13-09-2017, 07:21 PM
(This post was last modified: 13-09-2017, 07:35 PM by mattslade222.)
Hi,
I have been talking this question through with my sponsor and on reflection feel like I may have made a complete hash of it! My attempt is attached below.
I'm not looking for a full critique but a pointer in relation to parts A and B, whether I have interpreted the question correctly.
I read A as why can a train protection not always stop a train at a restrictive signal. So in the case of TPWS it doesn't know a SPAD is going to happen until it actually happens, OSS improves on this but its not fool proof. Continuous ATP goes along way to improve, however, it still cannot account for some aspects. Or even something like the signal being reverted at the last minute.
Questions B i read as, once a trigger of the system has occurred why may the train not be stopped prior to the overlap at fouling point.
Thanks for any responses.
I have been talking this question through with my sponsor and on reflection feel like I may have made a complete hash of it! My attempt is attached below.
I'm not looking for a full critique but a pointer in relation to parts A and B, whether I have interpreted the question correctly.
I read A as why can a train protection not always stop a train at a restrictive signal. So in the case of TPWS it doesn't know a SPAD is going to happen until it actually happens, OSS improves on this but its not fool proof. Continuous ATP goes along way to improve, however, it still cannot account for some aspects. Or even something like the signal being reverted at the last minute.
Questions B i read as, once a trigger of the system has occurred why may the train not be stopped prior to the overlap at fouling point.
Thanks for any responses.