photo: RAILTARGET Archive/The DAC Project Unveils New Issues Not Previously Discussed in the European DAC Delivery Team
The Digital Automatic Coupling (DAC) project has revealed new issues that the European DAC Delivery Program (EDDP) team had not previously addressed. In video presentations, the team from Europe's Rail and Deutsche Bahn explained their approach to retrofitting technology. The data, provided by Deutsche Bahn, considered factors such as each locomotive type's significance, its fleet proportion, its age, its remaining service life, and parameters that qualify it for retrofitting or otherwise mark it for retirement.
During this process, Deutsche Bahn realized that it lacked the necessary information from the locomotive manufacturers for some types. Locomotives with sufficient information were grouped based on various criteria, including the frame's ability to absorb DAC forces, crashworthiness, potential DAC design solutions, DAC power supply, and the feasibility of integrating the digital component of the DAC. They also considered the locomotive's ability to handle added weight and its axle load or structural strength.
Germany's premier rail operator acknowledged the challenge of obtaining manufacturer support for older locomotives. Interestingly, they found that newer locomotives posed greater difficulties for DAC adapter installations due to EN 15227 limitations. These locomotives aren't designed for DAC forces which act along the axis of the train. Another issue is the increase in overall weight, particularly with newer models. Hence, there's no one-size-fits-all solution for DAC retrofitting on locomotives. Europe's Rail plans to organize a workshop with locomotive and coupling manufacturers later this year.
By October 2023, Europe's Rail intends to request European carriers to assess their fleets' DAC readiness under the HORIZON-ER-JU-2023-EXPLR-06 program. Data from each member state will feed into a centralized "DAC Cloud" database.
Around 400 different types of vehicles are currently in operation in Europe. Of these, DB has tested 181 types and found that 69 can be retrofitted without modifications, 80 types require different documentation, 8 types need retrofitting before DAC can be added, and 24 types will need to be taken out of service. The DAC-Cloud will be fully funded by Europe's Rail and will include a public section and a section only accessible to vehicle holders. The public section will be for registering all vehicle types and will contain technical information on the DAC. The private section will allow vehicle holders to share information on specific vehicle types. This database will help EDDP analyze the current state of vehicles in Europe and will serve as an economic analysis of the DAC deployment project.
There is a renewed discussion about real-life testing. Unlike previous "demonstration" events, this testing should encompass genuine parameters. These include interoperability, DAC upgrade capability to level 5 (full digitalisation), automatic brake tests, train integrity tests, and automatic train shifting. Additionally, parameters such as parking brake control, autonomous shunting operations, and dispatching will be considered. The testing will also evaluate multi-source data transfer functionality, interoperability in cross-border traffic, the application of DAC data for timetable planning, dynamic logistics management, intermodal connectivity, and DAC's potential to incorporate artificial intelligence features. Furthermore, the procedures of test facilities and their approval processes in relation to DAC will be assessed.
Europe's Rail has recently begun addressing the issue of vehicle approval, a move prompted by numerous challenges posed by carriers. Below is a diagram depicting DAC approval at the mechanical coupling level.
The subsequent diagram illustrates the proposed approval procedure for DAC, encompassing full digitisation and automation.
The approval of electromagnetic compatibility solutions is still a pressing matter, as different national technical regulations exist. The goal is to ensure that no further approvals are necessary. Harmonizing the EMC requirements (TSI CCS) is proving complicated in the working group, which includes a Czech representative. Since this isn't a railway standard but an electrical one, future DAC TSIs will likely only reference this new standard.
It's positive that the approach of the European institution responsible for the Digital Automatic Coupling project has evolved. New areas are emerging where significant work remains, and all elements of the DAC need to be tested technically and according to parameters vital for the carriers. This means assessing how rail freight companies' new management will need to be structured, which activities will need training or retraining, and what the financial implications of DAC implementation will be.