| Author | Message | ||
| david anderson (Davidanderson)
Rating: N/A |
Just for information, I installed my dinghy brake system for my pickup. I didn't even know I needed one until I saw this: http://www.roadmasterinc.com/laws.htm I bought the air brake system and brake away stop system from: http://www.hendersonslineup.com/contactus.htm The SS011 Superstop Fitzal was 449.95 and the SS004 Brake away system was 256.23. You can buy the braking system without the break away system but not vice versa. It took me about 8 hours to install the system. I tapped into a 1/4" plugged hole on my rear brake valve to supply air to the rear bumper area. Drilling and mounting the hardware on the pickup took most of the time. The bus part was easy. I'm using the toad's brake lights for stop lights, since the Fitzal pushes the brake. For tail lights, I'll turn on the toad's parking lights. I ran two relays for turn signals. The bus powers each relay coil for right or left signals. I tapped into the toad's turn signals right next to the headlamps. No diodes, etc. I don't even have to pull the fuse since the toad provides the power to the signals. The bus just flashes the relay coils. I ran a 3rd relay on the load side of the toad's brake light. This closes a contact on a ciruit to an indicator light on the dash of the bus to show brake actuation. This way I know if the pedal is pressing in and out or stuck down. I'll feel safer now when driving out to Busin USA in Oregon in July. David Anderson | ||
| Geoff (Geoff)
Rating: N/A |
The chart you looked at is for trailer brakes-- toad brakes fall under a different catagory and is not usually specifically addressed, so the general opinion is that they are not required. See: http://www.towingworld.com/brakinglaws.html BTW, I don't have any brakes on my toad and don't need them. --Geoff '82 RTS CA (back from Arizona, 2850 miles without toad brakes!) | ||
| Sean Welsh (Sean)
Rating: N/A |
Umm, Geoff -- if a state doesn't have a specific law for Toads, they are usually considered trailers. If a trailer needs brakes, then so does a Toad of the same weight. I can't speak for whatever state you are in, but I know unequivocally that this is the case in CA and WA. I'm not sure what "general opinion" you are citing. David -- this comment concerns me: "I tapped into a 1/4" plugged hole on my rear brake valve to supply air to the rear bumper area." If you ran an air line all the way to your toad, I'm hoping you installed some sort of protection valve ahead of it in the event the air line is severed. Not only is this required by law, it is also an important safety issue -- if the line breaks, you'll experience either a full, immediate spring brake application, or a complete loss of one of your two service brake application loops (depending on what kind of brakes you have), either of which can result in loss of control. Also, your plan to use the brake, running, and turn lights on your toad from the toad's own battery may be problematic, unless you have a way to keep that battery charged (such as running the toad's engine while it is under tow). I think you'll find that just a couple hours of running lights combined with brake usage can eat your battery. FWIW. -Sean | ||
| Bob Sheaves Rating: N/A |
Sean, I haven't investigated Washington. What's the basis of your blanket statement in view of California Veh.Code §26458(c)(3)? By my reading of the statute, if the combination still satisfies the stopping distance tests established by another code section, the above section provides an exception | ||
| John that newguy Rating: N/A |
California 26508-(a) "Every motor vehicle operated either singly or in a combination of vehicles and every towed vehicle shall be equipped with an emergency stopping system. " http://www.dmv.ca.gov/pubs/vctop/d12/vc26508.htm | ||
| John that newguy Rating: N/A |
ahhhh.... whooops: California = "Baking System: Towing Vehicles 26458. (a) The braking system on every motor vehicle used to tow another vehicle shall be so arranged that one control on the towing vehicle shall, when applied, operate all the service brakes on the power unit and combination of vehicles when either or both of the following conditions exist: (1) The towing vehicle is required to be equipped with power brakes. (2) The towed vehicle is required to be equipped with brakes and is equipped with power brakes. (b) Subdivision (a) shall not be construed to prohibit motor vehicles from being equipped with an additional control to be used to operate the brakes on the trailer or trailers. (c) Subdivision (a) does not apply to any of the following combinations of vehicles, if the combination of vehicles meets the stopping distance requirements of Section 26454: (1) Vehicles engaged in driveaway-towaway operations. (2) Disabled vehicles, while being towed. (3) Towed motor vehicles. (4) Trailers equipped with inertially controlled brakes which are designed to be applied automatically upon breakaway from the towing vehicle and which are capable of stopping and holding the trailer stationary for not less than 15 minutes. Amended Ch. 121, Stats. 1991. Effective January 1, 1992. " http://www.dmv.ca.gov/pubs/vctop/d12/vc26458.htm Confusing, huh? It's Cally-forny-ya! | ||
