Unfortunately you were given some bad info. From the 1960's into the 1990's the permitted gross weight of railcars was 263k (131 tons) which works out to 100 tons of payload and 31 tons of tare weight. Grain cars of capacities between 4427 and 4750cuft were designed to these standards. In the early 1990's the gross weight was raised to 286k (143 tons) which works out to 110 tons of payload and 33 tons of tare weight (exact figures vary from car to car). Grain cars with capacities between 5161 and 5400cuft are designed to this standard. When you look under the reporting mark and number, the "LD LMT" is the payload capacity in pounds, and "LT WT" is the tare weight. When you add the two numbers together, they should equal either 263,000 or 286,000. Some older cars follow some older and lower weight standards, such as the "70 ton" boxcar which was designed for 70 tons of payload and about 35 tons of tare. Those cars were built to a 210k standard.
This is a great explanation. This explains why Class-1 and Class-2 railroads in North America trade or sell off older locomotives of 20-plus years. The tractive effort, fuel costs, and horsepower (only needed to get a train moving) increases the number of locomotives needed. Railroads don't buy new power like we buy cars/trucks. They don't buy them because its the newest year model (lol we are silly consumers then). And the railroads usually don't buy older models (like used cars). That's why so many shortlines love them.
I used to work at CN rail, currently at VIA Rail. The territory I operated on in northern ontario required a minimum of 0.6 htp to operate over. Our steepest grad was 0.5%. That being said, a 0.6 hpt train would struggle over those grades. Getting a "run" at it was always favorable.
As a retired professor of chemistry I applaud your project. Since you know the time it took for each train to reach a given velocity, you can use kinematics to find the relative accelerations (v = v(0) + a*t), since you have a good estimate of the car weights you can use that to calculate the force (F = m * a), and from there you can calculate the Work (W = F * d) and compare them. Finally, since Power = W / t, you can compare the results to the horse power of the engines. Note that if there were no friction and air resistance, you could use a tiny locomotive to pull any train... it would just take a long time to get to speed. BUT, when you go uphill there is a steady deceleration due to gravity.... SO it takes a lot of force to go uphill. You can calculate that using trig functions. Good job, good start to becoming a scientist or engineer. :)
you are overthinking it. It's much simpler then that. You just take the heaviest % grade on the line to be run. From there that will set how much Horse Power per Ton. (HPT) Some grades require 2.5 HPT. Other lines only require 1 HPT. I've been railroading for a very long time now ;)
@@christianblankenship7683 - You are exactly right... I am trying to show him the FUN of overthinking it. I want to encourage him to learn how to use fundamental formulas of physics to derive the answer from scratch... Of course in practice one will use rules of thumb based on experience. If he grows up to be a railroader it will be good to have an understanding of how/why the rules of thumb work. If he grows up to be a scientist then he can help put together rules of thumb for other people. If he grows up to be a politician then we will all have failed him. *grin*
After working on the railroad with the EMD ST70AH, GE ET44AH, and ES44AH I can say only 2 Locomotives will pull that weight on flat ground and you may need one more if pulling hills in mountainous terrain. We pulled 229 cars one night where 85 of them where loaded rock hoppers and 30 where loaded scrap hoppers and gondolas. So I say around 2 or 3 will do it
The BHP-Billiton iron ore trains in Australia’s Pilbara region gross over 40,000 tonnes and the track has 40 tonne axle loadings (160 tonnes/ 176 US tons per ore car). Most of it is flat or downgrade running to the port so they can get away with 4 x SD70ACe (2 at the head end and 2 in the middle with Locotrol remote control). I think the ruling loaded grade is only 1% or not much more.
Westbound grain trains coming through Flagstaff will typically be 4X3X2 configuration, and usually are very long consists. 9 locomotives to get it up and over the hill from Winslow to Seligman to is the norm.
@@-HDK- if that train isn’t heading toward Tehachapi (to Northern California) and instead will head down Cajon Pass I’m guessing those added units are used for braking.
Your equation is good. On a flat surface, with no curves and no wind your train will move. The equation gets complicated the more variables you add. The steeper the grade the more horsepower per tonne you will need. Similarly add wind, more horsepower per tonne. And again, curves will add to the equation. Your train might be 1.6 kilometres or 1 mile long. But that 1.6 kilometre may be over one or more curves. The steeper the curve the greater will be wheel drop on the curve. Then wind. If your train is a single level container train this is good. Let’s make it double stacked. That is one container on top of another container. The effect of wind loading is almost doubled.
In a RW situation, I'd add more locomotives just for the dynamic braking. Getting moving wouldn't bother me as much as the inability to stop that much weight.
Throw in a few more variables. You can't exceed 350,000 pounds of draw or you will start breaking knuckles. This means distributed power if you have to go beyond that. The top speed of the train makes a difference. Fastter = more hp. A coal or iron ore train doesn't need the speed of a Z container train. Ore trains in Minnesota are dispatched at 0.3 to 0.5 hp / ton, but held to 30 MPH max when loaded. This is compared to 2.5 to 3 hp / ton for a Z container train looking for 50 to 70 MPH with quick acceleration. As mentioned elsewhere grades and curves make a huge difference. Track and subgrade make a difference. Spongy roadbed requires much more horsepower than more firm roadbed. Still, very good work.
Yes, I was the one driving the train, we broke a ton of knuckles, we didint want to put DPUs on as we wanted raw HPT. The train also had a TON of slack, I think the reason the 2 and 1 unit trains had so much trouble is that I did about 1 notch every 2 minutes, breaking knuckles was defiantly a big issue here.
@@johnchambers2996 couplers shearing? I thought all modern locomotives are equally adept at pushing and pulling. Believe it or not I didn't know electric motors on the drive wheels moved the trains along the tracks until I in my late twenties.
@@peterhart1966 Diesel-electric; the diesel engine turns an electric generator that provides electricity to the traction motors on each truck. Coupler shearing is a problem with long trains where the number of cars being pulled causes the tension to get so great that the couplers can shear at the upper end. They found that out back in the days of stream where some of the locomotives were getting so powerful that they had to be used to push the loads to put the couplers in compression instead of tension. I think that that's probably why on long trains they hook diesel-electric locomotives in the middle or end of the train; a push-pull operation.
The posting of important information on the screen at 1/10000000000000000 of a second was just a great touch. Great job guys of what your trying to convey...
not only did he address grades in this video, the company that gave him that formula also involved grades in making the formula so i don't really know what your trying to get at.
Totally makes common sense! I see now how it could be equivalent between each of the hp of the engines and how much it takes of different kinds of freight cars
Really good for a science project! Good to see younger generation taking their interests and using them, and utilizing the scientific method... I hope you'll explore taking some physics classes in the future... and just be sure to use trains there too... I did for both my University Physics I and University Physics II final projects. As others have noted, there's many many variables to explore, and many other things to research and consider (i.e, GRL, TE vs HP, etc)
Well we moved 21k metric tonne iron ore trains with one SD70 to and from one of our iron ore mines, over generally flat gradients.... Normally we have 4 sd70’s pulling 42/43 thousand tonne iron ore trains over the rest of the network which has much steeper grades...
