Help with three letter acronyms

[dave1]

I have been doing some research and have come across some of those three letter acronyms and wonder if any can help clarify exactly what they mean as both have been used in failures of signals. 

RAD-Remaining at danger
FTC-Failing to clear

To me both mean the same just expressed a different way, Which one should be used and when.


TIA

[Nortube]

Both phrases also used in the past tense

From a driver's point of view, I would assume that Remaining at Danger would normally be used for where the signal was deliberately held at danger (by the signalman etc.)
e.g. the signal was Remaining At Danger because there was a train ahead


Whereas Failing To Clear would be used more specifically as a failure - i.e. the signal didn't clear when it was supposed to because of a mechanical / electrical etc. fault
e.g. the signal was Failing To Clear because of a blown track fuse


It's quite possible that the explanations would overlap and RAD and FTC used for the same thing, depending on who is writing the report and in what circumstances
e.g.
The driver spadded the signal because it Remained At Danger as the train approached it
The driver spadded the signal because it Failed To Clear as the train approached it

could both refer to the driver spadding a semi-automatic signal that would normally clear by the time the train reached it, but in this case it remained at danger - perhaps due a train going over a junction ahead.

 

[dave1]

I came to the same conclusion after working it out but I did think perhaps RAD was used when a signal could not clear and FTC was used when a signal did not clear after operating a circuit of some sort.

[railtechnician]

I would contend that there is a difference although in the great scheme of things it wouldn't matter too much although in a report the proper inference should always be made particularly in the case of a signalling failure.

A signal could 'remain at danger' for many reasons both legitimate and illegitimate whereas a signal 'failing to clear' infers a failure of some kind. The difference is subtle but there clearly is a difference.