Explained – the difference between DAS and C-DAS

Imagine a network where your trains run in a state of dependable efficiency.

On this network, each train is controlled by a driver using in-cab advice tailored to their specific route and consist. The synchronised combination of skilled operators and supportive technology guides each train towards achieving peak performance.

Timetables are safely adhered to, greater fuel efficiency is achieved, and your entire team’s stress levels are reduced, from drivers to the C-suite. This is the Trapeze Rail Driving Advice System, usually referred to as DAS, in action.

Now consider a situation where these trains can also communicate with one another in real time, via an external network such as your Traffic Management System (TMS). Every train is connected and engaged in a ceaseless, software-powered conversation that shares the position of all the other trains.

By constantly understanding their movements, these connected trains are aligned and can function together. Opportunities for moving large amounts of traffic through the network’s most complex locations now become much more sophisticated. This second outcome is the Connected Driving Advice System, known as C-DAS.

While simplified scenarios don’t tell the entire story, they do offer a convenient point of entry to understand the essential differences between Trapeze’s DAS and C-DAS solutions.

Every driver can achieve the golden run

The guiding principle powering DAS is to provide real-time advice for driving any type of train, based upon the optimal journey profile – the ‘golden run’.

This advice is designed to keep your trains running on time, save fuel costs, and protect your assets by minimising wasted energy caused by unnecessary braking and acceleration. The more closely drivers follow the advice, the more efficient the journey becomes. Your operation is now more likely to meet schedules, reduce energy expenditure – whether diesel or electric – and deliver your sustainability targets by decreasing carbon emissions.

C-DAS builds upon the core DAS platform by adding an enhanced level of connectivity. Your business retains all the benefits of DAS and creates new possibilities for greater network capacity, business intelligence, decarbonisation, and energy savings.

The C-DAS technology seamlessly connects with your existing signalling and TMS, including ATMS and PTC, that underpin the efficiency and safety of rail operations. It can also connect with other software such as planning and scheduling systems and workforce management solutions.

Integration with your real-time information allows the software to consider all aspects of your schedule, including the live information provided by each train movement. The entire network can be managed to ensure conditions, conflicts or adjustments are applied to every train, supporting synchronised and efficient operations.

The solution responds proactively to congestion, temporary speed restrictions or any other unexpected event. Your drivers are assisted with making up lost time safely and efficiently through real-time adjustments to their optimal journey profile.

Complex junctions and congested networks

DAS and C-DAS are recognised as transformative solutions for the global rail industry because they support a range of high-value performance, profitability, and decarbonisation outcomes simultaneously.

One of the significant benefits of C-DAS is its optimal management of train movements through critical timing points using its Junction Scheduler functionality. The technology constantly re-plans connected train movements through these locations to minimise delays at an individual junction, or a network of junctions. It does this by resolving conflicts in real-time, while also considering energy use.

Each train is automatically monitored to determine its achievable arrival time. Junction occupancy intervals are allocated to ensure approaching trains are spaced with appropriate headways. The revised arrival times are calculated, and the in-cab advice to drivers is updated accordingly.

Increased on-time running at complex junctions significantly improves performance and capacity for congested networks, as well as providing greater benefits in fuel costs and asset management.

This is especially desirable in regions with a mix of passenger and freight services, and where late running can incur expensive financial penalties, such as in the UK’s highly congested rail system. Delay minutes realised by Junction Scheduler can result in savings for UK rail operators by reducing Infrastructure Manager imposed delay penalties.

First Group, which delivers around 27% of the UK rail market, is partnering with Trapeze Rail on a comprehensive C-DAS trial along routes operated by Great Western Railway. Reporting on the trial is expected to endorse C-DAS for the UK rail industry.

Junction Scheduler was previously implemented at a location close to London’s Heathrow Airport, where data showed that a staggering 75% of delays could be avoided using the technology.

Business intelligence for progressive operators

C-DAS users can expect greater network insights through increased business intelligence capabilities, as the technology generates precise train running data that supports timetable performance analysis, improvements, and reporting.

These business intelligence benefits include calculating savings based on train stoppage reductions and having accurate data to consider cost delays, fines and other KPIs. Installing DAS or C-DAS is an entry point for progressive rail businesses that want to improve efficiency, accelerate their decarbonisation efforts, and reduce fuel costs as part of their digital transformation.

To help organisations like yours understand the value of this technology, the Trapeze Rail team’s industry experts are available to answer questions, discuss opportunities and assess the possible benefits to your business.

Want to know more? It’s time to get in touch, and we also suggest you read our blog which provides an introduction to the core DAS solution.


Connected-DAS: A Revolution in Driver Advisory Systems

Find out the benefits of Connected-DAS which can be magnified by integrating it with a Traffic Management System.

Learn more

Mode of Transport



Driving Advice System (DAS)

Meet the author

Trapeze Group

Contact us

Group 17 Copy