A fully loaded car can weigh up to 143 tons and still run on the system without restrictions. Some things to think about is the the drawbar weight we would not have a 174 cars weighing 143 tons each and run it conventional that would exceed drawbar tonnage so it would need to be in a DP configuration ( distributed power ) . Some trains operate on some territories with as little as 0.2 HPT while others require much more due to mountain grade or just priority. A high priority train may be as much as 5.0 HPT or even more so that it can climb grades at track speed. Most trains in average are 7k to 8k in length in the last couple years BNSF had been running trains as long as 16k. An average coal train is 19k tons in weight but BNSF is experimenting with trains as heavy as 30k to 40k tons. To make make these mega trains work you have lead consist and mid consist and then DP units to make it work. Keep experimenting and I hope the information I gave will help and spark new ideas and scenarios for you
Very interesting, great graphics. But in unit trains of grain the car weight is 286,000 lbs or 143 tons. Other factors beside the grade is the curvature of the track, how much the track deflects under the weight of the wheels or as some people call it pumping. As a note concrete ties save 2 to 3 percent fuel over wood as they do not bounce(deflect) as much under the weight. In Canada the biggest railway/railroad, CN Rail has one big advantage, It was built about 1905 and by then they had dynamite as most US railroads only had blasting power, so the grades and curvature are less. Max grade Toronto to Vancouver is 0.5% westbound and 0.7% eastbound so less than 1%. CN Rail uses 3 locomotives on 200 loads of grain, although DPU is used it is not necessary
I work for a class 1, the rule of thumb is 1hp per ton per % of grade. My territory is in the plains, ruling grades of 0.6 so trains are run at 0.6hpt. However the company will push trains with all AC power to 0.4hpt. In the mountains they add power. If the ruling grade is 1.4 they add power to get the train to 1.4hpt. Also gross weight of a loaded grain car is 135ton.
It's like a 2 engine scraper works, only on a much bigger scale. PUSH-PULL. Definitely it is an advantage having to climb steep grades.There are so many different hook ups, depending on how many cars are handled.
I saw a Northwestern lash up with 240 coal cars and 24 engines moving northbound through the Lake Forest Illinois area. 12 head end 6 in middle 6 pushing early 70's date All EMD of mixed ages from my memory. I heard it was a test run for the radio control equipment.
Locomotive horsepower really shouldn't be used as we are talking strictly the horsepower coming out of the engine. Tractive effort is more accurate as it takes in consideration the weight of the locomotive. You could put a 10,000 horsepower engine in all those locomotives and I doubt you are going see much difference as any locomotives pulling force is dependent on weight. Even with the best wheel slip technology wheels will eventually slip, it's simple physics. Furthermore diesel locomotives lose about half their tractive effort after 15 MPH and it only goes down from there which is why they go so slow up even small grades at low speeds. On flat land even a lone SD40-2 can pull a 10,000 ton train. Your calculations do seem correct as we frequently have 18,000 ton grain trains coming through Denver. Four locomotives is the minimum they use with no grades. They need another 2 pushing once it starts going up a grade.
Thanks for the video. Most of a train's HP is used to pull all that weight up grades. Trains roll very efficiently on level track, but when it goes up hill it has to lift up all that weight against the force of gravity which takes way, way more energy than rolling on level track.
Keep in mind that when it comes to grades, anything over 2% is hard for trains to pull or handle up or down grade. Vehicles we own including most semi-trucks can handle grades of 5% or greater. Yeah, think about that the next time you're driving and you are handling a hill at 60 mph!
You should order this book: 'Fuel Saving Techniques for Railroads' All of the discussions about hp/ton, the effects of grade, tractive effort, etc; are covered in depth in that book.
It's a pretty cool experiment. It would be interesting to experiment with DPU configurations spreading the locomotives throughout the train, provided the simulator is sophisticated enough to take traction and dynamics into account.
Bro this is train math,.... TEACHER: if you have 5 SD70ACe and 5 GEVOS take 2 GEVOS and 2 ACES away how many gevo and aces do you have combined comment below if you have the answer....also great video
Much of your commentary is incorrect. First off, it does not “take” 1hp to move 1 ton. Many of the grain trains and coal trains coming through my region are doing so with .75 to .8 hp per ton, and traveling fine. What gets a train moving is not HP, but tractive effort. Oh can have all the hp on earth, but if you cannot adequately apply it to the rail, your train is not going anywhere. HP only enters the picture to the extent that it can be used at the rail head. One example I’ll give you was a test conducted by the CB&Q (Burlington Route) in the late 40’s, where they sought to see what their fancy new F3’s could do. A SINGLE F3A (1500 hp on 4 axels) was coupled to 10,000 tons. Remember also, this was in the days of brass friction bearings on all rolling stock. While they never achieved more than 4mph, this F3A got this 10,000 tons of freight moving. This was .15 hp per ton. With no modern wheel slip control. HP only becomes significant once things are moving. As long as you have enough traction to get the train started, it’s HP that keeps it going and makes it able to accelerate. A modern SD-90 AcE with something like 190,000lbs of starting tractive effort should, theoretically, be able to start 20,000+ tons on level track, given that an F3 with 1/3 the tractive effort and 1/3 the hp could move 10,000 from a stand still. Now DOING anything with it beyond that is another problem entirely. Then there is your commentary regarding the weight of loaded grain cars. This is also stated incorrectly. On the side of most cars are several things. One says LT WT, this is the light weight, or empty weight of the car. Next to it is usually LD LMT, or Load Limit. This is the capacity of the car for cargo. I cannot post a picture here, but in the example of a 6300 cu ft hopper I just looked up these show LT WT 61000 LD LMT 225000 This car weighs 61000 lbs empty, or 30.5 tons, and has a carrying capacity of 225000 lbs, or 112.5 tons. The maximum loaded weight of this car, in typical service, would be 143 tons, not the 115 tons you mentioned. You are referring to the load limit weight, not the gross weight of the loaded car. A typical 110-115 car loaded grain train, often with 3 units totaling 13,200 hp, weighs in at around 16,000 tons. If we assume 3 typical 4400 hp GE’s on this train, we get a scheduled train moving with .825 hp per ton.
Your assumption is completely false.you equate horse power with tractive effort. You can have 5 ES44s all with the same horse power (obviously) yet all with different max tractive effort AND, I forgot to mention, rail adhesion. The different tractive effort comes from the programming in the computer that the railroad has set or ordered and from the weight of the locomotive. Which can vary s much as 80,000 lbs. Obviously, the heavier the locomotive, the more tractive effort can be applied to the rail before you get wheel slip. I personally have operated a train in excess of 18,000 tons with only 2 SD70MAC's on relatively flat yet undulating terrain and was able to get the train to 60 mph in under 2 miles. Not exactly burning up the rails but an impressive accomplishment considering the weight.
The question is not complete, I will also need to know the % of grade, how long the longest hill is and at what alitude above see level that grad is located. One additional bit of information needed is the radius of the turns on that grade because all horsepower cannot be applied in one location in the consist or your rail cars will clothesline, especially if there's a dip in the track on a turn. Speaking of turns are any of them super elevated ?
some what, to start the train 100%, tractive effort is a huge part, but as you get up to track speed you'll need power to keep you going, for example if you were to note every train on a mountain route, say Cajon you will noticed if you use just the tractive effort formula you will have very under power trains A standard ES44AC produces about 180,000 lbs of tractive effort at start multiply say three you have 540000 lbs or 270 tons of tractive effort, that won't move your standard size train of 100 grain cars each weighing up to 286,000 lbs or 143 tons up a 0.25% rolling grade. Now the AC traction of the ES44AC will help you some but in the end you'll stall. Now I'm using a very heavy grade for my example going across the great plains yes you could make do, but as soon you get to any "good" grade you'll be delaying the trains behind you.
