In thuis guide I'll explain the signalling systems for the UK, Germany and US in a basic way, without overcomplicating stuff. I'm trying to cover both light signals and semaphore signals, and perhaps some stationary signs, as best as I can.

Signals are usually located on the same side as the trains drive. So on countries where trains drive on the left side, such as the United Kingdom, signals are placed left of the track. In countries where trains drive on the right side, such as Germany and the United States, signals are placed right of the track.

Exception is railways with two parallel tracks. In that case they're placed on left side of the left track, and the right side of the right track.

The UK probably has the easiest signalling system as signals do not give any speed restrictions.


A single green light means clear




A double amber light (two lights above each other) means the next signal is showing a single amber light



A single amber light means the next signal is showing a red light



A red light means danger. You should not pass this signal.




A red light with one or two white lights means danger, but slow speed movements allowed. Basically it means you should drive slow enough to stop for any obstacle. It's often used whenever the track is occupied by a formation you should be coupling to.




A double flashing amber light is used to let you reduce speed because you're being diverged into a sideline with a lower speed limit. Static signs should tell you the speed limit. This signal is followed by a single flashing amber light.



A single flashing amber light is used to let you reduce even more speed because you're being diverged into a sideline with a lower speed limit. The next signal will display an illuminated feather to indicate to which track you're being diverged. This image shows an example of such a feather signal.[dtl-ghost-storage-bucket-prod.storage.googleapis.com]



A single flashing white light is used to indicate the level crossing ahead is safely closed for road traffic.


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When a signal is fitted with an illuminated number, the number indicates the track you're being routed through. It's used instead of a feather and common on those places with a lot of tracks. Alternatively an alphabetic character may be used to indicate the route being set for you.



Repeater signals are used whenever the view on the next signal is obstructed. Repeater signals indicate the aspect the next signal is displaying. When a repeater signal shows a white light with a horizontal black banner, the next signal is at danger (red) and you should expect to stop.



When a repeater signal shows a white light with a diagonal black banner, the next signal is at caution (amber).



When a repeater signal shows a green light with a diagonal black banner, the next signal is at proceed (green).

There's two types of semaphores in the UK. Red ones are main signals, indicating wether the line is clear or at danger (comparable to a green, or a red light). Yellow ones are distant signals, indicating the state of the next main signal (comparable to a green, or an amber light). When in a horizontal position, semaphores are in their restrictive position (caution/danger aspect). When in a diagonal position, semaphores are in their safe position (clear). Semaphores may be fitted with small colored lights, but those aren't as bright as modern light signals.



This is a distant signal giving you a clear aspect. Basically it's comparable with a green light. UK distant semaphore signals can protect one or more main signals. This distant signal indicates all main signals up to the next distant signal are clear.



This is the main signal giving you a clear aspect. It's comparable with a green light.



This is a distant signal showing caution aspect. Because distant signals can protect one or more main signals, it's possible that the next main signal still shows a clear aspect. You should however expect at least one of the main signals to show a danger aspect, until you pass another distant signal.



This is the main signal showing danger aspect. You may not pass. It's comparable with a red light.


Main signals can also be fitted with a distant signal. In such a case the distant signal will tell you the state of the next main signal. For example:




This is clear aspect on the main signal and another clear aspect on the distant signal. You're clear to proceed and can expect the next main signals to also be clear.




This is a clear aspect on the main signal, but the distant signal on caution aspect. This means you're clear to proceed, but should expect to stop at an upcoming main signal.




This is a danger aspect on the main signal. You're not allowed to pass. You can ask the signaller for permission to pass, but should expect the next main signal also to be at danger.


At yards or switchovers it's likely that there'll be multiple semaphore signals. They will be placed next to each other and each represents the routes your train could take. One signal will be located higher than the others and will represent the main line. For example:




The upper signal is showing a clear aspect, which means you will be routed over the main line.




The upper signal is showing danger aspect, but another one is showing a clear aspect. This means you will be routed over to a side track. Many of those have a lower speed limit. There's usually signs indicating what exactly the speed limit is (or you can rely on the HUD).

"Whistle" sign, most commonly found on modern routes. It tells you you should sound the horn (or whistle, on steam locomotives)



"Sound whistle" sign, most commonly found on historic and heritage routes.



x "Car Stop" sign, you can find several of these on modern platforms, telling you where you should stop based upon the number of cars your consist is made up of.



Found on modern routes, indicates an upcoming speed limit in miles per hour. If the sign shows two numbers, the lower number applies to freight trains, and the higher number applies to passenger trains.



Found on modern routes, indicates a speed limit in miles per hour. If the sign shows two numbers, the lower number applies to freight trains, and the higher number applies to passenger trains.



Found on historic routes, indicates an upcoming speed limit in miles per hour.



Found on historic routes, indicates a speed limit in miles per hour.

In Germany there's two systems which are pretty similar in how they work, but there's variations on what the aspects look like. The Vr/Hp signalling system relies on a distant signal, or "Vorsignal" in German, informing you about the state of a main signal, or "Hauptsignal" in German. A distant signals only job is to inform you of the state of the next main signal. As such a distant signal is important as it gives you new information. The main signal should not have any surprises for you.


To warn you a distant signal is near, there are boards with diagonal stripes counting down as you get closer to the distant signal.


Distant signals are marked with a white sign showing two triangles pointing to each other, forming a cross.

On the most common signalling system used in Germany, distant signals have their lights in a diagonal position, which makes them distinguishable even in the dark.




A green-green distant signal means the next main signal is displaying a green light, which means the line is clear and you can proceed.




A green-amber distant signal means the next main signal is displaying a speed restriction. By default this restriction is 40km/h, unless the signal is accompinied by a number.






When a green-amber distant signal is accompinied by a number, located below the signal, the number gives the speed restriction in units of 10km/h. So when the number 6 is displayed, the speed restriction at the next main signal is 60km/h. This number is often an illuminated signal, but could also be an ordinary sign.




An amber-amber distant signal means the next main signal is displaying a red light, which means you need to stop at the next main signal.




In my experience the distance between a distant signal and a main signal is 1km. When a distant signal is accompinied by a smaller white light like in the image above, it means the distance to the main signal is shorter than usual. There are places where there are multiple distant signals before the main signal, especially on places where the line of sight on the main signal is blocked. Any follow-up distant signals will have such a small white light, and will not be announced by the distance beacons (the signs with the stripes counting down).


When approaching a main signal you should not come to any unpleasant surprises, since a distant signal already informed you about the main signals aspect.


A main signal displaying a green light means the line is clear and you can proceed.




A main signal displaying a green and amber light means you're clear to proceed at a reduced speed. The default speed restriction is 40km/h unless otherwise specified.





When a green-amber main signal is accompinied by a number, the number indicates the speed restriction in units of 10km/h. In the example above, the speed restriction is 60km/h.



A main signal displaying two red lights means danger (stop), and you may not pass the signal.






A main signal displaying one red light and two small white lights means the line is at danger, but you may proceed at very slow speeds. You should drive slow enough to be able to stop for any danger. This signal is often used when the line is occupied by another train to which you must couple.


Main and distant signals are described above are often combined. In such a case the main signal will always be placed on the top, while the distant signal is located directly below. The distant signal displays the state of the next main signal.

For example:









This could be all the lights you see at one signal, and looks very complicated. Just split it up in two parts; the upper part is the main signal and should contain no new information. The lower part is the distant signal telling you the state of the next main signal. In this case the main signal is giving you a 80km/h speed restriction and thus you may pass this signal at max 80km/h. The distant signal is indicating a speed restriction of 60km/h, so you should slow down and expect to pass the next main signal no faster than 60km/h.

On some lines the Ks signalling system is used. This signalling system is based on the Vr/Hp system described above, but simplifies aspects by merging the distant signal and the main signal in one signalhead.



A green light means you can pass the next main signal. You can proceed at the maximum allowed speed for the line.



An amber light means you should expect to stop at the next main signal.



A red light means you should stop and not pass this signal.





