perhaps it’s not obvious enough that it needs to be pointed out, but did you notice the tunnel depicted in the diagram, on the other side of which was Manilla tower ? thanks for your clarifications
In the interest of being pedantic…
A wye is a meeting of three tracks, where approach on any track can be routed to any other track. A “wye” is not a switch or turnout.
Some wyes have one or more equilateral turnouts, but this is not a requirement of a wye’s track design. An equilateral turnout is a turnout without a “straight” or tangent path—both routes “diverge” and by the same angle.
If a switch has two diverging routes, it is not necessary that both routes take off at equal angles, so maybe it would be better to call it a double diverging switch.
Well, maybe so, or maybe not. There is a very long well established use of the term “wye turnout” or simply a “wye” to describe an equalateral turnout in the model railroading hobby. EVERY track manufacturer, current and past uses the term. NO track manufacturer uses the term “equalateral turnout”.
Countless authors, manufacturers, and modelers understand and use the term to describe either, the single equalateral turnout, or the three track junction.
Merriam-Webster #1 definition :a Y shaped part or object
I think the single piece of track meets that definition rather perfectly.
Our friends across the pond at Oxford:
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NORTH AMERICAN
They call it a wye because it is shaped like a Y.
Why? Why not? [swg]
Rich
Maybe it’s regional, but the only time I ever heard of “Wye” was when referring to an actual wye arrangements of tracks that allowed turning of equipment (or sometimes referring to tracks that once formed a wye, but now part of that wye is missing, but the rest of the remaining tracks are still called a wye - even though you can’t wye anything on it).
And yes, we do use wye as a verb. “go and wye that power”.
An equliateral switch was always called that, and never a wye switch (as far as I can remember).
It was pretty obvious to me from the beginning that he’s discussing the ‘wye switch’ that is at the apex of a conventional ‘wye’ – the one that is an equilateral switch between the two legs. This is what Wikipedia suggests be called a ‘turning wye’ to distinguish it for would-be pedants.
And he’s asking what the ‘normal’ position of a switch with no natural normal or reverse is. In CTC that problem could be addressed via current-of-traffic concerns. Here it would have to involve a railroad rules convention, something like “looking at the apex from the main, ‘normal’ is lined for the right approach curve, and ‘reverse’ for the left.”
For a spring switch the issue is moot, because the locomotive or train can approach from either direction, and the switch would then have to be lined against spring pressure to exit the opposite way but then be simply released and locked.
I wonder what the terminology mavens would use to discuss the switches at the apices of a ‘star’ (which is like a folded wye with less required curvature for a tight fit).
From the Wikipedia introduction to wyes and their terminology (which happened to be easy to locate and paste):
[quote]
The “reversing star” (red) compared to the ordinary wye (blue)
If there’s a target, then which ever side would make the target green or white? (or whatever color scheme is in use. Even yellow vs. purple? Don’t laugh - it’s a thing).
I’m actually thinking that if you have the ‘red’ and ‘green’ targets at an angle to each other, instead of at right angles, they could clearly and unambiguously indicate ‘go’ for a train moving on the leg the switch is lined for, and ‘no go’ for one on the opposite leg, which seems to me to be precisely what is wanted.
How you ‘remote’ this to a model railroader’s console that only shows green and red for how the points are positioned … or on a CTC board with similar control display ‘modality’ … is a more difficult issue.
OK, I’ll bite… what are yellow vs. purple used for?
Normal vs. diverging off a siding. I believe yellow was normal? Or was it for the derail right next to it? It’s been awhile. One of the 2. We don’t target shoot - always look at your points.
I always watch when people type in the spelling of my last name. I tell them that it begins with a "Y’, and they type “W”.
As a sort of aside: this is precisely like an issue I came upon in ITU group R10 about repeaters for emergency nuclear power-plant management. The normal (no pun intended) convention for valves is ‘green open, red closed’ without any indication for whether those valves were supposed to be NC or NO. Semantically this has been a source of confusion and delay under stressful conditions. We developed the convention that the repeater, using bipolar R/G LEDs, should display green for ‘normal operating position’ (with the understanding that the existing control display would remain as built, and could be quickly consulted for physical state). If there were a proportional signal for valve drive position, it would show an ‘offset’ of modulated red and modulated green together, the result being a graduated orange that also served to indicate how far toward ‘expected’ condition the valve had reached… note that this inherently separated ‘just cracked open and leaking’ from ‘not quite closed and dribbling’, something of key importance in the TMI accident.
What I’d use for the wye display would not be ‘green’ or ‘red’ lights but two white lights either side of the apex switch on the panel track-diagram line. The appropriate light would show what side of the wye was lined for the stub.
Here is a product intended to assist with the concerns of switchmen, they say:
https://www.aldonco.com/product-category/signs-and-lights/turnout/
Why? [:-^]
If you have to put up a sign telling people how to read a switch, that person really shouldn’t be touching switches. Or be out there by themselves.
Remember that we’re half a century on from the era that the Army had to produce comic-book manuals for the M1A1 tank… and not a witty update of a Tigerfibel, either!
This is, alas, the sort of “upgraded” signage marketed and sold to MBA-trained purchasing agents who have likely never switched anything complex… but are acutely aware of their legal department’s natterings. (Of course that’s my non-railroader’s opinion, so take it with the usual lost shaker of grains of salt…)
In Aldonco’s partial defense, though, I am in favor of things that would foster unambiguous ‘safety’ especially in poor weather or for tired or exasperated men. If one of these patent Bold New Theory products actually does that, I’d be in favor of at least testing them…
In real life on the prototype yes, equalaterial switch, but in the hobby, on the package you buy it in “wye”, from every model train track manufacturer in the last 70 plus years.
Sheldon
In the Canadian context, red and green was used when the turnout is on the main line. Yellow and green are used on yard tracks. Purple is for a switch point derail.