@@RyanHatterer-Ryanns999 That’s true. Probably why lots of trains that are particularly heavy or going over grades have SD70ACE/AHs, because they have higher tractive effort and pull harder than most other locomotives
@@paulspomer16 They actually don't produce as much tractive effort as you think. What happens is when the rail conditions are not as good say rain or snow for example the computer will for GE AC units blow a small amount of air onto the rail in front of axle one and control how much sand is use. yes they weigh more up to 432,000 lbs (216 tons) from 420,000 lbs but the amount of tractive effort compare to a standard SD70ACe in your case is not that much maybe 15,000 lbs at most. The AH system (I'm more friendlier with the GE system then EMD) Really works well in poor rail conditions and at low speed in heavy haul and mountain grades, which comes back to my point where tractive effort is really important to start the train at low speed not so much to keep things moving. When you get up to say 10 to 20 Mph the tractive effort curve drops greatly, but you'll noticed horsepower stays pretty well level until you get up to the top speed of the train say 55 to 65, then it'll start to drop because the traction motor is getting close to it's top RPM.
nice comment but only PARTLY true... yes tractive effort is important as it is needed to get the train moving... like with a hump engine set (a switch engine and let's say 2 heavily ballasted slugs)... while the HP is low (relatively speaking), there is enough tractive effort (weight on drivers) to get a long heavy cut of cars moving... but only at LOW SPEEDS... no speed records will be broken using this set of hump power... now the horsepower is important IF you want to move at higher speeds... horesepower is related to SPEED once the train is moving... think back to the 90s on the SP, they used 4 or more GP60s on their intermodal trains as every added engine increases horsepower which increases speed
Ive found out that any grade steeper than 1 in 40, requires the horsepower rating of each loco to be 8 times stronger than normal in order to climb the grade with ease
The outfit I work for would only use 2 engines for 150 grain or 150-200 car coal train from Roanoke to Norfolk! I'm guessing this video takes into account the Rocky mountains=steep grades. Still a great video.
Also, a double has 232 cars and 8 locomotives. 3 in front, 3 cut in in the middle and 2 on the rear. 32,000 tons. They handle surprisingly well, just have to plan your stop an extra mile ahead.
No matter how one figures how many locomotives are needed for a certain route, trains can still stall out. Photos and videos have been seen, of a stalled out train. One or more power units, are still needed. Yes, it costs money and time to use extra power, above what was figured in. But the major railroads do have extra stored power. If ya got it, use it. Sometimes, better safe than sorry.
tractive effort is more important than horsepower, Saying that horsepower is what is moving the heavy train alone is like saying you could haul a 20k t with 3 TGV power cars (rated at 9,400hp each). Google Krug Tales Tractive effort V Horsepower to get a better understanding
@@hobartsignalproductions3994 these are the dark days of PSR. So 2x3x1, or two 2x1 grain trains slapped together. Is the norm. If it only goes over a .9 grade hill at 13 mpg. Oh well. If it loses an engine and stalls. Oh well.
I see a lot of non railroad employees commenting on your video. And most of are wrong. Several months ago I had a lone GP15-1, A 135 ton FOUR AXLE switch engine, pull 115 loads 25miles from one yard to another. I never got above 15mph but that little sjmbitch got me to the next yard and didn't give up the ghost or overheat. By the way my railroad, U.P. usually assigned 3 A.C. LOCOMOTIVES to our 110 car grain trains. 2 pulling and one DPU on the rear.
For what it's worth there are many variables in moving trains. I've run many trains with less than 1 HPT. Certain high priority trains are required 2+3 HPT to maintain schedule.
Speaking from experience. In western Canada cn rail routinely runs trains at 0.5 hpt. Not uncommon to see 3 engines (2 headend and 1 on the tail) of 170 loads. Max grade 0.7%.
One Big Boy locomotive will move that amount of cars without crackin a sweat.Theres a video of The Mighty Challenger pulling 143 cars over Sherman Hill at 35 m.p.h !! .These old steamers ain't no joke .
I can see for uphill and down hill speeds but do all locomotives have to run all the time under power or can one or two be at idle while on flat terrain to reduce fuel costs?
Locomotives can be run at idle if there in the middle of back of the train. Crews can use DPU fencing so that the DP units run sepertly than the front units, but this is mostly used for cresting a summit of a hill where the lead units can be in dynamic brakes and the DPUs can still be running power. Personalty I just run the units all the same on flat ground and instead pf being at notch 5 or 6 to maintain speed, i might just have my units at notch 2 or 3 saving fuel in all the units.
These HP Rates are just a Number to simplify the Calculation. What really Counts is the Traction Effort your Locomotives can bring onto the Rails. An european electrical Loco with > 10000HP may be capable to move a Train at > 120mph but it will never be able to pull such enormous Loads. Simple because of the Fact that American Locomotives weights twice as much as the european Locos.
I've seen maybe a total of 3 or 4 locomotives hauling that length of train the combos I've seen growing up are the standard 2 in the front and 1 at the back or I've also seen 3 in the front and 1 at the back or just all 3 in the front and none at the back I have a channel here on TH-cam that shows some of these combos if you want to go look
this video was interesting and I enjoyed it, however I have a couple of questions and i don't know all the correct terms. How is the Horsepower requirements determined for a train going over the cajon pass or other steep grades and also how are the number of electric motor breaking axles determined for the down hill side? Does a simulator exist for running a loaded train over the cajon pass?
The hpt requirements are set for different routes example Tehachapi has a minimum of 2.3 but generally speaking you always want more than 2 hpt. The crew determines the length of the train and the tonnage and what percent grade there going down they can set whole locomotives to cut out the dynamic brakes or individual traction motors. Hope that helps. and yes the sim e used has the Seligman sub needles sub Mojave sub Bakersfield sub Cajon sub and the san Bernardino sub just look up run 8.
@@hobartsignalproductions3994 Thanks for the information I find this stuff interesting. years ago we lived in the Sierra foothills and i remember the trains leaving Rocklin for Truckee and it seems that the trains had more engines then I have finders to count them, again thanks for the info.
Pretty cool video, one thing you need to factor in is weather conditions. There’s a big difference starting out on wet rain than dry rail and pulling steep grades
@@BurlingtonNorthernProductions lol. Must suck having to wear a mask. Glad I graduated last year, I could not even think I could handle that, without federal minimum wage.
it's gonna take 8 locomotives 4 in front 2 in the middle and 2 on the end. of its raining then add 2 more locomotives.. if it's hot above 90* then add 2 more locomotives. the reason! there are too many locomotives sitting idle in a few yards around the country. you've got the resources use them less fuel burn
In reality, I believe the Engineer has the final say on the number of locomotives used. Scheduling or whoever uses a formula for the lashup, but the Engineer knows the route and all up and down grades and the tractive efforts involved. We will find that they may go with a 3 or 4 engine lashup and then add in one or more Distributed Power Units (DPU's) to account for strain at the knuckles. Great exercise! Very informative :)
Having had my “engineers card” for 22 years I’ve never been able to pick or lash up my own power (I wish) but with the way the railroads run now is straight money saving mode ... I’ve been told to run a 7000 ton freight train with one motor online and it takes an act of god to turn that 2nd loco online but it’s their RR .... they late 90s and early 2000s were a lot better .... give me 3-4 SD60s old school cabs and let me go !
