If the ATC mode switch is in MATC position when entering Yard territory, what happens?

When the ATC (Automatic Train Control) mode switch is in the MATC (Manual Automatic Train Control) position while entering Yard territory, the train is designed to safely manage its speed and operations in adherence to the rules governing Yard areas. Specifically, one of the primary safety functions of the ATC system is to ensure that trains are controlled appropriately when transitioning between operational areas, particularly when moving from high-speed mainline services to slower yard operations where caution is paramount.

In this scenario, the system is programmed to stop the train before it leaves the mainline, ensuring that it enters the yard safely without exceeding speed limits and without endangering the safety of personnel or other equipment within the Yard territory. This feature helps prevent accidents that may occur due to excessive speed or unforeseen obstacles in the Yard, which typically has different operational protocols compared to the mainline.

Therefore, the correct answer reflects the proactive safety measures integrated into the ATC system that prioritize the safe operation of trains when entering areas where there is a need for lower speed and increased caution.