| Geoff (Geoff)
Rating: N/A |
I guess all tow trucks are going to have to install auxillary tow brakes on every car they tow in California? A towed car has never had to have a braking system in CA as long as I remember. | ||
| Bob Sheaves Rating: N/A |
Its not confusing when you separate the "apples from oranges" arguments. In the Peoples Republic of Kalifornia (PRK): A towed vehicle doesn't need to have its service brakes actuated in conjunction with the towing vehicle, if it can satisfy the stopping distance criteria set forth elsewhere in the code However, a towed vehicle appears to require a mechanism to actuate emergency brakes in the event of a disconnect while underway. By anaolgy, it appears that if the towed vehicle was under 3000# it wouldn't require brakes. | ||
| david anderson (Davidanderson)
Rating: N/A |
Sean, The tap is on the port of the valve that is proportional to brake pedal pressure as per Fitzal recommendation. The line is encased in a sleeve an securely tied to the frame from the valve to the bumper. Yes, if it was severed it would leak air, but only if the brakes were applied. I would show an abnormal bleed off of air on my rear gauge if this happened. However, I would have enough time to exit the hiway without a spring brake lockup. Also, if that happened the dash light would not illuminate since the toad brake would not be pressed, another indication of something awry. I'm not clear on how one would install a protection valve in this application. Please enlighten me. Thanks for your concern. David Anderson | ||
| Sean Welsh (Sean)
Rating: N/A |
Bob, Your reading of the code is correct, there is a specific exemption from service brake application for towed motor vehicles (as that term is defined in the code) if the combination can meet the specified stopping distance listed elsewhere (which, by the way, is 50 feet from 20mph, fully loaded "at any time," which means, BTW, on any surface). In practice, it's nearly impossible to meet the 50 foot requirement on certain surfaces, but, in any case, the burden of proof is on you the operator, and not the state. Whereas, by having the proper brakes, your vehicle is presumed to be in compliance with the towed vehicle braking standards (even though, theoretically, you can be asked to prove the 50' requirement as well). None of which exempts you from the break-away requirements of 26508(a) (assuming your coach has air brakes), which does not carry a similar exemption. While it's possible to outfit a "towed motor vehicle" with a break-away braking system that does not also function as a service brake, in practice, most systems are combination units. And if you have to fit the break-away system anyway, why not hook up the service brakes as well, and be in compliance with 26458(a)? Geoff -- "tow trucks," as those are defined in the code, are explicitly exempted under 26458(c)1 and (c)2. If you, as a private citizen, bought a wrecker, you couldn't tow cars with it without first being licensed as either an emergency road service, or an auto dismantler. A wrecker is not a "tow truck" under CA law unless it is operated by a properly licensed entity. David -- OK, I understand now how it's connected. So it's the latter part of my statement that applies: you would not have a spring brake application, but, rather, a major loss of service brakes on that loop (i.e. if the hose rips off, then that service line will be open to atmosphere). All of which suggests that the system you have has some different way to detect break-away to meet that part of the requirement. Protection valves generally depend on there being an always-pressurized line to the trailer. It is the complete loss of pressure in this line that engages the protective mechanism, shutting off all air flow to the trailer. With your setup, I would think that a relay valve and a small auxilliary tank could be used. The service application line would activate the relay valve, which would then supply air to the trailer system from the aux tank. You would fill the aux tank from upstream of the brake tank check valves. This would absolutely ensure that a severed hose on the trailer could not bleed off application pressure from either of your service lines. -Sean | ||
| FAST FRED Rating: N/A |
EZ , just get a really LIGHT towd. FAST FRED | ||
| T. (Bluegrass)
Rating: N/A |
OK you guys know how a semi Tractor works, It runs through the Tractor Protecion Valve ( That Is manualy operated from the Inside of the Truck) to the pressure in the service line, why not do the brakes this way. | ||
| Jtng Rating: N/A |
Sean- 26508. Every vehicle or combination of vehicles using compressed air at the wheels for applying the service brakes shall be equipped with an emergency stopping system meeting the requirements of this section and capable of stopping the vehicle or combination of vehicles in the event of failure in the service brake air system as follows: (a) Every motor vehicle operated either singly or in a combination of vehicles and every towed vehicle shall be equipped with an emergency stopping system. --clip-- "(m) The provisions of this section shall not apply to: (1) Auxiliary dollies, special mobile equipment, or special construction equipment. (2) Motor vehicles which are operated in a driveaway-towaway operation and not registered in this State. (3) Disabled vehicles when being towed. " From http://www.dmv.ca.gov/pubs/vctop/d12/vc26508.htm | ||
| Brian (Bigbusguy)
Rating: N/A |
David , It look likes its a good system I was thinking about building one like it using a spring brake can for my air cyl to push on the brakes. I would like to check it out at the rally I will be there but may leave my bus out side and walk in. Lots of BS about if need or dont need one. I think it one of the best things you can do for towing any thing with your bus law or no law. I think one test you can do to see how much brakes you have is on some long empty road unhook the air line and let it blow get up to 20 mph or so and see what happens. I think you will have lots of stoping power sill left even with the air line off. Also the Tractor Protecion Valve would not work with one line the way David has set up also It will not work if only the service air line has a hole or comes off on a truck. Its use on truck is if the trailer comes off and both lines seperate you dont lose the air or brakes. The one Im going to build will be just like towing a semi trailer with air brakes So it will have both air lines, a trailer parking valve up front and a Tractor Protecion Valve . And have one spring brake can to push on the brake pedel. I dont care about any law or code I just want to stop as fast or faster with a towed. I dont know why people are wasting there time looking up laws and rules ? YOU STOP FASTER with a towed brake why do you even need a law or rule to make you put on somthing to make you more safe?? Brian 4905 | ||
| Sean Welsh (Sean)
Rating: N/A |
JTNG, You need to go look up what a "driveaway-towaway" operation is.... One needs to have manufacturer or distributor license plates to qualify for that exemption, and the vehicles involved need to be being "delivered" as "product." This exemption is used principally to deliver truck frames... you know, the times you see a truck cab, and behind it is another truck cab that looks like it's, umm, "humping" the first one, and behind that is maybe yet another one. Although, technically, those guys who deliver new motorhomes from the factory get to use this as well. It most decidedly does not apply to normal citizens pulling toads with their motorhomes. BTW, anytime you see a term like this in the CVC, go up to the section on "definitions" to see how California defines the term. There is a very specific meaning in California for terms that you and I might understand differently in everyday speech, such as "tow truck," "bus," and "house car." -Sean | ||
| John that newguy Rating: N/A |
Sean- My error, you are correct. The towed vehicle must be a commodity to be considered a driveaway-towaway. The bottom line? The Republic of Kalifornia does not require a towed vehicle to have service brakes operated by the towing vehicle, but it does require an emergency break-away system. (Ca laws pertain to Ca registered) Taa-dah. Done. And yes, It'd be nice to have a towed vehicle braking system, if one can afford it. If not, safety chains have worked well and will continue to work well... for those of us that cannot afford dumping another grand or more into the project. WAGONS HO - TOW AWAY, MEN | ||
| Jim Ashworth (Jimnh)
Rating: N/A |
Brian 4905- be careful what you use for a brake "can" to push on the brake pedal. The smaller ones for busses are 30 sq in. If only 40 psi is applied, that's 1200 pounds of pressure on the brake pedal. I wonder if movement will stop when the pedal hits the engine? Research fully what you are thinking about doing. Jim | ||
| Chuck Newman (Chuck_newman)
Rating: N/A |
Sean, Speaking of definitions: For kicks one day I was comparing CVC definitions of "house car" and "motorhome". I could not find any difference of substance. At the time I was thinking of re-registering my van towed as a motorhome. It appears the criteria is basically the same under each definition. Interestingly, I recently found a registration for an old motorhome I had. It was registered (in CA) as a house car. Last year when I registered the bus, I specified motorhome on the DMV form, and that's the way it is listed. Now that I think of it, the old motorhome listed as a house car was probably due to the seling dealer checking that box on the form. Your take on house car vs motorhome in CA. Thanks, Chuck Newman Oroville, CA | ||
| Sean Welsh (Sean)
Rating: N/A |
Chuck, The CVC does not recognize the term "motor home." Officially, California calls them "house cars," although I have seen the term "motorhome" on some official printed publications, including from the DMV. As far as the code is concerned, it's a "house car." AFAIK, there is only one registration category for them. (Side note here: the DMV uses a cryptic coding system for many things, and this system is not published anyplace that I have ever been able to discern. I've been around and around with them on several vehicles over the years, after I discovered that some indecipherable notation on a title did not correspond to the reality of the vehicle in question. The CHP, by the way, which is subject to much greater public scrutiny, uses a completely different set of notations. Often it is the dispatcher back at the communications center who has to sort the specifics out during a traffic stop. FWIW.) -Sean | ||
| Chuck Newman (Chuck_newman)
Rating: N/A |
Sean, I know the cryptic "vehicle class" codes. I have noticed they sometimes change from one year to the next. Not surprisingly, most DMV employees don't know what they mean. When I was a reserve Deputy Sheriff, I noted the most common vehicle types on the computer were: SD=sedan, CP=coup, PU=pickup, TR=trailer, MH=motorhome, and others. For information, for speed laws, the CHP considers a towed to be a trailer. They have case law to back it. On the braking issue, most CHiPies don't get concerned about brakes unless you are in an accident. Then they look at everything. So does the insurance company. Chuck Newman Oroville, CA | ||
| FAST FRED Rating: N/A |
"I dont care about any law or code I just want to stop as fast or faster with a towed. I dont know why people are wasting there time looking up laws and rules ? YOU STOP FASTER with a towed brake why do you even need a law or rule to make you put on somthing to make you more safe?? " The usual GM is operating well below its GVW, on our 06 we run 24,000 camping and about 28,000 when shutling north & south every year. Towing a 2500 lb VW with a 24,000 coach the car isn't noticable at all. AS the chasis was made for 32,000 , the stoping at 24,000 to 28,000 doesn't seem to change a bit. For faster tire wear while stoping a different treadle valve can be installed , that will lock up the tires. Attemping a quicker stop using an augment from the Towd , seems like a hard way to go. Keep it light!!And it will stop!(and GO better to!) FAST FRED | ||
| Brian (Bigbusguy)
Rating: N/A |
FF, I was talking about towing a real car or suv. And you may not noticed but it does put more wear on you bus brakes and tires to stop more weight even if its just a little 2500 lb toy car with out having brakes on it. And my bus brakes and tires cost a lot more then a store bought braking system. My truck is almost 4000 lb and my bus is 10000 lb under GVW and it is noticable in extra air psi needed to stop with out towed brakes. You make you numbers you list sound good but in a true full service brake stop the more weight you have the longer it will take you to stop it dont matter where the weight is in the bus or behind the bus. More brakes the faster you stop and also the brake away saftey in stoping your car before it crashes in to a street sweeper. Stops for me Brian 4905 | ||
| Jim Bob Rating: N/A |
Brian, we tow an Explorer with our "antique" 4104. The Explorer would have to be classified as a "real car", being about 4,000lbs. The 4104 weighs 24,500 fully loaded and has an axle rating of 32,000 max. By weight, it could carry two Explorers & still be within the design weight. We can hardly tell the car is back there, the only perception is a tiny little "tug" when we shift gears. We notice no difference when slowing down. It's kind of like a Chihuahua tied behind a Great Dane. You know, GM buses are built with a break treadle valve that won't let the brakes lock up on dry pavement. This has been the subject of cursing & praying in our bus in panic stop conditions but it does brake hard enough to throw any unsecured items in the bus at the dashboard. The motor vehicle laws were primarily written for cars, light trucks & factory motorhomes which are usually pretty marginal on braking when towing something heavy. They absolutely need brakes on the towed item. But you are hearing busnuts debate the need for towed brakes because bus brakes are not marginal and folks who have towed a lot know that. And many of the systems cost WAY more than they should. That being said, breakaway stopping is a great thing to have on anything over 1,000 lbs. And these days, a person is crazy if they don't have legally mandated safety equipment. In court, it won't matter a bit that in reality the lack of towed brakes had nothing to do with your accident. The other guy's lawyer will paint a really bad picture of you as a guy who knew they were required but ignored the law. A jury of folks who know nothing about vehicles but might resent you because you own a big motorhome & therefore must be rich, will not be on your side. (Maybe there's a good argument that in a case like this that "A jury of your peers" would have to have some motorhome owners on it"!) | ||
