Hump yard elevations

[davedingler]

Hey All,

My route has a hump yard, Englewood Yard, in Houston, TX. Question: Does the DEM that I've imported into my route accurately represent the elevations of the area that the tracks are running in? Also, highway and rails that pass through an underpass.

Photos are captured views from Google Maps.

Englewood hwy rail overpass.jpg

The elevations around this bridge range from about 45ft under the overpass to about 69ft just east of the bridge abutment. The lowest elevation in this area is about 41ft just south of the bridge. Just west of the bridge the elevation is about 66 ft and slopes to the north and south to about 37-38 ft. Where the separate tracks divide to different areas of the yard the elevation ranges from about 48ft at the main line split to the largest yard group. Its about 46.5 ft at the split for the 8 track yard section. The main yard elevations range between about 44 ft to 49 ft with some more than 50ft. The surrounding area street level elevations vary between about 45ft to 39ft.

Elevations values can be found using this URL: http://www.freemaptools.com/elevation-finder.htm

Englewood Yard.jpg

Englewood8.Yard.jpg

As you can see, there are a lot of areas of different elevation within the yards and I'm wondering how important it is to accurately incorporate the elevations. The only reason that I can visualize is that if someone were to create a scenario for a hump yard activity for a yard master or consist builder to assemble different train configurations.

If accuracy is required and if the DEMs do not incorporate the elevations accurately then how does one go about manipulating the terrain to achieve the accuracy?

Hope I haven't bored you too much,

Dave

[PolyesterMafia]

An accurately elevated hump yard in TS most likely will not work, unless there have been some major physics changes made to the individual freight cars in the game with the latest incarnation. As soon as you uncouple the cars from the locomotive, the brakes apply on the car. I built a hump a couple of years back and it took an extremely unrealistic grade (locomotive pilots digging into the ground) just to kick the cars a few feet down the other side of the hill.

[RAILSOHIO]

So again another good reason to let RSC know we need the ability to "bottle the air",in cars,so that cars can be kicked,dropped,and humped.(Sounds abusive kinda,I know) I just don't think the Brits understand just how common this is,in the good ole USA. My comment is not to discourage you from building a hump,just know that there is not a practical way to use it,at this time.

[thebigroyboyski]

Hump yards used to be very common in the uk too. There is even one on the WCML add on route, Carlisle Kingmoor Yard. I haven't explored the yard to see if the hump has been built though. It might be worth a try checking over at UKTrainSim and seeing if anyone has found a solution there.

[PolyesterMafia]

This issue also affects marshalling operations in regular yards as well. You can connect to a cut of cars and move them from the end of the classification yard to the departure yard just fine. But once you drop them, even if you don't set the brakes, they lose their air. When you come back with another set of cars, connect them to the original set, and begin pushing to move them further down the tracks, it's obvious the brakes on the first cut are applied.

[DonR]

In real operations, what do they do for cut cars? Just leave them unbraked, or set the hand brake?
You would think that in RW... er... TS14... when you hook up to a car(s) the air would pump up and release the brakes. Is this a bug?

Having the ability to realistically classify cars with a hump yard would be awesome.

Don.

[BNSFdude]

In a hump, they are bled of air brakes entirely, no hand brakes. Computer control will automatically route the cars or cut of cars to the appropriate track, and retard their speed accordingly so that they will make it to a joint with the currently residing cars at an acceptable speed.

[mrennie]

In a hump, they are bled of air brakes entirely, no hand brakes. Computer control will automatically route the cars or cut of cars to the appropriate track, and retard their speed accordingly so that they will make it to a joint with the currently residing cars at an acceptable speed.

I saw a video on YouTube of a SP movie from the 1950s, showing a hump yard being operated by a chap in the tower, pressing buttons on a panel, to send electrical commands to a gizmo on the track that physically squeezed the flanges of the cars as they passed, slowing them down. He was so expert at it that he could squeeze it just the right amount every time.

https://www.youtube.com/watch?v=SspN6D3uF3s (from about 11:40)

[PolyesterMafia]

Those flange-squeezer thingies are known as retarders, at least by us foamers. I visited neighborhood near DeButts yard (Chattanooga, TN) not long ago and you could hear those things 24/7 as the cars roll through. It sounds like the flange squeal as a train rolls through a curve.

