It appears that the signal indications entering sidings is frequently incorrect. I have seen trains entering sidings with green-over-red instead of red-over-yellow and trains having the same signal indication taking different routes at the same siding (CRR 97 and First Greenbriar Turn, Part 2 at the south end of Trammel, for example). I'm not sure if this is because the signals are using the path of the train instead of the track configuration to determine their indication, or if they cannot handle the situation when the siding exit signal is already clear when a train reaches the siding entrance, defaulting to green-over-red instead of red-over-yellow for entering the siding. Either way, this is a rather notable issue with an otherwise great route.
To date, until somebody publishes a guide, I don't think we know what was "correct" on the Clinchfield. I have heard that their signaling system was idiosyncratic even by American standards, and there has never been one unified "US" signaling system! Every railroad has its own (in the case of CSX, several, from all the RR that went into it). Just because an aspect means one thing on SPG, what it meant on the CRR might have been entirely different.
This article about signaling on the Clinchfield plainly states in the Color-Light Signal section that the top set of lights is for the main and the bottom is for the siding, and that the installation followed AAR standards. There did seem to be some interesting additions that might be considered unique, but I don't think that allows for the fact that green-over-red would sometimes mean to take the siding and sometimes mean to stay on the main. Otherwise, why bother with the expense of an additional set of lights?
It may be the case, as according to Matt was the case at the Trammel siding, that in some places the straight-ahead route was the "siding" and the divergence was the "main." Or it might be that CRR kept to a right-side standard, and that green/red meant "Stand on; proceed" whereas yellow/red meant "Give way, prepare to stop at next signal", without always putting the give-way train on the divergence: trains would always keep right, whether stopping or proceeding. Since the main line was limited to 30 mph or less, there was no need to slow down for a turnout. Now that I think about it, so far playing the route I have never passed an oncoming train other than left-to-left. One hopes somebody could dredge up an old CRR manual from back in the day. PS: the article doesn't really say "the installation followed AAR standards," if by that you mean AAR recommended signaling. All it says is that CRR used AAR-standard light hardware. The installation was definitely idiosyncratic even in what we can glean from the article, since rather than place signals between tracks CRR used doll posts and blue lights on the right side.
US signals are easy. This line really is not any different than any other one. Top head green yellow red Bottom head red lunar white. Only reason to show restricting on this line is for entering / leaving sidings. G on R is clear Y on R is approach R on R is stop R on LW is restricting And guide is on the way, just trying to get an image of a signal showing restricting however it may be the case that it won't show it because it is bugged. Working this afternoon on it and yeah I have a bunch of rule books, not CRR but I do have about 2 or 3 CSX ones as well as about oh 70 other railroads...lol Very simple, the fact is this line has bugged signals and that's as simple as that.
I'm somewhat confused by the function of dwarf signals here, because, oddly, they often appear to contradict what the mast signal is saying. For example, green while the mast is red/red.
In most cases I have seen, the dwarf signals are for the siding and the mast ones are for the main, so only one will be green at a time at a siding exit. It's a little odd because signals are typically next to the track they are controlling, but due to space limitations, Clinchfield settled on dwarf for siding and tall mast for main, regardless of physical proximity to the track. Maybe there's a specific configuration I haven't seen, but that's the general idea.
Or the dwarf is for the adjacent (right hand) track, while the mast (with dolly pole) is for the left hand track, regardless of "main" and "siding" status.
The article I linked earlier clearly states that the mast signal is for the main and the dwarf is for the siding, and this agrees with vogelm10's signaling guide for the route.
You're both right. I just used the terms sidings and main track in order to differentiate the two. I totally could say mast for higher speed route, dwarf for lower speed. But concept wise both are correct, same thinking different wording!
This is showing clear for right track. And this is clear for left track. So technically in the top example the through line is the one with the dwarf signal.
Why could that not be intentional? If the siding exit is already clear, there would be no need to show an Approach aspect.
The engineer needs to know whether to slow the train for the siding vs. maintaining speed on the main. Especially if it's the case that the indication is red over lunar for entering a siding, as stated by vogelm10. That means sidings must be taken at restricted speed, as occupancy of the siding is not set up to be detected by the signaling system.
From what I've found out so far, you as an engineer need to know exactly which sidings you will take and where you will hold the main. Maybe you'd get that list written down or by radio IRL? I'm not familiar with operations of that era... The entrance signal is there just to tell you the aspect of the exit signal, but does not convey any information on what route you are taking.
NA doesn't use entrance and exit signals. The aspects do convey which route you take based on speed. So when you approach a siding you'll see the signal has 2 heads. This is so it can show restricting which is as you mention an aspect that means the area ahead may be occupied. 15 mph prepared to stop short of next signal or obstruction. That technically could apply to a straight route too, but based on the fact they only place 4 aspect signals in those locations would mean that they seem to use it to show to take the siding.
Actually it was (and presumably is) much much simpler than that: I've run it several times now paying careful attention- at passing loops CRR always routed trains to the (their) right. Just like automobiles (except in Britain). Also, it was a pure speed-signaling system with no route-signaling element, so "main" and "siding" didn't mean all that much, nor were "divergence" signals employed. The logic is straightforward: the engineer only needs to know how fast to go, not where he's going, because he can only control the former not the latter. And, given a 30mph top speed, there was no need to reduce speed for turnouts.
The problem is that that's not exactly how it works in the game at the moment. I took the Extra 3005 North and I encountered three sidings where signals showed either Clear or Approach, but the HUD speed limit was 15 mph through the entire siding. I suppose that's TSW's way to tell you that you should go at restricted speed, but signal aspects clearly do not reflect this. The speed limit when going southbound on the main through the same areas was usual 30 mph. So if playing HUDless, you either have to know what sidings you'll use, or treat all siding "entrance signals" (I understand that this is not a correct term) as showing restricting (as you wrote, always suppose you will take the right track), or simply overspeed.
It appears that Restricting aspects are currently bugged. The game has Divine 15mph Limits dropped into the HUD from on high, but no speedboards and certainly no signals. Properly, the lower head should be showing both lights (Red/White), meaning "Restricted Speed: slow enough to stop in one-half visual distance, not more than 15mph"
Do you have any documentation for this? I'm pretty sure trains always go to the right is because the TSW dispatcher cannot handle optional paths and so the trains had to be programmed this way to avoid standoffs. If you are somehow implying that it's correct because it's in the game, then I have some signals in NEC and LIRR I'd like to sell you.
I'm only describing what I have observed, together with what is known of Seaboard and Seaboard-territory CSX. That, and the fact that it makes no sense otherwise, and it certainly is a false trail to start ascribing route signaling to CRR.
