autopilot, automatically driving at the maximum speed currently allowed by LZB signalling. In this mode, the driver only monitors the train and watches for unexpected obstacles on the tracks. On lines equipped with only PZB/Indusi, AFB acts entirely as a speed cruise control, driving according to the speed set by the driver with manual braking if needed. CR400BF-C 'Fuxing Hao', a variant of CR400 Fuxing series, running on Beijing–Zhangjiakou intercity railway is said to be the world first high-speed rail service capable of driverless automation in commercial operations. The specific Grade of Automation (GoA) was not announced. Operation of ATO Whereas ATP is the safety system that ensures a safe spacing between trains and provides sufficient warning as to when to stop. ATO is the "non-safety" part of train operation related to station stops and starts, and indicates the stopping position for the train once the ATP has confirmed that the line is clear. The train approaches the station under clear signals, so it can do a normal run-in. When it reaches the first beacon – originally a looped cable, now usually a fixed transponder – a station brake command is received by the train. The on-board computer calculates the braking curve to enable it to stop at the correct point, and as the train runs in towards the platform, the curve is updated a number of times (which varies from system to system) to ensure accuracy. When the train has stopped, it verifies that its brakes are applied and checks that it has stopped within the door-enabling loops. These loops verify the position of the train relative to the platform and which side the doors should open. Once all this is complete, the ATO will open the doors. After a set time, predetermined or varied by the control centre as required, the ATO will close the doors and automatically restart the train if the door closed proving circuit is complete. Some systems have platform screen doors as well. ATO will also provide a signal for these to open once it has completed the on-board checking procedure. Although described here as an ATO function, door enabling at stations is often incorporated as part of the ATP equipment because it is regarded as a "vital" system and requires the same safety validation processes as ATP. Once door operation is completed, ATO will accelerate the train to its cruising speed, allow it