[thebigroyboyski]

I've had a wee think about this and I don't know why this didn't come to me sooner.
In the uk a lot of the early wagons didn't have brakes at all, except hand brakes. I don't know if in the game this is true though. If it is we could swap the bin info over and have special brake less cars just for yards.
Our equivalent of a caboose was called a brake van because it was used to keep the train tight.

[davedingler]

Hey All,
Thanks for all your replies. All very interesting and informative. However the questions in my original post were:

1. re: DEM imported to route- Does the imported DEM capture the accurate terrain? That is will the hump and slopes and other depressions be there and will the track snap to the terrain if they are?

2. If the DEM is not recording accurate terrain, how does one go about creating it, if it is needed?

I'm not at the stage of even thinking about creating a scenario for the hump yard. I'm just trying to determine if it is anything that needs to be dwelled upon for accuracy or just general elevations in the yards.

Thanks,

Daave

[FoggyMorning]

Hump yards used to be very common in the uk too. There is even one on the WCML add on route, Carlisle Kingmoor Yard. I haven't explored the yard to see if the hump has been built though. It might be worth a try checking over at UKTrainSim and seeing if anyone has found a solution there.

It is modeled post-removal of the hump on the West Coast Main Line Route. It is present in its full condition on the Western Lines of Scotland route, but it has been built without the hump being modeled. The same applies to Tyne Yard on the York-Newcastle East Coast Main Line route.

[OldProf]

This issue also affects marshalling operations in regular yards as well. You can connect to a cut of cars and move them from the end of the classification yard to the departure yard just fine. But once you drop them, even if you don't set the brakes, they lose their air. When you come back with another set of cars, connect them to the original set, and begin pushing to move them further down the tracks, it's obvious the brakes on the first cut are applied.

If you're referring to the player-driven engine, I have to disagree with you about this, and I do so on the basis of having written numerous switching scenarios and played many more. When, as the engineer, you re-couple to a set of previously dropped cars, their brakes are released immediately, as can be seen by clicking on the HUD's coupler icon and watching the pick-up take place there. If moving the resulting train seems more taxing than it was before picking up the additional cars, it's only because the train as a whole is, naturally, heavier.
In fact, there's no visible way of determining that brakes are set on a static or uncoupled rack of cars, since they do not appear in the HUD until the player engine couples to them, at which point their brakes are released until the player sets them by clicking on one or more of the brake icons. The fact that cars do not roll downhill after being uncoupled regardless of whether their brakes have been manually set by the player suggests, of course, that their brakes have been set by -- why not? -- the dispatcher or some invisible brakeman or even the ubiquitous Dan Hernandez, but there is no other proof of that. The notion of simulating an operational hump yard has been rehashed many times in this and other forums, but it strikes me as another of those moot discussions that keep us all busy, if not content. At present, RSC -- pardon, Dovetail is asking in the TS forum at Steam for serious suggestions regarding modifications to the game engine. Perhaps one of you frustrated humpers will see fit to make the appropriate suggestion?

[Mazherman+75]

I worked for CPRail at Alyth (in Calgary) which has a hump yard. Everything is now computerized : the cars are weighed by the scale that is part of the hump and the computer takes the weight and distance to go to the classification yard, curvature of the track and then "commands" the retarders to squeeze more or less depending on the circumstances. The Retarder Operater watches the going-ons and can interfere if needed.

Always was fascinated by it.

[Toripony]

Dave, the accuracy you're asking about will probably only be available (if at all) in 1/9 arcsec data from USGS and there are very limited areas that were scanned at that high resolution. Most of the U.S. data is 1/3 arcsec which probably won't accurately display the depth/height of a hump yard. When I tried this with the Bailey Yard in Nebraska, the hump was fairly close but rounded off and the "pit" was barely discernable when in reality it goes several feet below the surrounding landscape (I forget the exact numbers). So, I laid all the track level, then painstakingly selected 64 gradient markers simultaneously and lowered all the tracks to the grade I wanted, then snapped the terrain to the track. IIRC, I actually set two grades; something like 1.5% at the "head" tapering off to .5%.

The reason your thread keeps going off topic is no one has made this idea work so we don't really know if a prototypical hump yard grade will work or if it will have to be exaggerated. If exaggerated, how much? And then, how do you slow the cars. Ultimately, the answer to your question lies in the brake physics of the rollingstock in the game and how to hack them.