Here's a railroad, rail fan question. A single locomotive is pulling 45 cars at 100 miles per hour. The train has traveled 79 miles straight at the 100 mile per hour speed. What was the name of the engineer?
what am I missing here ? what happened to Traction Effort ? just asking, as my old brain cells remember correctly, that use to be a guide in figuring things ?
@@Unsound_advice Only one. The leader would release air setting up the brakes on the cars and that would stop the train. It is all about the grade. 20,000 ton, 210 car grain train with 2 on the head three dp's and one on the rear will pull 1 percent grade. Not fast about 10mph. up hill.
INTERESTING --- I wonder what role the position of the locomotives would play in actually accelerating the train to 15 mph assuming 0% grade, same number of locomotives, same horsepower, and no wheel spin. Does having 3 locomotives up front, and say, 2 locomotives in the middle help vs having 5 locomotives up front? Apparently, a lot of trains are configured this way and so there must be an advantage.
The main difference is you'll be able to get the train moving a little better, because the DPU will be pushing at the same time you're lead is pulling compared to just everything up front. Also think about the fact you can only have some much pulling power on the head end due to the metal breaking point of the couplers.
Good vid. I'm assuming putting power on the back end shortens the time it takes to get the consist moving since a lot of slack action at startup is negated. All the major haulers have gone to that model or with mid units. Would be interesting to see the math on 2 headers and 2 pushers.
Overall, makes sense for 5 Locomotives to pull it. I thought you needed more than 10 locomotives. It's not about how long the train is, it's about how much power it can take to move it. A+. Also what is that simulator called?
What if a crew member didn’t get all the hand brakes off or you have units that aren’t loading properly. Then there’s the sanders. Are they working? Seems like less employees means less things work as in a perfect world. Don’t forget about the weather and who is behind the throttle. I used to call engineers plastic stick jockeys.
There are other variables to consider it is not a simple pulling equation. Track physical condition, crossings and switches, curves and there radius, wind speed and direction, atmospheric conditions (weather), physical condition of the cars (wheel profile, bearing condition, load distribution), need to keep to a schedule ( speed, acceleration, stopping distance). Always have a small safety reserve on theoretical max power calculated. One loco down on power would tip the balance.. Recent example on video of a train stalling on Horseshoe pass because it only had one locomotive. The train stalled just as it entered the tightening curve above the camera position at the observation building. Theory could dictate one loco for the load, the track conditions (only 1 year old) and the hill but add the curves it was too much.
It takes almost no power to move any grain car except to overcome bearing friction. Famous strongman Charles Atlas proved that in the 1930s pulling a Broadway Limited observation car with a rope. The trick is how fast. Horsepower (foot-pounds per hour) is not tractive effort (pounds), and trains require more HP as train speeds increase (tractive effort x speed). Add a grade and the drawbar pull increases dramatically since you're not just overcoming rolling resistance but actually lifting the train up a ramp. Instead of relying on someone's video game, a college course in Newtonian physics would be a better place to start.
on flat level ground (or at least mostly level) 1 locomotive can move 174 loaded grain cars. you see this in the real world all the time for those that sit at the crossing and count the cars. if you really want to test this. then how about doing the experiment again but with more than 6 locos. like a ridiculous number like 10 or 20 locos. what happens then?
Unfortunately you were given some bad info. From the 1960's into the 1990's the permitted gross weight of railcars was 263k (131 tons) which works out to 100 tons of payload and 31 tons of tare weight. Grain cars of capacities between 4427 and 4750cuft were designed to these standards. In the early 1990's the gross weight was raised to 286k (143 tons) which works out to 110 tons of payload and 33 tons of tare weight (exact figures vary from car to car). Grain cars with capacities between 5161 and 5400cuft are designed to this standard. When you look under the reporting mark and number, the "LD LMT" is the payload capacity in pounds, and "LT WT" is the tare weight. When you add the two numbers together, they should equal either 263,000 or 286,000. Some older cars follow some older and lower weight standards, such as the "70 ton" boxcar which was designed for 70 tons of payload and about 35 tons of tare. Those cars were built to a 210k standard.
This is a great explanation. This explains why Class-1 and Class-2 railroads in North America trade or sell off older locomotives of 20-plus years. The tractive effort, fuel costs, and horsepower (only needed to get a train moving) increases the number of locomotives needed. Railroads don't buy new power like we buy cars/trucks. They don't buy them because its the newest year model (lol we are silly consumers then). And the railroads usually don't buy older models (like used cars). That's why so many shortlines love them.
I used to work at CN rail, currently at VIA Rail. The territory I operated on in northern ontario required a minimum of 0.6 htp to operate over. Our steepest grad was 0.5%. That being said, a 0.6 hpt train would struggle over those grades. Getting a "run" at it was always favorable.
Interesting. 0.5% might sound little, but only if you compare it to roads, or hauling passengers, preferably lightweight ones.
As a retired professor of chemistry I applaud your project. Since you know the time it took for each train to reach a given velocity, you can use kinematics to find the relative accelerations (v = v(0) + a*t), since you have a good estimate of the car weights you can use that to calculate the force (F = m * a), and from there you can calculate the Work (W = F * d) and compare them. Finally, since Power = W / t, you can compare the results to the horse power of the engines. Note that if there were no friction and air resistance, you could use a tiny locomotive to pull any train... it would just take a long time to get to speed. BUT, when you go uphill there is a steady deceleration due to gravity.... SO it takes a lot of force to go uphill. You can calculate that using trig functions. Good job, good start to becoming a scientist or engineer. :)
Thank you!!
I am an 8th grade science honors student this means a lot. Thanks again!!
you are overthinking it. It's much simpler then that. You just take the heaviest % grade on the line to be run. From there that will set how much Horse Power per Ton. (HPT) Some grades require 2.5 HPT. Other lines only require 1 HPT. I've been railroading for a very long time now ;)
@@christianblankenship7683 - You are exactly right... I am trying to show him the FUN of overthinking it. I want to encourage him to learn how to use fundamental formulas of physics to derive the answer from scratch... Of course in practice one will use rules of thumb based on experience. If he grows up to be a railroader it will be good to have an understanding of how/why the rules of thumb work. If he grows up to be a scientist then he can help put together rules of thumb for other people. If he grows up to be a politician then we will all have failed him. *grin*
Don't forget you tool it will also take a loooooong time to stop!🤣
After working on the railroad with the EMD ST70AH, GE ET44AH, and ES44AH I can say only 2 Locomotives will pull that weight on flat ground and you may need one more if pulling hills in mountainous terrain. We pulled 229 cars one night where 85 of them where loaded rock hoppers and 30 where loaded scrap hoppers and gondolas. So I say around 2 or 3 will do it
Dang but we went over tehachipi it sounds like you orked for CSX because we dont have as44ahs eve only got dc acs and c4s
CN shifts 220 cars with 3 units 1x1x1
The BHP-Billiton iron ore trains in Australia’s Pilbara region gross over 40,000 tonnes and the track has 40 tonne axle loadings (160 tonnes/ 176 US tons per ore car). Most of it is flat or downgrade running to the port so they can get away with 4 x SD70ACe (2 at the head end and 2 in the middle with Locotrol remote control). I think the ruling loaded grade is only 1% or not much more.
