Part V: Why is it important for Europe to agree on a design for the Digital Automatic Coupler?

02. 08. 2021

The Digital Automatic Coupler is a milestone in making rail freight in Europe more competitive: it makes coupling not only easier and safer, but also more efficient.

We have answered the most important questions about the next steps for the introduction of DAC in the fifth part of our series.

Why is it important for Europe to agree on a design for the DAC?

There can only be one standard coupling head including standard interfaces for power and data in Europe because different coupling heads are not compatible with each other. Different coupling heads were tested in the process. The decision for a coupler head will be made on the basis of different criteria, the evaluation of concepts and life cycle analyses and will finally be decided on a European level within the framework of the Shift2Rail-European DAC Delivery Programme.

When will the digital automatic coupling be released?

By 2030, the majority of European wagons will be equipped with DAC4. The Digital Automatic Coupling is a milestone towards making rail freight transport in Europe more competitive: DAC not only makes coupling easier and safer, but also more efficient. Europe is the last continent not yet using an automatic coupling system. With the introduction in 2030, however, it is set to become the first continent with a Digital Automatic Coupling System.

How can DAC and screw coupling be combined in the transition phase?

During the transition period, rail freight traffic will have to continue in mixed operation. This can be done with various strategies. For example, some wagons can be equipped with a hybrid coupling or certain wagons can serve as coupling wagons, which are equipped with a screw coupling on one side and a DAC on the other. The exact form mixed operation will take is still being evaluated.

How does the European DAC Delivery Programme operate?

The European DAC Delivery Programme (EDDP) facilitated by Shift2Rail is a unique platform dedicated to the successful implementation of Digital Automatic Coupling (DAC) revolutionising rail freight in Europe. The project is built on an open cooperation concept and brings together a wide range of organisations from railway undertakings, infrastructure operators and wagon owners as well as the railway supply industry, maintenance organisations, affected industry organisations, railway research institutions and national and European governance institutions. The aim is to provide a European DAC solution through an integrated joint programme, based on R&I findings and pilot projects, ensuring the necessary actions for a fast, technically and economically feasible implementation across Europe.

The DAC4EU consortium, consisting of the consortium leader DB AG, the ÖBB Rail Cargo Group, DB Cargo and SBB Cargo freight railways and the wagon owners Ermewa, GATX Rail Europe and VTG, has been entrusted by the German Federal Ministry of Transport and Digital Infrastructure (BMVI) with the testing of several prototypes of digital automatic couplers from a variety of manufacturers. The consortium's test results will be used in the selection decision regarding a standardised coupling type across Europe, by the EDDP. The consortium started its work in June 2020. The German Federal Ministry of Transport and Digital Infrastructure (BMVI) is financing the project for the duration of two and a half years by providing around 13 million euros. By 2030, trains throughout Europe should be equipped with the new technology and contribute to rail freight traffic playing an essential role in the European mobility system of the future.
For more information visit

The Federal Ministry for Climate Protection, Environment, Energy, Mobility, Innovation and Technology (BMK) is funding project TARO, which also covers DAC topics, with a total of 3.5 million euros from the RTI programme Mobility of the Future, run by the Austrian Society for the Promotion of Research (FFG).