14 Bombardier Transportation is responsible for manufacture of the trains and developing the onboard software and systems to operate them. Siemens is responsible for installation and software development of lineside signalling systems in the central section.
15 Development of the software and on-board signalling systems required to operate the trains has been significantly delayed. In July 2017, Crossrail Ltd raised an Adverse Event Notice to the sponsors, stating that the opening of services on the western section (stage 2) and the central section (stage 3) were at risk. There have also been delays to testing of the train due to delays to the installation of signalling equipment in the tunnels and station in the central section.
16 Delays were made worse in October 2017, when a transformer connection failed, meaning that the central tunnel could not be electrified as planned. This delayed the start of dynamic testing of the train with the signalling system by three months and presented a significant problem for the schedule, as this signalling integration testing was essential for the central section opening in December 2018. Unlike the station and system implementation contracts, the delays to the development of the train had little direct impact on the cost of the programme because Transport for London had signed a contract with Bombardier Transportation for a fixed price of around £1 billion, and the cost of the trains and depot are accounted for outside the programme budget for Crossrail.
17 The accumulated schedule pressure from the infrastructure delays, and the delayed start to dynamic testing, meant that by early 2018 there was little time remaining to carry all the testing required to gain the required assurance that services could be operated safely and effectively. In order to meet the December 2018 opening date for the central section, Crossrail Ltd planned to carry out both construction and dynamic testing in parallel. Crossrail Ltd did this to ensure that any early issues with the train and signalling software could be found and resolved. However, because the train and signalling software had not been developed to the required level, this testing proved to be of limited use. It also added to the compression in the programme as testing took up spare time and space on the Crossrail station and tunnel sites, which could have been used to make progress with construction and installation of systems.