Westbound grain trains coming through Flagstaff will typically be 4X3X2 configuration, and usually are very long consists. 9 locomotives to get it up and over the hill from Winslow to Seligman to is the norm.
Of which 7 are usually running. The 3 mids aren't really needed till Tehachapi, their main reason. Same train can make it with 5 or 6.
Ive seen that!
There usually 110-115 cars
@@-HDK- if that train isn’t heading toward Tehachapi (to Northern California) and instead will head down Cajon Pass I’m guessing those added units are used for braking.
5 locomotives are about right 3 in the front 2 in the back. To keep from popping the knuckle
How do you know we didint?
Your equation is good. On a flat surface, with no curves and no wind your train will move. The equation gets complicated the more variables you add. The steeper the grade the more horsepower per tonne you will need. Similarly add wind, more horsepower per tonne. And again, curves will add to the equation. Your train might be 1.6 kilometres or 1 mile long. But that 1.6 kilometre may be over one or more curves. The steeper the curve the greater will be wheel drop on the curve. Then wind. If your train is a single level container train this is good. Let’s make it double stacked. That is one container on top of another container. The effect of wind loading is almost doubled.
Thank you! This is my science project for this year (I'm in 8th grade) I do plan to do another project going up grades. Thank you for your help!
In a RW situation, I'd add more locomotives just for the dynamic braking.
Getting moving wouldn't bother me as much as the inability to stop that much weight.
What's a RW...? Rail Weight maybe?
@@crsrdash-840b5 Real World
@@MichaelClark-uw7ex lol...now I feel old
Throw in a few more variables.
You can't exceed 350,000 pounds of draw or you will start breaking knuckles. This means distributed power if you have to go beyond that.
The top speed of the train makes a difference. Fastter = more hp. A coal or iron ore train doesn't need the speed of a Z container train. Ore trains in Minnesota are dispatched at 0.3 to 0.5 hp / ton, but held to 30 MPH max when loaded. This is compared to 2.5 to 3 hp / ton for a Z container train looking for 50 to 70 MPH with quick acceleration.
As mentioned elsewhere grades and curves make a huge difference.
Track and subgrade make a difference. Spongy roadbed requires much more horsepower than more firm roadbed.
Still, very good work.
Yes, I was the one driving the train, we broke a ton of knuckles, we didint want to put DPUs on as we wanted raw HPT. The train also had a TON of slack, I think the reason the 2 and 1 unit trains had so much trouble is that I did about 1 notch every 2 minutes, breaking knuckles was defiantly a big issue here.
Left out how many are needed to control this consents when braking on a steep grade and bring it to a full stop.
Another thing is the couplers which is why some locomotives are used as pushers to keep the couplers from shearing.
@@johnchambers2996 couplers shearing? I thought all modern locomotives are equally adept at pushing and pulling. Believe it or not I didn't know electric motors on the drive wheels moved the trains along the tracks until I in my late twenties.
@@peterhart1966 Diesel-electric; the diesel engine turns an electric generator that provides electricity to the traction motors on each truck. Coupler shearing is a problem with long trains where the number of cars being pulled causes the tension to get so great that the couplers can shear at the upper end. They found that out back in the days of stream where some of the locomotives were getting so powerful that they had to be used to push the loads to put the couplers in compression instead of tension. I think that that's probably why on long trains they hook diesel-electric locomotives in the middle or end of the train; a push-pull operation.
@@johnchambers2996 5700 trailing tons on the scenic sub
The posting of important information on the screen at 1/10000000000000000 of a second was just a great touch. Great job guys of what your trying to convey...
Just today on the radio, I heard a 179 car loaded grain train with five engines leaving to go north out of Atlanta on the W&A sub.
l worked for bnsf, the grade effects the hp.per ton. some was 1hp. per ton others were 1and a half per ton.
Yeah, I'd like to see those 2-44s get over the Donner Pass.
not only did he address grades in this video, the company that gave him that formula also involved grades in making the formula so i don't really know what your trying to get at.
I work for CN and they’re happy with .4HPT. 2 locomotives for 28,000 tons. It sucks.
Half a hp is fine per ton
@@conrail666 it's fine, but I'm not a fan of doing 15 under track speed for half the subdivision
Totally makes common sense! I see now how it could be equivalent between each of the hp of the engines and how much it takes of different kinds of freight cars
Yup! Thank you!!
Instead of an A, even an A+, you got an E+
I've always wondered how railroad companies might be adding power to their trains, and as bonus, I can even find a cool simulator here!
Really good for a science project! Good to see younger generation taking their interests and using them, and utilizing the scientific method... I hope you'll explore taking some physics classes in the future... and just be sure to use trains there too... I did for both my University Physics I and University Physics II final projects. As others have noted, there's many many variables to explore, and many other things to research and consider (i.e, GRL, TE vs HP, etc)
Well we moved 21k metric tonne iron ore trains with one SD70 to and from one of our iron ore mines, over generally flat gradients.... Normally we have 4 sd70’s pulling 42/43 thousand tonne iron ore trains over the rest of the network which has much steeper grades...
A fully loaded car can weigh up to 143 tons and still run on the system without restrictions. Some things to think about is the the drawbar weight we would not have a 174 cars weighing 143 tons each and run it conventional that would exceed drawbar tonnage so it would need to be in a DP configuration ( distributed power ) . Some trains operate on some territories with as little as 0.2 HPT while others require much more due to mountain grade or just priority. A high priority train may be as much as 5.0 HPT or even more so that it can climb grades at track speed. Most trains in average are 7k to 8k in length in the last couple years BNSF had been running trains as long as 16k. An average coal train is 19k tons in weight but BNSF is experimenting with trains as heavy as 30k to 40k tons. To make make these mega trains work you have lead consist and mid consist and then DP units to make it work.
Keep experimenting and I hope the information I gave will help and spark new ideas and scenarios for you
Very interesting, great graphics. But in unit trains of grain the car weight is 286,000 lbs or 143 tons. Other factors beside the grade is the curvature of the track, how much the track deflects under the weight of the wheels or as some people call it pumping. As a note concrete ties save 2 to 3 percent fuel over wood as they do not bounce(deflect) as much under the weight. In Canada the biggest railway/railroad, CN Rail has one big advantage, It was built about 1905 and by then they had dynamite as most US railroads only had blasting power, so the grades and curvature are less. Max grade Toronto to Vancouver is 0.5% westbound and 0.7% eastbound so less than 1%. CN Rail uses 3 locomotives on 200 loads of grain, although DPU is used it is not necessary
Hey this is a very informative and interesting video about Freight Trains. Maybe the general public could use this as an education tool.
I work for a class 1, the rule of thumb is 1hp per ton per % of grade. My territory is in the plains, ruling grades of 0.6 so trains are run at 0.6hpt. However the company will push trains with all AC power to 0.4hpt. In the mountains they add power. If the ruling grade is 1.4 they add power to get the train to 1.4hpt. Also gross weight of a loaded grain car is 135ton.
Thank you! This is my 8th grade science project. I am still learning more about this stuff (because I am in 8th grade) but yeah lol
Thank you for showing us your video I learned something new today about locomotives and rolling stock that’s why I love trains and model trains!
Glad you enjoyed it
It's like a 2 engine scraper works, only on a much bigger scale. PUSH-PULL. Definitely it is an advantage having to climb steep grades.There are so many different hook ups, depending on how many cars are handled.
Nobody talks about the amount of punishing stress those knuckle couplers are dealing with on a daily basis...ouch!
The background music fire 🔥
What is the song
I saw a Northwestern lash up with 240 coal cars and 24 engines moving northbound through the Lake Forest Illinois area. 12 head end 6 in middle 6 pushing early 70's date All EMD of mixed ages from my memory. I heard it was a test run for the radio control equipment.
Or you could just slap a UP 4-8-4 on there🤣
Or even use 4 6,600 centennial locomotives
@@williesmalls8995 how about 3 GTELs?
4-8-8-4
Couple dd40's?
At first I thought this was a thinly veiled physics lesson. It might have been but it's really cool video.
try the formula of 2 pulling, 1 dpu in the middle, and 2 pushing dpu's.
Locomotive horsepower really shouldn't be used as we are talking strictly the horsepower coming out of the engine. Tractive effort is more accurate as it takes in consideration the weight of the locomotive. You could put a 10,000 horsepower engine in all those locomotives and I doubt you are going see much difference as any locomotives pulling force is dependent on weight. Even with the best wheel slip technology wheels will eventually slip, it's simple physics. Furthermore diesel locomotives lose about half their tractive effort after 15 MPH and it only goes down from there which is why they go so slow up even small grades at low speeds. On flat land even a lone SD40-2 can pull a 10,000 ton train. Your calculations do seem correct as we frequently have 18,000 ton grain trains coming through Denver. Four locomotives is the minimum they use with no grades. They need another 2 pushing once it starts going up a grade.
Thanks for the video. Most of a train's HP is used to pull all that weight up grades. Trains roll very efficiently on level track, but when it goes up hill it has to lift up all that weight against the force of gravity which takes way, way more energy than rolling on level track.
Keep in mind that when it comes to grades, anything over 2% is hard for trains to pull or handle up or down grade. Vehicles we own including most semi-trucks can handle grades of 5% or greater. Yeah, think about that the next time you're driving and you are handling a hill at 60 mph!
You should order this book:
'Fuel Saving Techniques for Railroads' All of the discussions about hp/ton, the effects of grade, tractive effort, etc; are covered in depth in that book.
It's a pretty cool experiment. It would be interesting to experiment with DPU configurations spreading the locomotives throughout the train, provided the simulator is sophisticated enough to take traction and dynamics into account.
Bro this is train math,.... TEACHER: if you have 5 SD70ACe and 5 GEVOS take 2 GEVOS and 2 ACES away how many gevo and aces do you have combined comment below if you have the answer....also great video
Much of your commentary is incorrect. First off, it does not “take” 1hp to move 1 ton. Many of the grain trains and coal trains coming through my region are doing so with .75 to .8 hp per ton, and traveling fine.
What gets a train moving is not HP, but tractive effort. Oh can have all the hp on earth, but if you cannot adequately apply it to the rail, your train is not going anywhere. HP only enters the picture to the extent that it can be used at the rail head.
One example I’ll give you was a test conducted by the CB&Q (Burlington Route) in the late 40’s, where they sought to see what their fancy new F3’s could do. A SINGLE F3A (1500 hp on 4 axels) was coupled to 10,000 tons. Remember also, this was in the days of brass friction bearings on all rolling stock.
While they never achieved more than 4mph, this F3A got this 10,000 tons of freight moving. This was .15 hp per ton. With no modern wheel slip control.
HP only becomes significant once things are moving. As long as you have enough traction to get the train started, it’s HP that keeps it going and makes it able to accelerate.
A modern SD-90 AcE with something like 190,000lbs of starting tractive effort should, theoretically, be able to start 20,000+ tons on level track, given that an F3 with 1/3 the tractive effort and 1/3 the hp could move 10,000 from a stand still. Now DOING anything with it beyond that is another problem entirely.
Then there is your commentary regarding the weight of loaded grain cars. This is also stated incorrectly.
On the side of most cars are several things. One says LT WT, this is the light weight, or empty weight of the car.
Next to it is usually LD LMT, or Load Limit. This is the capacity of the car for cargo. I cannot post a picture here, but in the example of a 6300 cu ft hopper I just looked up these show
LT WT 61000
LD LMT 225000
This car weighs 61000 lbs empty, or 30.5 tons, and has a carrying capacity of 225000 lbs, or 112.5 tons.
The maximum loaded weight of this car, in typical service, would be 143 tons, not the 115 tons you mentioned. You are referring to the load limit weight, not the gross weight of the loaded car. A typical 110-115 car loaded grain train, often with 3 units totaling 13,200 hp, weighs in at around 16,000 tons. If we assume 3 typical 4400 hp GE’s on this train, we get a scheduled train moving with .825 hp per ton.
Your assumption is completely false.you equate horse power with tractive effort. You can have 5 ES44s all with the same horse power (obviously) yet all with different max tractive effort AND, I forgot to mention, rail adhesion. The different tractive effort comes from the programming in the computer that the railroad has set or ordered and from the weight of the locomotive. Which can vary s much as 80,000 lbs. Obviously, the heavier the locomotive, the more tractive effort can be applied to the rail before you get wheel slip. I personally have operated a train in excess of 18,000 tons with only 2 SD70MAC's on relatively flat yet undulating terrain and was able to get the train to 60 mph in under 2 miles. Not exactly burning up the rails but an impressive accomplishment considering the weight.
CSX would say 2 gp-38's. Thats what they used on 150 cars back when i lived in tipp. But it stalled, and needed 2 pushers to get to the siding
The question is not complete, I will also need to know the % of grade, how long the longest hill is and at what alitude above see level that grad is located. One additional bit of information needed is the radius of the turns on that grade because all horsepower cannot be applied in one location in the consist or your rail cars will clothesline, especially if there's a dip in the track on a turn. Speaking of turns are any of them super elevated ?
The fact you took the time out of your day to make this interesting video
Huge respect for you
Thanks man!!
Np
Wow, very informative. I think there’s more main line locos to
Norfolk Southern math:
If I rebuild 100 locomotives and retire 700, how many GEVO’s would I have?
I gathered all of them.
The horsepower isn’t what matters dude... it’s the tractive effort that’s important
Yeah lol, sorry about that I am an 8th grade student this stuff is hard lol.
some what, to start the train 100%, tractive effort is a huge part, but as you get up to track speed you'll need power to keep you going, for example if you were to note every train on a mountain route, say Cajon you will noticed if you use just the tractive effort formula you will have very under power trains A standard ES44AC produces about 180,000 lbs of tractive effort at start multiply say three you have 540000 lbs or 270 tons of tractive effort, that won't move your standard size train of 100 grain cars each weighing up to 286,000 lbs or 143 tons up a 0.25% rolling grade. Now the AC traction of the ES44AC will help you some but in the end you'll stall. Now I'm using a very heavy grade for my example going across the great plains yes you could make do, but as soon you get to any "good" grade you'll be delaying the trains behind you.