| Marc Bourget Rating: N/A |
I've been following this thread with interest because an essential point about Physics has been omitted. While "hidden" from normal perception, this is simple, very basic, vehicle dynamics stuff. One of my original SCCA instructors, (before I became one) is an accident reconstruction expert. I'll break my self-imposed silence on bus related issues to further illustrate a non-bus related point Assuming the vehicle doesn't lack for sufficient braking capacity, additional weight ON THE BRAKED WHEELS/AXLES does not extend braking distance. This is so regardless if a bus starts at 5000# below or 10000# above its GVWR. However, additional weight added to unbraked axles in combination with the braked axles will extend the braking distance The reason Brian observed higher air pressure on stopping is because a greater use of the bus' reserve "brake capacity" (short of maximum performance) was required. All else being equal, adding weight equivalent to the tow'd on the BRAKED AXLES by placing sandbags in the bays/cabin, would see the pressure guage dropping back to the original value. The fact that this thread progressed for so long in the absence of this clarification is another illustration of the "cost to the BB" of the flight of the "smart guys". | ||
| Brian (Bigbusguy)
Rating: N/A |
"by placing sandbags in the bays/cabin, would see the pressure guage dropping back to the original value" Thats 100% wrong adding weight does not return the stoping distance to before the added weight of towed with out brakes what BS. Ask a expert. I will put money on that that Im right. Any added weight adds to the stoping distance in a panic stop. "accident reconstruction expert" I dont buy that after that post. Jim bob, My brakes will lock up on dry pavment so far. I dont know about yours why not this is the first time I heard that. If I did not have to go to work I would say more. Brian 4505 One of the "smart guys" almost. | ||
| Marc Bourget Rating: N/A |
Brian, Why ask an expert? You only have to duplicate the test! This one's simple! I think you missed my point. The "BS" arises from jumping to conclusions and not considering, accurately, the point I offered. The point offered was a fact based, intellectual point, not some slight against you. We're not talking about adding weight, making it a test between two different vehicle weight configurations, we're talking about a single vehicle of the SAME weight WHILE EXAMINING THE EFFECT of whether the added weight is borne by braked axles or unbraked axles. The list of experts includes Tom Lepper, E. Pejack, Ph.D and Bob Sheaves BA-ME. Tom travels routinely about the country consulting on large $$ cases. E. Pejack, Ph.D., was the designated reconstruction expert for Allstate in Northern California for many years, also in big $$ cases. Bob Sheaves, with a 30+ year history in engineering and vehicle design, designed the current live axle front suspension for the Dodge 4x4 Pickups back in '92 or so. That design received numerous awards for it's perfomance and handling capabilities. Do you wish to re-consider your point? | ||
| Stan Rating: N/A |
"Assuming the vehicle doesn't lack for sufficient braking capacity, additional weight ON THE BRAKED WHEELS/AXLES does not extend braking distance." That statement is going to make a lot of drivers rethink their stopping distance. I think every truck driving school teaches that it takes a greater distance to stop a loaded truck than when it is empty, with all else being equal. I am not disagreeing with your experts. It is all the driving schools that need to be told. | ||
| Marc Bourget Rating: N/A |
Stan, I think your missing the point. Despite your qualification, "all the driving schools that need to be told" you're disagreeing with my point by offering a position from a competing expert opinion source. Contrary to the poor interpretation and jumps to conclusion(probably because I didn't describe it clearly enough - but how clear is "clear"?) I never disagreed with the statement that Heavier vehicles take longer to stop. My position is a 48,000 vehicle, unless the brakes on a particular axle are overloaded will stop in the same distance, irrespective of whether 20,000 lbs is on the front, drive or tag axle, with the balance divided in any proportion between the remaining two axles (once again, as long as no axles' brake capacity is overloaded). A 48,000 vehicle, 40,000 lbs of bus and 8,000 of un-braked Tow'd, will not stop in the same distance. Put the tow'd on the roof of the bus (adding the weight of the tow'd to the braked axles) and it will again stop in the same distance. The important part is to understand that a bus under GVWR, even with a tow'd, will stop in the same distance as a non-towd bus provided there's sufficient reserved capacity with the brakes. This is why the criteria in the California Vehicle Code is stopping distance, rather than obligatory installation of service brakes. Brian had to use more of that "reserve capacity" which is why the pedal application (braking pressure) was higher. He stopped in the same distance because the brakes reserve capacity wasn't exceeded. An unbraked Tow'd acts like a guy pushing you forward while you're resisting against getting pushed over the cliff. Assuming that you're strong enough to "carry" this guy (the equivalent to not exceeding the brake capacity) if the guy hops on your back, you can backpedal away from the cliff with ease as nothing is working against your efforts. If Brian switched the weight of the Tow'd to braked axles, he'd get rid of the "guy pushing from behind" and only be required to expend the usual effort to stop the bus - which would happen in the usual distance. | ||
| Stan Rating: N/A |
Marc: What you said now is very clear. But you followed up the previous quote with this statement, and therein lies the confusion. "All else being equal, adding weight equivalent to the tow'd on the BRAKED AXLES by placing sandbags in the bays/cabin, would see the pressure guage dropping back to the original value." | ||
| Marc Bourget Rating: N/A |
Stan, Sorry, I wasn't more clear. If the tow'd's weight is added to the braked axles, less of the system's reserve capacity is being used and the brake pressure required to generate equal stopping decelleration would go back to the original amount Brian noted. Now that I explained further, do you agree that my earlier, inartfully drafted, statement was correct? | ||
| Stan Rating: N/A |
Marc: My poor old brain is having difficulty with what may be just convoluted terms. Now that you have added in the reserve capacity of the brakes it makes more sense. In order to use the reserve capacity of the brakes does it not require more air pressure applied to the brake cans? I just don't see a fixed amount of friction in the brake system stopping a heavier load. BTW I am not an automotive engineer. | ||
| Brian (Bigbusguy)
Rating: N/A |
Marc, I have no Idea what your saying your trying to use big words to prove some point that no one hare understands. One thing Im highly trained in moving large weight and stoping and know how added weight does to your stoping. Im may not type very fast or proof read every thing I post so I may give the apperance of some one stupid. Here is how it works. Most every ones bus here if not over built is under the GVW. So lets say adding a 6000 lb large SUV will put it under the GVW. A normal stop with out added brakes on the towed you can stop in the same distance with or with out a towed . Over load you bus buy 10000 lb in a normal stop you can still stop in the same distance. In both cases you will have to use more air to stop(Push a little harder on you brake valve) To stop in the same distance. In a panic stop bus at max GVW ether towed loaded on the roof or towing it will stop in the same distance or realy close if there is no wheel lock You could get more braking if the weight is in the bus not behind becouse it will take more to skid the wheels. Heres where you get safer. In a panic stop using all the air to where the wheel just about lock up. The bus will stop faster if the added weight stoped it self the bus will stop like it had 6000 lb less. If the 6000 lb had no brakes you will take longer to stop . Also if the road is wet your in a turn the added weight may push you in to a slide if it had no brakes. The only time you will see a longer stoping distance is when you realy need to panic stop if your towed had no brakes. And bounce off the car in front of you becouse you went even 1 foot longer. If its me, my neck hurts my back hurts I cant work I will take you for all I can . Im not saying you all need to go out a buy one just showing that you will stop longer with out one in a panic stop where you need to stop. You get The list of experts . But I know Im right And put this here for the record I will put My bus title up if you can prove me wrong. Do they have a test track the the Oregon Rally? Put some money on this. Engineer Brian 4905 | ||
| Marc Bourget Rating: N/A |
Brian Said: In a panic stop bus at max GVW ether towed loaded on the roof or towing it will stop in the same distance or realy close if there is no wheel lock You could get more braking if the weight is in the bus not behind becouse it will take more to skid the wheels. Brian, This is a Basic Science Post (BS to the uneducated and argumentative observer). What you say is basically correct, the only point I believe you fail to consider is whether or not there is any reserve braking capacity in your example. Until the reserve capacity is used up, what you say will happen is identical to what I tried to explain above. Otherwise, I feel you've restated what I said with different words. Once you use up the reserve braking capacity you will use more distance to stop because that is simply the how the physics is defined or how the braking system "works". Were both saying heat is hot but I'm pointing out that things don't catch fire till you exceed the heat they can tolerate ( like the brake reserve) All your real world experiences are true, but you're ignoring the distinction that I'm trying to make. The purpose I make the distinction is to educate those who are unaware of the dynamics so as to help them avoid what your experiences have taught you through practice in real life. Many converters never had to deal with your weight "issues". You (probably) have never had to put these issues in writing or agreed on definitions and terms. Check out what I've said above and in prior posts and tell me where my terms either don't match or are inconsistent with your terms and then I can approach your point more precisely. Marc | ||
| John that newguy Rating: N/A |
To an observer, both you and Brian are stating the same facts. It would have been easier on fragile minds (like mine), to simply say that the momentum of an un-braked towed vehicle will greatly extend the stopping distance over what it would be, if the vehicle's weight were inside the towed vehicle, instead. (anyone got a few aspirins?) | ||
| Brian (Bigbusguy)
Rating: N/A |
Marc, If you know any thing about driving a large bus or truck not just all from what you read or have heard from so called experts trying not to pay claims in insurance claims. For max a panic stop you use all the braking you have just up to the point of wheel lock and any braking reserve you have left you dont ever use it and has nothing to do with stoping distance if you do use it you will have wheel lock up and your stoping distance will be longer and you then lose control (see vid of bus crash). I know you dont want to say any thing that is not one way or the other way. use a lot of lawer type talk. Answer this: A bus with a towed with brakes will stop quicker and shorter during a panic stop. YES OR NO The word panic stop used in the above question . Using all avalble braking up to a wheel lock. A good driver will not use the reserve braking capacity that would only lead to wheel lock and not decrease the stoping distance. If you answer is NO explane in simple words every one can understand how and why. Also I would fly with a pilot that has real life experance not one that just read a book on how to fly. Brian 4905 uneducated and argumentative observer | ||
| Marc Bourget Rating: N/A |
Brian, You were not the uneducated or arumentative observer I was referring to. This is the second time you've chosen to take my comments personally. Why would I say you were basically correct, that we're both on the "same page" and then insult you at the same time? If what you really want is an argument, I can suggest a name. In response to your question. Yes, if, like you said, the brakes are operated at maximum (just short of lockup). However, if the conditions are the same, except the tow'd is not braked, then the answer is no. But you already said as much previously. The "grey area" is what happens when the stop is at less than maximum braking. I should have stayed away from that point. A pilot who has just read a book on how to fly technically is not a pilot as he's not allowed to fly. I don't have JayJay's or FF's experience but I'm Commercial, Instrument- Airplane, Commercial Rotorcraft. I have piloted 35 different types of aircraft, single and multi-engined and 3 helo's. I'm also have possessed a Class A license and shuttled a set of doubles regularly between Northern and Southern California when I was in college, so I know weight and commercial vehicles, too, but not as well as you! Hope we're in agreement, now. | ||
| Brian (Bigbusguy)
Rating: N/A |
Marc, Yes Im glad you agree with me now. Brian 4905 Dash-9 pilot | ||
| RJ Long (Rjlong)
Rating: N/A |
