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I was wondering if anyone had an example of a ticket that might be used in a time interval signalling system? I'm reading up on Armagh and the report mentions a ticket. Just curious.
Not really IRSE exams but any pointers anyone?
Thanks in advance
(18-05-2014, 03:07 PM)Motty Wrote: [ -> ]I was wondering if anyone had an example of a ticket that might be used in a time interval signalling system? I'm reading up on Armagh and the report mentions a ticket. Just curious.
Not really IRSE exams but any pointers anyone?
Thanks in advance

I'll try to look out a photo of something, perhaps over next weekend as busy for next few evenings.
Ticket working is only really used in UK nowadays when things have failed or other major disruption; sometimes Temporary Block Working is instituted as part of planned work during resignallings for example, There is a very good Virgin Trains video that shows a reconstruction of when it introduced in failure scenario and the driver mislays the ticket listing the IDs of the signals authorised to be paseds at danger and goes one too far to suddenly encounter at speed a handsignaller with red flag and detomnators on the track and says something meaning "Dash it, what a shame I appear to have gone too far" but uses pretty basic railway language.

Ticket working on single lines is rarer; generally a pilotman is appointed. However I am pretty sure that "staff and ticket" is still used for unusual service patterns on some heritage railways- I certainly have a photo of the ticket for a section on the Mid Hants. Of course some such lines are operated almost entirely procedurally using train graphs and radio communication etc.

However none of the above are "time interval" working; the section is always established to be clear by some method (e.g. the handsignaller at the exit of the section observing the train has passed complete with tail lamp). Time interval only has to be resorted to when there is no communication at all from end to end; nowadays this would be so extremely rare that it is exceptionally unlikely and so not an eventuality which has to be catered for in the rules. A hundred years ago though, it was not so unlikely and therefore the only way to run trains at all when such did occur that just had to get the 2nd train to wait for a long time and then let it proceed cautiously and hope that it did not encounter the previous one.

The last time that I recall something like (but not exactly) that happening was on the Chilterns at Seer Green when the snow was heavy.
First train had to stop when the line was blocked and disrupted communication. The second was despatched not having given the first much of a head start and was proceeding rather too fast and ran into the back of the first- think I had just started on the railway then, I could check the history books / Google it but must have been about 1981/2.
Unfortunately I don't have my books available at the moment (packed; expecting to move house) but I think Armargh disaster occurred under time interval working. One of the many incidents that fuelled the call for "Lock, block and brake". Looking at Wikipedia I think the only tickets involved would have been those of the passengers.
some of the accounts talk about the station master recording the late departure time on a ticket.
It might just be a figure of speech, but I imagine the departure time was recorded in an occurrence book or contemporary equivalent?