Quintinshill - Signalling

[ChrisPSR]

What is "cleared away", please? The Up Main Home and the Up Distant must have been 'on' (danger/caution) whilst the coal empties were being admitted to the loop - the mechanical interlocking, by then a fundamental part of any signalling installation, would have prevented that. The Up Loop Home signal (which had authorised that movement) must have been replaced to danger before the loop entry points were returned to normal, and at some time after that, the signals right through on the Up Main were cleared (that is, to show a proceed indication). Do you disagree with any of that?

1) Do not the words used indicate the meaning?
2) I think you should have been at the various hearings if you know how the signals were operated and engineered. I have certainly not read any definitive proof of your engineering and use statements. All engineering was in its infancy fitted in part through to none existent.

 

[MarkyT]

Assume the down local is stood on the up main and the empty coal is safely within the loop with its guard's confirmation that it had arrived complete. It appears then there still wasn't a clear block overlap from up home to the clearance point whichever way the loop points were set, so In that case perhaps a 'train out of section' message should not have been sent to the rear box at all. Instead 'blocking back' would have been the appropriate code, in the absence of a specific block telegraph TOL indication, effectively to explain and remind why a train out of section could not be sent. Did the rules of the day require a TOS code followed immediately by a BB in such a circumstance?

 

[Clarence Yard]

Yes, the Caledonian instruction of the day said you gave TOS first and then gave 2 - 4 to block back.

I had a play with a Caledonian block today, funnily enough, and in my previous post I said I would have used the tapper to block back. Wrong! Teach me to post late at night! The regulations state you use the upper (red) plunger (or key as it is sometimes called), which is more logical when you think about it. The box in rear uses his tapper (or ringing key as it also known) to acknowledge.

The important point, which is in the regulations and in my previous post, is that you do not push the brass button plunger on the left hand side of the instrument in. As well as keeping the on line indicator "on" that locks the white plunger and therefore you cannot accept another train from the box in rear.

What the regulations are a little vague on is the situation where the obstruction is already there when you give T.O.S. and swinging the loop points back to normal. They were written on he assumption that the obstruction would be created after 2 - 4 is sent and acknowledged. But the first paragraph of the instruction (13a) is written in such general terms that the principle of T.O.S. and then block back before you can accept another train is firmly established.

 

[cjmillsnun]

Hi Can you give me any links to this program such as Title, channel and the length of time ago it was aired as I would like to know whether its available say on iPlayer or some other catch up channel/program.

Thanks for the input,
Chris S.

http://www.bbc.co.uk/iplayer/episode/b05vqx7v/britains-deadliest-rail-disaster-quintinshill

 

[Tomnick]

1) Do not the words used indicate the meaning?
2) I think you should have been at the various hearings if you know how the signals were operated and engineered. I have certainly not read any definitive proof of your engineering and use statements. All engineering was in its infancy fitted in part through to none existent.

1. No, it isn't a signalling term that I've ever encountered. Do you mean 'returned to danger'? Quite the opposite of 'cleared'.

2. Mechnical interlocking between points and signals was very well established by that time, and was a fundamental principle of any signalling installation (leaving side light railways, tramways and the like). Any fault there would have been very much worthy of note in the accident return, but - above all else - if the Up Distant and Up Home had been 'off', I rather suspect that the driver of the coal empties would have had something to say about it too! It seems entirely unbelievable to me, and I don't really understand how you're suggesting it would've changed the attribution of blame in any way.

 

[matchmaker]

Mechnical interlocking between points and signals was very well established by that time, and was a fundamental principle of any signalling installation (leaving side light railways, tramways and the like). Any fault there would have been very much worthy of note in the accident return, but - above all else - if the Up Distant and Up Home had been 'off', I rather suspect that the driver of the coal empties would have had something to say about it too! It seems entirely unbelievable to me, and I don't really understand how you're suggesting it would've changed the attribution of blame in any way.

Indeed. Made a legal requirement by section 1 of The Regulation of Railways Act, 1889.