Brian - Don't really know why you're arguing with Marc - you're both saying the same thing! At least, that's how it comes across to me. . . I was an Operation Lifesaver instructor back in my Driver Training days, so I understand what you deal with daily - at least in my mind, as I've never had the opportunity to ride shotgun with a fellow like yourself to experience it first hand. (Would like to tho. . . hint, hint!!) More on your occupation in a moment. A point I'd like to share as an illustration is something that happened several years ago, when my family took an extended vacation in our vehicle, pulling a travel trailer with electric brakes. Somewhere between Cheyenne WY and Rapid City SD, the brake controller failed. Yup, that made a BIG difference in braking, and it can be stated two ways: #1: Using approximately the same pedal pressure as before, the stopping distance DID increase. #2: To stop in the same distance as before, it required a LOT more pedal pressure. Remember, this was the same vehicle/trailer combo, just the difference between using brakes on all three axles (tow vehicle + trailer) vs. just two axles (tow vehicle only). Now, I can understand that a coach like your 4905, towing a lightweight vehicle like an original VW Bug, may not feel significantly different with normal braking, or even hard braking, up to, but not including a panic stop. (Panic stops are a different ballgame - that's when all he** brakes loose (pun intended) and the proverbial change of underwear is needed!!) But put a full-sized pick-up, or a Suburban on the back, and you will feel it every time you touch the brake treadle. Especially under heavy braking. Which is what you've been saying, right? Now, add a supplemental braking system to the Suburban, especially a proportioning one, and the 'Burb now starts doing it's share of the work, so you don't put the extra load on the coach's brakes - which also means you don't have to modulate them nearly as much, and your stopping distance returns to approximately the same distance as the coach w/out the toad. Agreed? As I've read thru this entire thread, that's the message I've been getting, and I certainly think both you and Marc have been saying the same thing. Now, a question related to your occupation: Two configurations, both at 60 mph: 1> Six power units, 100 cars loaded with coal. 2> Six power units, 50 cars loaded with coal behind the power units, 50 empty piggy-back cars coupled to the coal hoppers. You come around a curve to discover an 18-wheeler stalled at a grade crossing, trailer only on the right-of-way, driver WAY off to the side where he won't get hurt waving frantically. You now "stand on the brakes" (so to speak), but just shy of flat-spotting all the wheels. I realize #1 will probably take longer to come to a full stop (about 1.5 - 2.0 mi. from 60 mph, right?), but my question is this: What will be the difference in the cab be for you between #1 and #2? (Forget the demolished trailer, I'm just referring to what you'll experience under these stopping conditions.) Do you have to modulate the brakes differently, and if so, how so? Thanks for sharing, Brian.  RJ PD4106-2784 Fresno CA | ||
| RJ Long (Rjlong)
Rating: N/A |
In the time it took me to compose my commentary, I see that Marc & Brian have figured out they've been saying the same thing. That's a good thing!! Was beginning to remind me of "Who's On First" Brian, would still appreciate your comments on my questions. RJ | ||
| Brian (Bigbusguy)
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RJ, Its all about TOB (tons per operative brake) 1> Would have about 130 TOB 2> Would have about 82 TOB So with #1 you would have to brake earler to stop at the same place. So you was right about that. If there was time 9 out of 10 time you just put it in emergeancy and modulate the brakes on the engines. In stoping both 1 or 2 quickly with out emergeancy you do about the same thing. What changes is how long the train is how soon you make more brake valve movement . There is only so much I can say about it with out getting in trouble. Something to do with homeland security. One way to put it .Is tow you bus with your toad no brakes on your bus. Get it up to 45 mph and now you know your going to stop in 2 miles at 1 1/2 miles from your stop you get off the throttle about 1 mile from your stop down shift about 1/2 mile from your stop down shift some more and use your emergancy brake push it in about 1/4 of the way at about 1/3 of a mile from your stop push in the E brake about 3 more clicks at about few hunderd feet to go give the E brake 3 more clicks and just as you comming to a stop step on the brake pedel and stop within a foot or so of where you wanted. The key is to time all of that not to stop too soon or too far if your past the red light your fired you go home right there after you pee the the bottle. Now some truck is around the corner on the tracks. You do all of what you would do to stop at a light but only quicker and use more of the E brake. Or just put it in emergancy and hang on. There is a lot more to it then that but that should give you some Idea what fun stoping 15000 tons or more that is 1 mile or more long. Brian 4905 | ||
| Henry R. Bergman, Jr. (Henryofcj)
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Bob and John may have it wrong. The proper spelling of California may be "Commiefornia". He he he. | ||
| RJ Long (Rjlong)
Rating: N/A |
No, Henry, you've got it slightly wrong - it's now spelled "Californication". |