Written by: TrainSim-James
There are many intricate systems that railroad engineers have to master before being qualified to run out on the main, and none are more important than signalling.
In principal, signalling exists as a system used to regulate and direct traffic along the railroad, ensuring that trains are kept clear of each other at all times. The first timetables were a key step into the world of regulated rail travel, and as numbers grew for both passengers and freight, a plethora of varying systems were developed around the world, and today’s complex signalling makes trains one of the safest and most reliable methods of public transport to date.
CSX-operated subdivisions tend to have 1 of 3 main signalling systems, derived from the fallen flag predecessors of the nation, and also feature newer, standardised installations post-merger. Crawling through the Alleghenies of Maryland and Pennsylvania, the Sand Patch Grade route, as featured in Train Sim World: CSX Heavy Haul, has seen most of it’s ex. B&O-type colour light signalling replaced with a much more modern, ‘vader’ style hooded head type.
Unlike signalling in the UK, which is predominately route-based, US signalling systems are typically speed-based, where different signal aspects instruct the engineer to pass at a specified speed, expect an upcoming reduction in speed, or of course, stop completely.
To be able to understand Sand Patch Grade’s signalling aspects and procedures, we’re going to need to run through a bit of terminology first. In the real world, exactly citing key phrases over the radio is an essential for a safe and reliable railroad, so do try your best to learn these off by heart for the most authentic results.
- Maximum Authorised Speed – The highest speed permitted for any train on a subdivision or portion of a subdivision
- Normal Speed – A speed between 46 mph and 79 mph, any speed above 79 mph requires in-cab signalling to be present
- Limited Speed – A speed not exceeding 45 mph
- Medium Speed – A speed not exceeding 30 mph
- Slow Speed – A speed not exceeding 15 mph
- Restricted Speed – A speed that will permit stopping within one-half the range of vision. It will also permit stopping sort of a train, a car, an obstruction, a stop signal, a derail, or an improperly lined switch. It must permit looking out for a broken rail. It will not exceed 15 mph.
- Controlled Speed – A Speed that will permit stopping within one-half the range of vision. It will also permit stopping short of a train, a car, an obstruction, on-track equipment, or a stop signal.
Note: these definitions are specific to CSX, other railroad operators will often have their own terms and definitions. Make sure you get to know the right ones, as written above, for Sand Patch Grade!
While it might not be initially clear as to how these help you learn the signalling system, just be patient. Many of the signalling aspects take these terms into account, so it’ll be important to know what kind of aspect you are approaching and how you need to act next.
In addition to various aspects, there are also different signal types; standard signals come in a few shapes and sizes and are found on the main line, easily visible from the cab of a locomotive. Dwarf signals are typically found in yards, nestled between tracks where there is no space for a main signal installation.
So, without further ado, let’s run through the most common aspects you may find shining ahead of you while railroading in CSX Heavy Haul. You may right click on the diagram below to open an enlarged version in a new tab or window.
Note: a signal head with radiating lines indicates a flashing aspect.
- Clear – Proceed
- Approach Limited – Proceed, approaching next signal not exceeding Limited speed.
- Limited Clear – Limited speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed at posted speed.
- Limited Approach – Limited speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed, prepare to stop at next signal.
- Approach Medium – Proceed, approaching next signal not exceeding Medium speed.
- Advance Approach – Proceed, prepare to stop at second signal.
- Medium Clear – Medium speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed at posted speed.
- Medium Approach Medium – Medium speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed, approaching next signal not exceeding Medium speed.
- Medium Approach Slow – Medium Speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed, approaching next signal not exceeding Slow speed.
- Medium Advance Approach – Medium speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed, prepare to stop at second signal.
- Approach Slow – Proceed, approaching next signal not exceeding Slow speed.
- Approach – Proceed prepared to stop at the next signal. Trains exceeding Medium speed must immediately begin reduction to Medium speed as soon as the engine passes the Approach Signal.
- Medium Approach – Medium speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed, prepare to stop at next signal.
- Slow Clear – Slow speed through turnouts and crossovers, sidings, and over power-operated switches; then proceed at posted speed.
- Slow Approach Slow – Slow speed through turnouts, crossovers, sidings, and over power-operated switches; then proceed approaching next signal not exceeding Slow speed.
- Slow Approach – Slow speed through turnouts and crossovers, sidings, and over power-operated switches; then proceed, prepare to stop at next signal.
- Restricting – Proceed at Restricted speed.
- Restricted Proceed – Proceed at Restricted speed.
- Stop – Stop before passing the signal.
A typical stopping procedure, which you will encounter should another train be occupying the track ahead of you, is Clear, Approach Medium, Approach & Stop. This simple sequence of aspects ensures that you are able to safely reach Medium speed before approaching the final Stop aspect; long manifest, autorack or coal trains carry with them a lot of momentum, and it can take miles to come to a safe stop, especially on a down grade!
To help you learn just that little bit quicker, here a few basic pointers on CSX Signalling.
- If a signal isn’t all red, it isn’t red at all
- Where signals have more than one head, subsequent heads define the speedband they are signalling, on their aspect, by the least restrictive colour. The bottom head will be a slow aspect, the middle head a medium or limited speed and the top head will represent line speed.
- There are two signal types present on the Sand Patch Grade route, those with ID Plates present, and those without. Signals without ID Plates are called ‘absolute signals’, these control an interlocking and cannot be passed without permission from the signaller if red. ‘Permissive’ signals are denoted by an ID Plate, and can be passed when red if they remain so for a given time and the signaller is contacted.
In Train Sim World: CSX Heavy Haul, the HUD is able to provide as little or as much information about the signalling as you desire. As you begin learning the ropes, it might be handy for you to know when you’ll be passing the next signal, and what general aspect it will be. As you advance your understanding of the signalling, you could decide to only see where the signals are, but have no indication of what the upcoming aspect is.
Once you’re a master of not only the signalling, but have gained route knowledge as well, you can even decide to drop all indications of the signalling from the HUD; you have to know where each signal is, and keep in memory what the previous aspect was and what to expect next. Further details can be found in the screenshots and captions below.
That’s everything you need to begin learning the signalling used on the CSX Keystone Subdivision, more famously known as Sand Patch Grade. Here are a couple of suggestions for the best Scenarios and Services that will help you hone your newly-found skills!
Scenarios: A Helping Hand, Powering America (Part 2)
Services: (SD40-2) U876-C – Coal – Shaw Mine to Yoder Siding
Let us know how you get on by commenting below, do you have any tips or tricks for learning signalling systems? You can see below a few examples of the signals found on the Sand Patch Grade route, which is authentically recreated in and ready for service in Train Sim World: CSX Heavy Haul, find out more here ■
DigitalDraftsman shared some additional information with us that might also be useful: