johnpenn74 wrote: ↑
Wed Jan 02, 2019 3:41 pm
The signals are there to prevent three things, front end collisions and rear end collisions and derailments from too much speed in a route change.
In their common usage on ride-on railroads (in my opinion) signals are almost 100% "Route" and/or "conflict" (as you point out above) indications - not "speed" indications.
The average 7.x" engineer can easily handle that Yellow boils down to "the block ahead is clear but the block ahead of that is occupied" but it is not 'normal' in his experience that it's telling him to slow down (remember, 7.x" stopping distances are much shorter than prototype).
Even at a turnout, an engineer is way more likely to use his judgement on the correct speed for a turnout (right or wrong) rather than thinking "yellow means I need to use X speed" so you might as well present green or yellow based on track ahead rather than "speed" - but, I see no harm in using yellow when it would have otherwise been green - just don't get upset when 90% of engineers don't treat it as a "slow down".
Most times in 7.x" practice the signals are not located at separation distances dictated by scale stopping distances or scale train lengths (EPRR may be different, I don't know) but more based on where a track is going (double-head at a facing point move) or single-head to de-conflict (guarding a diamond, trailing point move/merge, etc.) - again, nothing really to do with speed in 7.x" practice.
In my experience, most railroads are not fully
signaled - in other words, there are areas of "dark territory" (single uni-directional trackage, sidings, etc.) where the engineer is still responsible for maintaining separation distances even at a track with signals. This also holds when a train is pulling in behind another train at a passing siding (he needs to see and slow down to avoid rear-ending the train in front) unless you are going to place extra signals to control movement into the siding itself.
Which brings up another point: In my opinion (during a meet where there are lots of visitors) all
signals should be absolute. I don't think we can rely on everyone to stop and proceed at 'dead slow' into a siding given a red at the entrance and yet know to "Stop and Stay" at a head-end signal - even with the use of a number plate being there or not. This means that (in the siding example above) we have no way to tell him to pull into the siding slowly because of the train ahead (if red means stop and yellow and green mean go). We have to rely on his observation of following distance.
Now, if a railroad absolutely wants/needs to have "permissive signals" and they want to use them for visitors I would think that a 50% flashing red could be used (like a flashing traffic signal at road crossings) because the average person has some familiarity with that or by placing a sign on each permissive signal that says something like "On red you may stop and then proceed at low speed to the next signal".
johnpenn74 wrote: ↑
Wed Jan 02, 2019 3:41 pm
So I have to ask, if you not going to stop at a red signal for the occupied block in front of you, or start slowing because you have a yellow approach, then what's the point? Basically operators are just blowing off the very devices that were put into service to help protect the system in the first place. So signals are just there to be pretty and ignored?
I just don't get it. So many people at the clubs have a mentality of "This is a hobby so what can I get away with". Signals are designed and placed to improve safety, too bad if that's inconvenient. Maybe after we plow enough cabooses people will get to the point to ether slow or obey signal protection on a blind curve.
I guess it boils down to the philosophy of the railroad. Just as some railroads have designated themselves as "Steam Only" a given railroad can state that their signals closely follow prototypical practice and must be followed as such. This is easy to do on a private railroad or one where only members run. If the railroad wants to be open to general visitors (meets, etc.) and even if you offer extensive classes compressed for time (remember, what seems simple to you may be very complex to visitors) you need to be prepared for accidents (they forget or miss-interpreted something), and/or ask them to leave if they are not following the rules. Not "friendly" or practical in my opinion.
This is one reason I advocate solid-state signals for large tracks - it allows you to have one operating mode for "the gang" who want's to adhere to prototypical practice as closely as possible and another mode to be used during a meet, etc. (where "Green or yellow means go, anything else means stop") - no changing of wires, diodes, etc. just a software command ... Your mileage may vary