@@RyanHatterer-Ryanns999 That’s true. Probably why lots of trains that are particularly heavy or going over grades have SD70ACE/AHs, because they have higher tractive effort and pull harder than most other locomotives
@@paulspomer16 They actually don't produce as much tractive effort as you think. What happens is when the rail conditions are not as good say rain or snow for example the computer will for GE AC units blow a small amount of air onto the rail in front of axle one and control how much sand is use. yes they weigh more up to 432,000 lbs (216 tons) from 420,000 lbs but the amount of tractive effort compare to a standard SD70ACe in your case is not that much maybe 15,000 lbs at most. The AH system (I'm more friendlier with the GE system then EMD) Really works well in poor rail conditions and at low speed in heavy haul and mountain grades, which comes back to my point where tractive effort is really important to start the train at low speed not so much to keep things moving. When you get up to say 10 to 20 Mph the tractive effort curve drops greatly, but you'll noticed horsepower stays pretty well level until you get up to the top speed of the train say 55 to 65, then it'll start to drop because the traction motor is getting close to it's top RPM.
nice comment but only PARTLY true... yes tractive effort is important as it is needed to get the train moving... like with a hump engine set (a switch engine and let's say 2 heavily ballasted slugs)... while the HP is low (relatively speaking), there is enough tractive effort (weight on drivers) to get a long heavy cut of cars moving... but only at LOW SPEEDS... no speed records will be broken using this set of hump power... now the horsepower is important IF you want to move at higher speeds... horesepower is related to SPEED once the train is moving... think back to the 90s on the SP, they used 4 or more GP60s on their intermodal trains as every added engine increases horsepower which increases speed
I think im wrong but I think you forget to add the C44 Dash 9
Run 8 doesent have em
Ive found out that any grade steeper than 1 in 40, requires the horsepower rating of each loco to be 8 times stronger than normal in order to climb the grade with ease
The outfit I work for would only use 2 engines for 150 grain or 150-200 car coal train from Roanoke to Norfolk! I'm guessing this video takes into account the Rocky mountains=steep grades. Still a great video.
Well if you see a CP video theres always single head leaders because they run on flat land.
CN uses between 2-3 per grain train 100-220 grain hoppers. CP 3 units on 110-130 and 4 units 2x1x1 on 148-170 odd cars
I work for them now. Our grainers are 116 cars and we use 3 locomotives. Ruling grade is a little over 1% on the route I'm on.
Also, a double has 232 cars and 8 locomotives. 3 in front, 3 cut in in the middle and 2 on the rear. 32,000 tons. They handle surprisingly well, just have to plan your stop an extra mile ahead.
@@jimvanorden6160 Yes ive had to do that in the sim, dynos is the word
@@hobartsignalproductions3994 are you on the Montana division? I heard they were making those guys do a sim run for the doubles.
Where did you get the gevo sounds from please???????
There the defaults the horns are from the depot
No matter how one figures how many locomotives are needed for a certain route, trains can still stall out. Photos and videos have been seen, of a stalled out train.
One or more power units, are still needed. Yes, it costs money and time to use extra power, above what was figured in. But the major railroads do have extra stored power. If ya got it, use it.
Sometimes, better safe than sorry.
Recognize all that background... The Cajon Pass
This science is interesting and very informative. Even though it is short, I enjoy it very much.
tractive effort is more important than horsepower, Saying that horsepower is what is moving the heavy train alone is like saying you could haul a 20k t with 3 TGV power cars (rated at 9,400hp each). Google Krug Tales Tractive effort V Horsepower to get a better understanding
Union Pacific uses 6 to move a 200 plus car grain train. That averages over 30,000 tons and 15,000 feet.
But grain is verry heavy ive seen a 4x3x2 grain train before
@@hobartsignalproductions3994 these are the dark days of PSR. So 2x3x1, or two 2x1 grain trains slapped together. Is the norm. If it only goes over a .9 grade hill at 13 mpg. Oh well. If it loses an engine and stalls. Oh well.
I see a lot of non railroad employees commenting on your video. And most of are wrong. Several months ago I had a lone GP15-1, A 135 ton FOUR AXLE switch engine, pull 115 loads 25miles from one yard to another. I never got above 15mph but that little sjmbitch got me to the next yard and didn't give up the ghost or overheat. By the way my railroad, U.P. usually assigned 3 A.C. LOCOMOTIVES to our 110 car grain trains. 2 pulling and one DPU on the rear.
I noticed nowadays some of the trains will have three engines in the front and one engine in the middle of the set.
Well done bro...keep up the good work...keep pursuing what interests you and you'll find a job doing something you enjoy!
I just watched somebody's science project because I got bored. goes to show my brain dead I am. nice video
For what it's worth there are many variables in moving trains.
I've run many trains with less than 1 HPT. Certain high priority trains are required 2+3 HPT to maintain schedule.
Speaking from experience. In western Canada cn rail routinely runs trains at 0.5 hpt. Not uncommon to see 3 engines (2 headend and 1 on the tail) of 170 loads. Max grade 0.7%.
One Big Boy locomotive will move that amount of cars without crackin a sweat.Theres a video of The Mighty Challenger pulling 143 cars over Sherman Hill at 35 m.p.h !! .These old steamers ain't no joke .
I can see for uphill and down hill speeds but do all locomotives have to run all the time under power or can one or two be at idle while on flat terrain to reduce fuel costs?
Locomotives can be run at idle if there in the middle of back of the train. Crews can use DPU fencing so that the DP units run sepertly than the front units, but this is mostly used for cresting a summit of a hill where the lead units can be in dynamic brakes and the DPUs can still be running power. Personalty I just run the units all the same on flat ground and instead pf being at notch 5 or 6 to maintain speed, i might just have my units at notch 2 or 3 saving fuel in all the units.
Even better with 9 locomotives.
That would be a very heavy train. It would take three or four of any of the engines you mention to get any speed.
These HP Rates are just a Number to simplify the Calculation.
What really Counts is the Traction Effort your Locomotives can bring onto the Rails.
An european electrical Loco with > 10000HP may be capable to move a Train at > 120mph but it will never be able to pull such enormous Loads.
Simple because of the Fact that American Locomotives weights twice as much as the european Locos.
I've seen maybe a total of 3 or 4 locomotives hauling that length of train the combos I've seen growing up are the standard 2 in the front and 1 at the back or I've also seen 3 in the front and 1 at the back or just all 3 in the front and none at the back I have a channel here on TH-cam that shows some of these combos if you want to go look
this video was interesting and I enjoyed it, however I have a couple of questions and i don't know all the correct terms. How is the Horsepower requirements determined for a train going over the cajon pass or other steep grades and also how are the number of electric motor breaking axles determined for the down hill side? Does a simulator exist for running a loaded train over the cajon pass?
The hpt requirements are set for different routes example Tehachapi has a minimum of 2.3 but generally speaking you always want more than 2 hpt. The crew determines the length of the train and the tonnage and what percent grade there going down they can set whole locomotives to cut out the dynamic brakes or individual traction motors. Hope that helps. and yes the sim e used has the Seligman sub needles sub Mojave sub Bakersfield sub Cajon sub and the san Bernardino sub just look up run 8.
@@hobartsignalproductions3994 Thanks for the information I find this stuff interesting. years ago we lived in the Sierra foothills and i remember the trains leaving Rocklin for Truckee and it seems that the trains had more engines then I have finders to count them, again thanks for the info.
Pretty cool video, one thing you need to factor in is weather conditions. There’s a big difference starting out on wet rain than dry rail and pulling steep grades
What about DPU? I've noticed different handing of trains with DPU vs without.
