter dolly is equipped with antilock brakes? The couplers have a rubber seal that prevents air from escaping. The road is dry, and visibility is good. should remain in the closed position. to do this without wheel chocks you should: supply air to the trailer air system with the tractor and then disconnect the emergency line. Which of these statements about quick steering movements and doubles/triples is true? inspection of all equipment. 0000010705 00000 n C If there are no dummy couplers, the glad hands can sometimes be locked together (depending on the couplings). A C. fully raised, Which of these statements about speed management and braking is true? There is no obligation whatsoever. how can you be sure you supplied air to a second trailer? C. add "one car length for every 10 mph", Fundamentals of Engineering Economic Analysis, David Besanko, Mark Shanley, Scott Schaefer, Incidental Motions & Motions that Bring a Que. C. engaging the tractor valve protection control, You must drive through deep or flowing water. Closed, free, 8. re-couple, You can if you want to, it does not matter. Nothing will happen, but an in-cab warning indicator will let you know about the problem, It will cause the tractor protection valve to close and the trailer emergency brakes to come on, It will cause the tractor protection valve to open and the trailer emergency brakes to come on, When you try to put the service brakes on, air will quickly leak and will lower the air tank pressure, possibly activating the trailer emergency brakes, The emergency brakes will come on automatically as soon as a major leak occurs, Nothing, but braking power will be reduced, Air pressure will quickly leak away, even if you are not using the service brakes, Using a combination of the emergency air line and the service air line, Supply air will be sent to the service line instead of going to charge the trailer air tanks which means the trailer spring brakes will not release, Newer vehicles automatically detect if the lines are crossed and will auto-correct itself, Air will continue filling the air holding tanks until the tanks rupture from excessive pressure, Supply air will cause all brakes to release and the truck will roll freely without any braking ability, Trailers typically do not have their own air tanks, Designed to turn off the truck engine when a brake failure occurs, Used in the service and supply air lines at the back of trailers used to tow other trailers, Placed at each trailer spring brake and are designed to engage the emergency brakes when air pressure becomes too high, The yellow and red air control knobs located in the cab of a truck, Used to secure the trailer kingpin to the tractor 5th wheel, Caps which cover the valve stems on tires, A name for the yellow and red air valves in the cab of a truck, Coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer, Email Updates When New Articles Are Posted. retrovirus $_____________________________$. 1. To help avoid mistakes, colors are sometimes used. open the shut-off valves at the rear of the first trailer and close the shut-off valves at the rear of the second trailer, enclose converter dolly air tank drain valves D Should I Be A Truck Driver? 60607. To do this without wheel chocks you should: When uncoupling the rear semitrailer, you should lower the converter dolly landing gear: When driving a double or triple, you need more space because they: Which of these statements about emergency steering is true? For emergency braking you should: . When testing trailer service brakes, you should use? A CDL is required to drive any of the following vehicles: A vehicle with two separate parts - the power unit (tractor) and the trailer. [Flashing Signals, Traffic Signals, Chapter 5 - Signals, Signs and Pavement Markings, North Carolina Driver's Handbook], One component of the DUI sentence in the state of Tennessee is twenty-four hours of litter pick-up wearing clothing that says "I am a drunk driver." This has the same value as the %%PERCENTAGE%% Variable on the Final Screen. The crack the whip effect will topple the rear trailer first. a. blood Therefor, if there is a major leak in your service line, you may not know it until you try to use the service brake. Converter dolly air tank drain valve: CLOSED. The converter dolly air tank drain valve on coupled double/triple trailers should be: You are driving a 100-feet truck with double trailers at 50 mph. Which trailer should come first behind the tractor? When the road is slippery you are driving a set of doubles and a set of trailer wheels goes in a skid. The braking systems of double and triple trailers are different than those of straight trucks because doubles and triples. second trailer will be connected, The dolly will have a yellow lamp on the left side, The dolly will have a yellow lamp on the right side, The dolly will have a red lamp on the left side, The dolly will have a red lamp on the right side. When inspecting doubles and triples you must make sure there is air all the way to the back of the last trailer, otherwise what may not work? You MUST have air all the way to the back for all the brakes to work. This has the same value as the %%TIME_USED%% Variable on the Final Screen. trailer << /Size 59 /Info 20 0 R /Root 22 0 R /Prev 29211 /ID[] >> startxref 0 %%EOF 22 0 obj << /Type /Catalog /Pages 19 0 R >> endobj 57 0 obj << /S 66 /Filter /FlateDecode /Length 58 0 R >> stream 2) the second test is to go out to the trailer to ensure that the parking brakes have indeed applied. You need to brake in order to regain control. Contributor: Luke Nold (Experienced truck driver for 5+ years and published writer for Fleet Magazine). Because of this, which of the following vehicle parts is most likely to tip over? However, converter dollies and trailers built before 1975 are not required to have spring brakes. Describe what the trailer air supply control does. The front trailer in a set of double trailers is most likely to turn over due to the Crack-the-Whip effect. In an application in which vGS=vDS=Vsupply=1.8V,v_{G S}=v_{D S}=V_{\text { supply }}=1.8 \mathrm{V},vGS=vDS=Vsupply=1.8V, a drain current of 2 mA is required of a device of minimum length of 0.18m.0.18 \mu \mathrm{m}.0.18m. Make a sketch that explains this phenomenon in terms of a feedback loop . Why should you not use the trailer hand valve while driving? 0000008187 00000 n ), a 15 year truck driving veteran, in January 2007. if you have traffic on both sides of your vehicle and something is blocking your lane, a move to the right still be best. The final procedure when connecting a rear trailer is to? If a converter dolly is still under the second trailer and you unlock the pintle hook, what will probably happen? Ship to Store. If not, there is a problem. Sometimes, metal tags are attached to the lines with the words service and emergency stamped on them. This will let the rear wheels roll again and keep the rear wheels from sliding. The rear trailer of a double Pintle-eye of dolly in place in pintle hook of trailer (s). You should keep at least ____ seconds of space ahead of you. In double and triple trailers, the trailer air supply control should pop or _________ when air pressure drops into the range of 20 to 45 psi. you are doing a walkaround inspection of a double or triple trailer rig. Our business address is: Attn: Class A Drivers MH Sub I, LLC dba Internet Brands 909 N Pacific Coast Highway, 11th Floor El Segundo, CA 90245. Any vehicle, regardless of size, designed to transport 16 or more persons, including the driver. The lightest trailer The lighter semitrailer should be in first position behind the tractor. A The shut off valves prevent air from going any further. Question 3 Explanation: All of the above. When you're trying to correct a drive-wheel braking skid why should you stop braking? The dolly will have a yellow lamp on the drivers (left) side. Open the emergency line shut-off valve at the rear of the last trailer. It is extremely unlikely you will drive a trailer built before 1975, but for the written exam, you still may need to know that trailers built before 1975 were not required to have spring brakes. A. make things look smaller and farther away than they really are A What is most likely to happen if the trailer protection valve of a double or triple trailer does not function correctly? When checking the coupling system, make sure that the locking jaws are around the shank of the. When you do this, you should hear: Ais escape from the open valve. Never, 9. The air lines will rupture There are more things that can go wrong, and doubles/triples are less stable than other commercial vehicles. 0000002446 00000 n some large trucks have curved (convex or spot) mirrors. A driver of a vehicle with double or triple trailers will have greater length and more dead axles to pull, increasing the likelihood of a wreck. B you are driving on a slippery road during the day. C. open, except the one connected to the rear trailer should be closed, During normal operation the brakes on double and triple trailers are controlled by the: Becoming A Truck Driver is a dream we've all pondered at some point in our lives. How many different ways of coupling and uncoupling trailer combinations are there? How can you test that air flows to all trailers? Doubles and triples are more likely to turn over than other combination vehicles because of what effect? If you do cross the air lines, supply air will be sent to the service line instead of going to charge the trailer air tanks. If it goes low enough, the trailer emergency brakes will come on. These valves permit closing the air lines off when another trailer is not being towed. - Converter dolly air tank drain valve: CLOSED. For emergency braking you should: slow to safe speed before entering, then accelerate slightly through the curve. B You must treat a flashing red signal as you would treat a STOP sign. Unless you are draining the condensation out of the air tank, then the drain valve You must check that all shut-off valves are in the open position except the ones at the back of the last trailer, which must be closed. Do converter dollies have spring brakes? Locking jaws open front of the second trailer. It is very important to keep the air supply clean. If the converter dolly is close to your semitrailer, you should wheel it into position? This has the same value as the %%TIME_ALLOWED%% Variable on the Final Screen. You wish to turn right from one two-lane, two-way street to another. B. The crack the whip effect that troubles trucks with trailers. You should not hear air escaping. The emergency brakes come on whenever air pressure in the emergency line is lost. which of these statements about the handling of doubles and triples is true ? When inspecting the air brakes on doubles and triples, you wait for air pressure to reach normal, then push in the red trailer air supply knob. Number of wrong answers. 0000001107 00000 n Hit the article to see the way to back up your trailer like a pro! The road is dry and visibility is good. King pin. Closed, latched The driver must yield the right-of-way to other vehicles when merging and when entering a highway from an alley. Wait for air pressure to reach normal, then push in the red trailer air supply knob. You are visually checking the coupling of a converter dolly to the rear trailer. If this activity does not load, try refreshing your browser. B. are the easiest to stop since there is no shifting cargo Remember, the service line is not used unless you depress the brake pedal or use the trailer hand valve. C. posted speed limits on curves are safe for all trucks, Empty trucks: Which f these will result in the best control on curves? Open All rights reserved Site Map. What happens when there is a major leak in the emergency air line? Double and triple trailers increase not only the operators risk of safety, but also the other motorists around him. can and will get stuck on a raised railroad crossing. A. always keep your vehicle to the right side of your lane C. 3, You are doing a walk around inspection of a double or triple trailer rig. Time allowed (Requires timer add on). 6. The pintle hook should always be secure when the vehicle is in motion.