ATP Failure (Central)

That makes good sense to me, it would just seem a little redundant in that case to bother with the running signals in the first place. The idea behind the white and green aspects is that you only get a green if the track is clear up to the next signal, then you can proceed in RM. You can't proceed in RM on a white because there is a train between you and the next signal but it's not in the next block and the Maximum Safe Speed is more than 0, i.e. you have clear codes so you can proceed in Coded or Auto because the ATP will keep you a safe distance apart. Whereas when operating only on colour light signals, as in a conventional railway, you only have the signals to keep trains a safe distant apart. But you do have the signals. In the case of the one that went defective at Leyton the failure was local to the train, the signalling system was fine, so I'm not sure it's really the same as stop and proceed, because you know there isn't gonna be anything bad between you and the next signal. Of course, there's no protection against SPADs, but surely if the track must be clear to get the green, it doesn't make sense to force the train to be driven as if there was no way of knowing whether the block ahead was occupied or not (which is the situation you have with stop and proceed), because you do know there's no train ahead.

I suppose I was just wondering what the logic is, really, behind having running signals in this case. I understood, well, like I said above that RM is for degraded working and you have white signals which you can't pass in RM because there's a train ahead and you won't know where it is so you might hit it. But once you've got the green, why limit the train to 16 kph when you know full well the track ahead is clear, surely it's no less safe that BR signalling before TPWS? Admittedly BR signals had AWS but the point is, though there's no protection against SPADs, the trains would be safely separated by the Central line's running signals, just like a conventional railway. They're often very far apart, but I just...I couldn't explain to my mother why the 16 kph limit was necessary when you've got a signal there telling you that the track ahead is clear.

I think you're probably spot on regarding trainstops though. And thanks I hope I didn't appear dismissive, I think you raised some very good points, I just wonder why the powers that be didn't include any kind of intermediate between Restricted Manual and Coded/Auto for situations like these, or else, why even bother with running signals?