The head code system for locomotives on the UK rail network was a way of indicating the type of train and its route to signalmen and other railway workers. The head code was displayed on a board or a panel at the front of the locomotive, and it consisted of four letters and numbers.
Four Character System
The first two characters indicated the type of train, such as “1A” for express passenger services or “4F” for freight services. The third character indicated the route, and the fourth character indicated the class of the train.
The head code system was phased out in the 1980s and 1990s as newer signalling systems were introduced. Today, locomotives on the UK rail network use a range of modern signalling and identification systems, including Automatic Train Protection (ATP) and Train Management and Control Systems (TMCS), which use digital displays and communications technology to provide real-time information to train drivers and control centres.
ATP System
Automatic Train Protection (ATP) is a safety system used on railways to prevent collisions, derailments, and other accidents. It works by constantly monitoring the speed and position of trains and enforcing speed restrictions and other safety rules.
ATP systems use a combination of on-board equipment and trackside infrastructure, such as signals and track circuits, to communicate information to the train driver and automatically control the train’s speed and braking if necessary.
There are several different types of ATP systems in use around the world, including legacy analog systems and newer digital systems. Some ATP systems can also provide additional features such as train positioning, remote control of points and signals, and advanced train management capabilities.
TMCS (Train Management and Control System)
TMCS stands for Train Management and Control System, which is a software-based system used by railways to manage and control train operations.
The TMCS typically includes a variety of functions, such as train dispatching, train tracking and monitoring, crew management, and resource allocation. It allows railway operators to optimize their operations and improve efficiency by providing real-time information on train movements, schedules, and other key operational data.
The TMCS also helps to ensure the safety of train operations by monitoring trains and their movements, and providing alerts and warnings to train dispatchers and other personnel in the event of potential safety issues or operational problems.
TMCS is an important tool for railway operators in managing and controlling their operations, improving efficiency, and ensuring the safety of train movements.
How to Identify Trains without Head Codes
Trainspotters can use several other methods to identify trains, such as:
- Livery: The color scheme and design of a train’s exterior can often indicate which company or operator it belongs to.
- Numbering and Naming: Trains are often identified by a unique alphanumeric number, which can be used to determine the type of train and its origin and destination. Some trains also have names or designations that can be used to identify them.
- Rolling Stock: Different types of trains have distinct shapes, sizes, and designs. Trainspotters can learn to recognize the differences between locomotives, passenger cars, and freight cars, as well as the variations within each category.
- Route and Schedule: Knowing the typical routes and schedules of trains can help trainspotters anticipate when and where certain trains are likely to pass by.
- Radio Communications: Trainspotters who have access to radio scanners can listen in on the communications between train crews and dispatchers, which can provide additional information about the identity and location of trains.
The TBRD Headcode
The TBRD headcode was a train reporting number system used by British Rail to identify and track trains on the rail network. It stood for Train Booked Running Days and was a four-digit number that identified a specific train service. The first two digits represented the day of the week on which the train was scheduled to run (00 for Sunday, 01 for Monday, and so on), while the last two digits represented the train’s number within that day’s schedule. The TBRD headcode system was used from the 1960s until the 1980s, when it was replaced by a new system that used computerized train reporting codes.