Specification issues report on subset 26 - 5.9.1.1

[Farhangi]

Description:

The ERTMS/ETCS on-board equipment shall be in On Sight mode before the train reaches the beginning of the On Sight area or, at the latest, when the train reaches the beginning of the On Sight area.

Comment:

According to the Condition 73 of the Chapter 4.6, needed to pass from LS mode to OS mode, the transition can be performed only if (1) the max safe front end of the train is inside the On Sight area AND (2) the estimated front end of the train is not inside an LS acknowledgement area. So, in this particular case, if the condition (2) is satisfied, the train shall not pass in On Sight when it reaches the beginning of the On Sight area. Also, if the level is 0 or NTC, the train will not pass in On Sight (see Paragraph 5.9.4.1).