A red light with two smaller white lights placed in a diagonal position means danger. You may proceed at very low speeds so you can stop for any obstacle you meet. This aspect is often used when the tracks are occupied by a train you should be coupling to.



As with the Vr/Hp signalling system, a small white light at the left side of the signal means the distance to the next main signal is shorter than usual.




A flashing green light with an illuminated yellow number beneath it, means the next main signal shows a speed restriction. Similar to the Vr/Hp system, the number displays the allowed speed in units of 10km/h. In this case you should slow down to 60km/h and not pass the next main signal any faster than 60km/h.




A green light with an illuminated white number above it means the speed restriction starts at this signal. In this case you should not pass this signal any faster than 60km/h.


The signal aspects above can be combined. For example:





The speed restriction starting at this signal is 80km/h, the next main signal will give you a 60km/h speed restriction.




The speed restriction starting at this signal is 60km/h, and you should expect to stop at the next main signal.

TO DO
German semaphore signals aren't present in any of the TSW routes yet.

A signalhead showing a yellow dot painted on it is used to protect railroad crossings at branch lines. There's a light located beneath the yellow dot. When the light is off the railroad crossing is not properly closed and you should not pass the railroad crossing.



When the white light flashes the railroad crossing ahead is properly closed and you can safely pass the railroad crossing.



Milage posts are commonly placed at every 200 metres. The upper number is the kilometers, the lower number the units of 100 metres. In above example, it's 83,6km.



"Halt" sign, indicating where passenger trains should stop on a platform. The sign can be supplemented with a sign indicating a stop position for a "Kurzzug" (short train), "Halfzug" (half train) or "Volzug" (full train), as well as a distance in metres to indicate the length of the trains that should be stopping at this sign.



Whistle sign. The P stands for "Pfeifen", which is the German word for "Whistle"


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A yellow triangle sign with a black number indicates an upcoming speed limit reduction. These signs are commonly placed 1km ahead of the speed limit reduction. The number indicates the upcoming speed limit in units of 10 km/h (so in this example, "12" indicates 120 km/h.



Line speed limit, in units of 10 km/h. Note that speed restrictions given by signals may still apply.

Unfortunately signalling systems in the US aren't standardized and every railroad or railroad operator may use their own variants. This makes US signalling pretty hard to learn and explain. There's signalling charts for several railroad operators on the internet, but in my experience they're hard to learn and I could never really find a logic in them. In an attempt to make things slightly easier, I'm just going to explain what I've learned about US signalling and what tricks I use to remember at least some bacics.

Position lights vs Colored lights
US signals come in many shapes and forms. Most railroads use colored lights, but some use position lights. In TSW the Long Island Rail Road (LIRR) uses position lights.
lights in a horizontal row equals a red light
lights in a diagonal row equals an amber light
lights in a vertical row equals a green light
Position lights could either be yellow or white. Most have 3 lights in a row, but on LIRR there's some tiny signals located close to the ground which only use 2 lights.

Even though there's no standard for US signalling, there's a few signal aspects which are equal to all railroads I've seen.

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When the top signalhead is green and any other signalheads below (when present) are red, it's clear to proceed. Basically you can ignore any of the red lights. The red lights are only there to let you know the signalhead is functional. So, a green signal equals a green over red, and a green over red over red signal aspect.

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When the top signalhead is amber and any other signalheads below (when present) are red, it's a caution aspect where you should expect to stop at the next signal.

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When all the signalheads are red, not flashing, the signal is showing a danger aspect (stop). Do not pass this signal. This one is easy to remember; Only when it's all red, then it's a stop.

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When one of the signalheads is showing a red flashing lights, and any other signalheads (when present) are red, you're allowed to proceed at very slow speed. This also applies to when a fully red signal aspect (all red) has an additional white light. These signals are typically used to enter yards, dead ends or track occupied by a formation you should be coupling to. You may need to manually set switches. Drive slow enough to stop for any obstacle you see.

TO DO

"Whistle" signs come in many shapes and colors, but generally they all show a big "W" on them.