True, but that is a whole other equation. I am in 8th grade rn lol.
@@BurlingtonNorthernProductions lol. Must suck having to wear a mask. Glad I graduated last year, I could not even think I could handle that, without federal minimum wage.
your not taking in account the grades the train is going to incumber . You may need mid and rear DPU"S
True, I will get into that lol. I am in 8th grade honors science and this stuff is hard lol.
@@BurlingtonNorthernProductions Sorry No Problem didn't know your age
May be sometime just a set of maned helper, like MRL's engines at mid of BNSF's train.
@@pqhkr2002 That would never happen lol the best you would get is a ge demonstrator
it's gonna take 8 locomotives 4 in front 2 in the middle and 2 on the end.
of its raining then add 2 more locomotives.. if it's hot above 90* then add 2 more locomotives.
the reason! there are too many locomotives sitting idle in a few yards around the country. you've got the resources use them less fuel burn
Gonna offset fuel for maintenance costs then.
Or you could just throw 4014 on the head end and forget about it :P
And break a few knuckles
6 maybe 7, 2 on front, 2 DPUs in the middle, and 2 on the end
How would making two of the five locomotives D.P.U.s change the pulling power?
The real question is. What type of computer and desktop did you use to run that simulator.
In reality, I believe the Engineer has the final say on the number of locomotives used. Scheduling or whoever uses a formula for the lashup, but the Engineer knows the route and all up and down grades and the tractive efforts involved. We will find that they may go with a 3 or 4 engine lashup and then add in one or more Distributed Power Units (DPU's) to account for strain at the knuckles. Great exercise! Very informative :)
Having had my “engineers card” for 22 years I’ve never been able to pick or lash up my own power (I wish) but with the way the railroads run now is straight money saving mode ... I’ve been told to run a 7000 ton freight train with one motor online and it takes an act of god to turn that 2nd loco online but it’s their RR .... they late 90s and early 2000s were a lot better .... give me 3-4 SD60s old school cabs and let me go !
@@sirt7286 Understood - "management" thinks they know everything :) EMD's would be my choice - even SD40's!
Brian, you made my day! 😂 The only say an engineer has these days is on the height setting of their chair.
your formula only works on flat terrain, real railroads use grade charts, real railroads go up hills and through mountains requiring much more HP !!
I remembered in Run8 guide, Mojave Sub or Cajon Sub, they need at least 2.something, intermodel usually 5 or more.
Here's a railroad, rail fan question.
A single locomotive is pulling 45 cars at 100 miles per hour. The train has traveled 79 miles straight at the 100 mile per hour speed. What was the name of the engineer?
Moses.
Very interesting video idea!
what am I missing here ? what happened to Traction Effort ? just asking, as my old brain cells remember correctly, that use to be a guide in figuring things ?
That and how many locomotives does it take to stop 174 loaded grain cars...
Sure, 1 or 2 might still start the train, but if it happened to be going downhill, then oof
@@Unsound_advice Only one. The leader would release air setting up the brakes on the cars and that would stop the train. It is all about the grade. 20,000 ton, 210 car grain train with 2 on the head three dp's and one on the rear will pull 1 percent grade. Not fast about 10mph. up hill.
@@papa45colt47 unless dynamic braking is your first priority of braking per ABTH. Learn sarcasm.
@@Unsound_advice the question was how many to stop. You technically only need one. Dynamic brakes are the preferred but not the only way to stop it.
The European Version of this: How many trucks do you need to haul the same amount of grain. :-)
115 cars gets 3 units for most of the trip. Double grain trains get 6.
INTERESTING --- I wonder what role the position of the locomotives would play in actually accelerating the train to 15 mph assuming 0% grade, same number of locomotives, same horsepower, and no wheel spin. Does having 3 locomotives up front, and say, 2 locomotives in the middle help vs having 5 locomotives up front? Apparently, a lot of trains are configured this way and so there must be an advantage.
The main difference is you'll be able to get the train moving a little better, because the DPU will be pushing at the same time you're lead is pulling compared to just everything up front. Also think about the fact you can only have some much pulling power on the head end due to the metal breaking point of the couplers.
& if it was down to only one engine on that train, it'd be the little engine that could.
One. But it needs to be quite powerful.
Interesting, also what simulator is this? Trainz?
The simulator is Run 8
@@cnrailfan3473 Trainz Driver 2, Pocket Trains, Turboprop Flight Simulator, Infinite Flight, X-Plane, Aerofly.
Very interesting video! Nice work!
Good vid. I'm assuming putting power on the back end shortens the time it takes to get the consist moving since a lot of slack action at startup is negated. All the major haulers have gone to that model or with mid units. Would be interesting to see the math on 2 headers and 2 pushers.
Overall, makes sense for 5 Locomotives to pull it. I thought you needed more than 10 locomotives. It's not about how long the train is, it's about how much power it can take to move it. A+. Also what is that simulator called?
Its more about ho hevey your train is and your hpt. The sim we used is called run 8.
@@hobartsignalproductions3994 Alright, I'll try it, and you guys did a nice job.
What if a crew member didn’t get all the hand brakes off or you have units that aren’t loading properly. Then there’s the sanders. Are they working? Seems like less employees means less things work as in a perfect world. Don’t forget about the weather and who is behind the throttle. I used to call engineers plastic stick jockeys.
You can move cars down hill with release of air and hand brake.
30K gallon Tankers are the most heaviest for locomotives in axle loads
100 tankers will need 3 locos at least to run in average 65 km/hr
You also need to add in the weight of the cars too
would mid-train locomotives altered this?
There are other variables to consider it is not a simple pulling equation. Track physical condition, crossings and switches, curves and there radius, wind speed and direction, atmospheric conditions (weather), physical condition of the cars (wheel profile, bearing condition, load distribution), need to keep to a schedule ( speed, acceleration, stopping distance). Always have a small safety reserve on theoretical max power calculated. One loco down on power would tip the balance.. Recent example on video of a train stalling on Horseshoe pass because it only had one locomotive. The train stalled just as it entered the tightening curve above the camera position at the observation building. Theory could dictate one loco for the load, the track conditions (only 1 year old) and the hill but add the curves it was too much.
Thanks. Now have a seat in the corner.
So we need 40 trains to run snowpiercer
It takes almost no power to move any grain car except to overcome bearing friction. Famous strongman Charles Atlas proved that in the 1930s pulling a Broadway Limited observation car with a rope. The trick is how fast. Horsepower (foot-pounds per hour) is not tractive effort (pounds), and trains require more HP as train speeds increase (tractive effort x speed). Add a grade and the drawbar pull increases dramatically since you're not just overcoming rolling resistance but actually lifting the train up a ramp.
Instead of relying on someone's video game, a college course in Newtonian physics would be a better place to start.
Dam Its so cool
Thanks man!!
@@BurlingtonNorthernProductions You Got It!!!! also check text when you get the change lmao i cant spell
What train sim games are these in?
Even I was wondering the same , hope someone answers .
Run 8 just look it up
on flat level ground (or at least mostly level) 1 locomotive can move 174 loaded grain cars. you see this in the real world all the time for those that sit at the crossing and count the cars.
if you really want to test this. then how about doing the experiment again but with more than 6 locos. like a ridiculous number like 10 or 20 locos. what happens then?