Railway Signalling in Bayland

Multiple types of railway signalling are used in Bayland, the most common being the Bayrail in-cab signalling (BRIC) system. Other systems include semaphores, modern light signals, and Swedish light signals.
== BRIC ==
BRIC is an in-cab signalling system used by Bayrail. It is similar to ETCS however it is not compatible. The most common version of BRIC is BRIC2. Common attributes for all BRIC versions include most cab equipment and BRIC boards (although the appearance varies).
=== BRIC1 ===
The first version of BRIC to be developed is called BRIC1 and continues to be used on some lines. It was first installed in 2001 and operations started in 2002. Lineside signals are still used with BRIC1, partially as a fallback measure, but mainly to allow rolling stock without BRIC equipment to operate during the transition period to BRIC. BRIC1 allowed 225km/h operation for the first time in Bayland, an improvement from the previous 180km/h.
=== BRIC2 ===
BRIC2 is the most common version of BRIC, and the first version to not have any lineside signals. It is similar to BRIC1, with minor technical improvements. It was first installed on the Norsham Line in 2009 with operations starting in 2010. Additional improvements along with BRIC2 also allowed the top speed of the Baylandese railway network to be increased to 250km/h.
=== BRIC3 ===
BRIC3 introduces major technical improvements, such as combining radio and balise indications to allow for limited moving block capability. It was first installed on the Ferúqo Branchline in Kwitzka in 2014 and begun operation the same year. BRIC3 also allows for 300km/h running, although this speed is currently not allowed on any railway using BRIC.
=== eBRIC ===
eBRIC is based on BRIC3 and is a simpler system using only radio and moving blocks. It is very cheap to install but has limited fallback capabilities, unless existing lineside signals are kept. It is mainly intended for less used regional lines and local freight lines. eBRIC lines are limited to a speed of 160km/h. eBRIC was first installed on the Borderside Line in 2018 and eBRIC operations begun the same year.
=== BRIC4 ===
BRIC4 is the newest BRIC version, being first installed in 2022, and operations beginning in 2023. It is similar to BRIC3 but allows trains to run entirely on radio indications. BRIC4 has seen limited installations on the Bleckmouth and Bleckbridge lines. BRIC4 is also easily upgradable to allow for BRIC ATO.
=== BRIC ATO (BRIC 3,5/4,5) ===
BRIC ATO is an Automatic Train Operation (ATO) system based on BRIC4 or BRIC3. It is currently undergoing testing in Kwitzka. It will allow for trains to run either entirely without a driver, or with a driver present but with no driver intervention. It is expected that most lines in Bayland, especially urban lines, will be upgraded to BRIC ATO to allow for more efficient running.
== Colorlight Signalling ==
Note that the Beachport Southwestern Railway uses Swedish colorlight signalling, which is a separate system.
The main Baylandese standard for colorlight signalling was created in 1942 to replace the semaphore signals, and to provide more detailed signal aspects. It has since been widely implemented, although since the year 2000 it has been mostly replaced by BRIC.
=== Aspects ===
* Single red: Stop
* Single solid green: Proceed 80km/h
* Double solid green: Proceed line speed
* Solid green+solid white: Proceed 100km/h
* Single solid white: Proceed 40km/h
* Solid white+solid yellow: Proceed 60km/h
* Single solid yellow: Proceed at a speed where the train can be stopped in half of the sight distance
Yellow bar+red+regular aspect is a shunting aspect and allows shunting at the speed of the regular aspect, with a solid yellow+red+yellow bar being used for shunting into occupied tracks.
This colorlight signalling system is in some cases used in conjunction with BRIC, where a BRIC board is also placed next to the signal.
== Early Signals ==
Private railway companies were initially free to adopt their own signalling, with many different signalling systems being used. Interoperability was rarely considered as different railway companies operated exclusively in their own territory until the 1890s when the first trains across multiple railways started operating. Signalling systems from this period include token signalling and both lower and upper quadrant semaphores.
== SR Semaphores ==
In 1897, four railways (the Newcoast and Blymouth, the Ely and Blymouth, the Ely and Wyndham, and the Wyndham and Newston) made an agreement to cooperate on a unified signalling system, using upper quadrant semaphore signals. It was this system that was later adopted by the SR (now Bayrail) in 1903. This system continues to be used on heritage railways, but all Bayrail-owned lines now use more modern signalling.
== Signal Boxes ==
Traditionally, each station would have a signal box where the signals for that station is controlled, and the lines to adjacent stations are jointly controlled by the 2 signal boxes. This is now rare in Bayland, with only a few railways using this arrangement on short sections. Most lines in Bayland are controlled by a Remote Signalling Center (RSC). These are located at major stations, for example, the Beachport area is controlled by the Beachport RSC, which is located at Beachport Central. Some RSCs are also split into dispatching areas, which are signalled separately, but from the same location.
=== Equipment ===
Before colorlight signals were introduced in the 1940s, almost all signals and switches were controlled by levers in signal boxes. This was the main reason for the signal boxes being placed at each station. After colorlight signals were widely implemented, more modern electronic control systems, with the first systems consisting of an array of buttons and lights. Track circuits were introduced in 1952 and were mandated on every railway line with a line speed above 70km/h in 1963. This meant signallers could now accurately track the position of trains, allowing for the outdated practice of writing down each train movement in a book to end.
The current signal control system on most mainlines in Bayland was introduced in 2009, at the same time as BRIC version 2. It uses computer input to manage trains, being the first system to do so. It is expected to be replaced by a newer system in 2024, as this system is already in development.