![]() I figured it out from the Swindon S&T parts catalogue that this stubby arm used the "SB" (Special Boss) arm of the SB signal - commonly called a "Centre Balanced" arm by enthusiasts. The GWR did a very nice/weird repeater arm. It is possible that a bracketed and high main signal would have a repeater arm on the main post. Bracketing the senior signal up and to the right would make a good differentiation between the two signals and create good sighting for higher speed on the main. (In fact going over the lesser line might mean a small gantry across all lines). This is less of a structural issue than bracketing over the lesser line. one option would be to put the lesser signal on a straight post on the left of its line with the arm at 12 to 15 feet above rail head.and then bracket the senior signal out over the centre line of the senior line with its main post between the two lines. I'm assuming that the OP knows that a signal for a lesser line will be lower in height than the adjacent signal for a senior line. As an alternative one, usually on the lesser line, may be pushed back to the rear ("on the approach to"). Generally this assists sighting and minimises risk of confusion. "Normally" signals (ie running signals) on adjacent lines are located on or close to a line perpendicular across the tracks. bridges and a whole load more - including risk of smoke from factories) and - eventually - track layout. The siting of a signal (and adjacent signals) - that is the location of it - is a direct result of the sighting requirements - which are determined by curvature, gradient, line speed, environmental conditions (eg structures, embankments/cuttings. This particularly applied to signals out of bay platforms. However, this would more than likely be a single doll bracket - and the left hand line's signal would be on a separate post (which would stand on the approach side of the brackets structure - possibly set some way back.īrackets for the same direction on island and other double sided platforms - this was not so much to save space (fit into space) but so that the guard when on the platform and platform staff could see the signal - which might otherwise be hidden by the train. The main post of this bracket would be on the left of the left hand line. this would be where available space caused the signal for the right hand line to be bracketed out over the left hand line so that the doll, arm and light got into the location it would be in if a post could be fitted in on the left of the right hand line. There is a slight case for a bracket signal though. However, this said - the signal would normally be to the left of the line it applied to. Something to keep in mind is that train speeds, especially unfitted freights, were much slower. Kind of persuasive to not getting the job wrong. ![]() They could, of course, also lose their lives - and some of the ways train crew lost their lives were excruciating - cooked by being buried by the coal from their tender igniting with the coal in the firebox. If an over-run occurred all the crew could lose their jobs immediately. Train crews were expected/required to have their trains under control. Unlike todays "defensive" thinking where an overlap will be included between the signal and the fouling point wherever possible the older thinking was that train crews were instructed to stop dead in rear of a stop signal that was against them ("on"). Semaphore signals protecting any convergence - even on fast lines - could be located right up to about a yard in rear of the fouling point. This protecting by a signal in rear could be shuffled along the station limits so that a home protected a starter and a starter protected an advanced starter - although the last is the least likely. If there was even the slightest risk of a signal being misread it would not be allowed wrong side - where necessary the signal would be right side with a bad sighting which was compensated for by a banner repeater - and, in an extreme case, by a severe speed restriction on the approach - also - even with both of these additions - it would be likely for such a signal as a junction home signal to be an inner home protected by an outer home. Anything to the right of the centre line was "wrong side" and had to be individually justified. Post 1889 (if not earlier) the influence of the Board of Trade meant that signals were placed to the left of the line to which they applied or above the centre line. However, even then, I'd be extremely surprised to see a bracket signal in the V between two converging lines. Unless you can come up with an example somewhere in the UK - that is - outside the very early period when some truly weird things were done (by later standards) as regards signal sighting. I'm going to strongly disagree with you on item 1.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |