Well explained Mark, thank you.

Thank you for the nice video. Signals and traffic control are my "railfan specialty" so I know a lot about it. (I would think a Signal Maintainer would be an enjoyable job for me, except maybe for the heights...) Signaling has a lot of details, so I want to help out with some definitions that are often confused (even by RR personnel) : ASPECT - What the signal looks like. e.g. Colors, multiple colors, movable arms, colors and shapes on those arms, colored disks, signs, etc. INDICATION - The response of the train crew in compliance of the aspect-what the signal *indicates* the train crew should do in reaction to the signal, as specified in the rules. RULE - The specific item in the rule book that equates one or more signal aspects with an indication. Rules have NAMES and NUMBERS in addition to the written indication. RULE NAME - What the signal rule or aspect(s) is properly called. "Approach Diverging" for example. RULE NUMBER - The number of the rule in the rulebook's or Special Instructions's numbering scheme. "9.2.5" for example. 👍

I’m a retired locomotive engineer and I think you did an outstanding job on explaining signals and signal aspect. Enjoyed it. 👍👍👍❤️

@MarkClayMcGowan

3 жыл бұрын

Thank you! That's high praise coming from one who relies on our stuff working right to operate safely. Thanks for checking it out!

@emmanuelescarment2034

2 жыл бұрын

i want to become locomotive engineer how should i start?

@kevinpurcell2093

Жыл бұрын

I am a railroad fan & his explanation was easy to understand. Thank you for the video.

I appreciate the videos from you

@MarkClayMcGowan

2 жыл бұрын

I appreciate you checking out the channel!

Excellent video on signals, I am a working member of a active RR. museum, and we are required to know signals and other very important rules before we are allowed to move any real railroad cars or locomotives on our railroad. We are required to pass this test every two years.

Thank You for explaining what those signals mean! I have always wondered what those signals meant & my curiousity has gotten the best of me. I somewhat knew that red, yellow & green had the same the 'meaning', but I really never understood (in depth) of what they really meant. I've been dying to know for such a long time. Thank You again!

@MarkClayMcGowan

3 жыл бұрын

My pleasure! Glad it explained a few things!

Wow! You've really taught me a lot about the color system! I've always wondered about it. And what makes this even 'greater'...........is that I get to inform my husband about this! Ha ha! More importantly, I now understand more about why trains take so long at a crossing. There really IS a reason to it............they aren't just 'taking their 15 minute break'. LOL! This video was very informative, thank you for this information. I realize, and appreciate, that this 15 minute video that you made for us probably took you about 3-6 hours to edit and get out there to us. Thanks, Mark! You are awesome!

@MarkClayMcGowan

3 жыл бұрын

Thank you for the kind words! More than editing, it took forever to shoot because I had to wait for certain signals! I am happy I was able to clarify some things for you! Thanks for checking out the channel!

Excellent informative video, thank you.

Excellent video Mark. Great job on explaining the different aspects. You should do a part 2 on how 3 headed signals work.

@MarkClayMcGowan

5 жыл бұрын

I'm putting one together of various aspects at ends of sidings

I never knew what all the signal colours meant. Thank you for helping to clear some of it up. :)

@jovetj

Жыл бұрын

Just remember: Each American railroad has different rules for signals. The meanings of the combinations of lights will be different in different places, even on the same railroad.

@thomaskirby6706

Жыл бұрын

@@jovetj that sounds like an accident waiting to happen.

@jovetj

Жыл бұрын

@@thomaskirby6706 You're not the first person to say that. But it isn't that big of a deal. Remember that all train crews have to be _qualified_ on the tracks on which they operate. You cannot just get placed on a locomotive and run a line you've never seen before. The crews have to know where each curve, signal, speed restriction, grade crossing, etcetera are. They must memorize the signal rules for their territory in their entirety. So, there are incidents where multiple signal systems are in effect for a train crew in different spots and they've gotten confused, but those are not that common. This is also more an issue on eastern railroads where multiple predecessor railroads have never been brought into unity. The cost of changing the signals in the field and retraining crews is a real obstacle. This situation doesn't exist on BNSF and UP because their systems are more-or-less unified on their territory (because it was cheaper to accomplish at the time of merger).

@thomaskirby6706

Жыл бұрын

@@jovetj Thank you for the excellent response. :)

@jovetj

Жыл бұрын

@@thomaskirby6706 Sure, I'm happy to help! As a railfan, signaling is "my thing."

Really enjoy your informative videos on railroading.

Things have gotten more complex yet given more options. My uncle used to operate trains four Southern Pacific and he told me of a problem that occurred years ago. There was a terrible train accident out in Nevada. Originally my Uncle was supposed to be on that train. My Grandmother told me she called the railroad saying her son was on duty on a train. He wasn't; a change had been made. In those days there was no dead man's switch on the engine. The lights were green (no problem for two signal or more; clear), yellow, (next signal is read) and red (A train or obstruction between this signal and the next) . To open the throttle a rod was pulled out. To release the throttle the rod was pushed in. The engineer leaned on the throttle rod. He died of a heart attack but was still leaning over the throttle rod so the train continued to travel. It went through more than one yellow without slowing down. Finally it went through, if I remember right, two red signals at full speed before suffering a disastrous collision that took a number of lives. The other people in the engine survived and knew nothing of railroad signals. They did not know that the engineer was already dead. My Uncle did know these things about trains. Had he been there the disaster would never have happened.

@billmorris2613

3 жыл бұрын

I’m a retired road engineer off the Union Pacific. The other crew members in the engine cab would have known the meaning of the signals and the reaction required of the engineer. Depending on how long ago this accident was there could have been two other crew members, a fireman and the head brakeman. If it was in the last 25 or 30 years ago the conductor would have been in the engine with the engineer. And possibly a fireman and a brakeman could have been in the cab too. So if none of the other crew took action to stop the train they were either asleep or you have your facts wrong.

Hey handsome I enjoyed watching your video thank you for explaining how signals work

@MarkClayMcGowan

2 жыл бұрын

Why, thank you for BOTH compliments! It is greatly appreciated!

@taylorpinkney7253

2 жыл бұрын

@@MarkClayMcGowan anytime sweetheart ❤️😘

OMG Finally someone explains so I understand!!

@MarkClayMcGowan

4 жыл бұрын

Glad to be of help! I hope you find the time to check out ALL my videos but particularly the "how things work" videos! Thanks for checking out my channel!

@rxramblingrose4857

3 жыл бұрын

Same I love this mans wisdom understanding something and learning is SAFETY and knowledge of railroad language Much respect ✊ I hope you are doing well I didn’t know there was a number 2 The first one I go back and REFRESH my memory Very grateful for your time, effort, and commitment to teaching and sharing Thank you 🙏

Hello mark

Love your channel Mark

I have an examination for a job like this, thanks 🙏 for the information, I appreciate it! 😃

Thank you so much for doing your series on signals! We own a hobby shop with model railroad components and get so many questions about how and when signals do different things on the railway, so it's great having an easy to follow reference video. Plus I've learned a lot myself through your vides especially the one where you show the inside of a signal shed. Keep up the great tutorials!

@MarkClayMcGowan

2 жыл бұрын

Thank you! I'm glad you enjoyed them!

Great explanation, Thanks !!!!!

Movement must be made at a speed that allows stopping with half the range of vision short of....Mark! Thanks for the comments on being a locomotive engineer, you are 100% correct! Lives depend on everyone following the rules. That said, it was the best job I had.

@MarkClayMcGowan

4 жыл бұрын

Yeah, I don't write a script when I do these. Maybe I should! I couldn't remember the wording. I figured someone would correct me. I'm surprised it took so long! The RR was a great job. It annoys me when I hear people whine about it. Thanks for checking it out!

@LouT1501

4 жыл бұрын

@@MarkClayMcGowan something I have noticed since the change to PTC on the UP main here (Brooklyn Sub in Oregon): prior to PTC, the signals used to light up as the train entered each block, 'approach lit.' The controlled signals near my house (I live next to the mainline) have been lighting up when the train is a ways away, three or four signal blocks away, sometimes. Some times not. I don't understand the inconsistency. Any thoughts (thank you)? I wrote that comment with the Restricted Speed thing early on in the video, no criticism intended. Hope you're having a great retirement!

@MarkClayMcGowan

4 жыл бұрын

@@LouT1501 many locations are programmed to light when a route is cleared, including intermediates in the block and some are still approach lit. We were told we could reprogram them to do whatever we wanted but it wasn't worth the time.

Enjoying the video's. For a time, we had a lunar or white signal indication on one of the signal masts here in southern Illinois.

@MarkClayMcGowan

3 жыл бұрын

I was always a fan of the lunar. Beautiful signal.

@alanbaum3228

3 жыл бұрын

In NYC we used to have quite a few lunar white signals. They were used as train speed regulators. They're disappearing as more and more the system is transitioning to Communication Based Train Control.

@jovetj

Жыл бұрын

Lunar White and Flashing Red both generally mean "Restricted speed" on many US railroads. Purple used to be used on dwarf signals back in the day instead of Red to try and avoid confusion with background lights at night... but that faded out of use as it didn't really seem to be that big of a deal. Blue lights used to be common on doll arms, but they're rare to find now. Clear white (not lunar white) signal lights are still around, mainly on CPL signals; 4 of the marker lamps are clear white, not lunar white, the other two are yellow.

WHAT DETERMINS the number of engines on a train, and where DPU's are placed?

@billmorris2613

3 жыл бұрын

The number of engines placed on a train is determined by several factors, The horsepower (tractive effort) of each engine, the gross weight of the train, maximum track speed, rather the train will operate over flat, hilly, or mountainous territory. I never used DPU but probably the ones already mentioned above plus the length of the train and the make up of the train (how the loads and empties are distributed in the train.)

Another good explanation of how railroad things work. Hope the modern day people can get a grip on it.

@MarkClayMcGowan

3 жыл бұрын

Thanks for checking it out! I'm glad you enjoyed it.

@billmorris2613

3 жыл бұрын

It’s like many other jobs with a lot of responsibility. With proper training and annual testing it becomes second nature. But if we forget, we are required to have the rule books, timetable, and operating manuals with us. The rule books are a loose left type book and when changes are made we remove that page and insert the page with the new change/s. There are methods of updating the other publications we carry with us too. The books we have to carry with us is a very small percentage of all the rules and regulations for the railroad industry. The FRA is to the railroads, as the FAA is to the airlines. Each department in both industries has their own set of rules and regulations. Both sets of rules from the FRA and the FAA weigh about the same. If you put them all on a train they would each need their own box car. If we used an airliner they would each need a few 747s. Well, that may be slightly exaggerated.

Chivey Dealership?

Thank you. I looked all over looking for this information.

Another great video. Great job Mark

in my country there is a signal - three yellow, which means movement on the station's track occupied by a train, the speed is 25 km / h.

So if your vehicle somehow becomes stuck on the train tracks would it be a good idea to short the rails with jumper cables or something? What about putting a button at rail crossings motorists could push it they get stuck or break down??

@MarkClayMcGowan

Жыл бұрын

You could do the jumper thing, but it may or may not make good enough contact to create a stable short. If you can see a train, just get away from the car and walk in the direction of the train; that way, if the train hits the car, it knocks it the other way. There is a phone number on all crossing cabins if you're near one. Call and give them the information on the cabin. If they put an emergency button on cabins, people would just push it all the time. Always pay close attention to the signage when approaching crossings and never cross the white lines once the lights start flashing. Thanks for asking and for checking out the channel!

Nice job on explaining the signal lights.

It's my understanding that the major RRs (UP/SP, CSX, NS, KCS) have different signalling. Is that true?

@MarkClayMcGowan

4 ай бұрын

The simple answer is yes, but it's a lot more complicated than that. Maybe I'll do a video about it after doing some more research. Thanks for checking it out!

Great info .......I work at the port of Long Beach ca, and almost all the signals are flashing Red

@apachinook998

3 жыл бұрын

a normally lit traffic light is red. Yellow or green is an "open signal" that gives the right to depart or arrive by train. Imagine if all signals were always open

@jovetj

Жыл бұрын

Flashing Red on a western US railroad usually means proceed at Restricted speed.

👍👍👍❤️

What is a flashing green?

@MarkClayMcGowan

2 жыл бұрын

I only know of it in a yellow over flashing green aspect with an indication of "approach sixty". The next signal would be red over green at the control point for a sixty mph turnout.

@jovetj

Жыл бұрын

It's whatever the rulebook says it is. Do you have a particular railroad in mind?

@RiverWalk_Railfan

Жыл бұрын

@@jovetj well I get UP, BNSF & Amtrak but the tracks are owned by UP

@jovetj

Жыл бұрын

@@RiverWalk_Railfan It's who owns the track that matters. UP only has two Flashing Green aspects. Y/fG is _Approach Clear 60_ to slow down to 60 MPH by the next signal. R/fG is _Diverging Clear Limited_ which is another display "route" for Limited Clear, for a turnout 40 MPH or less.

Is there a standard distance between signals ?. Or minimum distance ?.

@MarkClayMcGowan

2 жыл бұрын

No, there is not. It depends on a few different things such as grades, curves, etc. On straight or good visibility track they are usually about two miles apart. Thanks for checking it out!

Great video

I've also heard the term "home" signal and "distant" signal, perhaps terms used more historically on railroads. Are control and automatic signals any different?

@sercancelenk7131

3 жыл бұрын

"Home" and "Distant" definitely comes from British rail, they used to have only two signals for a station, one at the station and other one leading to it. Now we have more signals betwen stations to allow more trains to be operated in the section. Control signals are controlled through signaller panel (a.k.a dispatcher in US of A) but Automatic signals are controlled only through track occupation, no need for human interference. Automatic signals are suitable for straight sections of tracks without any switches.

@MarkClayMcGowan

3 жыл бұрын

On SP lines we used "H" and "D" designations for signal circuitry until the new system was upgraded 2010-2016.

@billmorris2613

3 жыл бұрын

We used distant signals for approaching a draw bridge or crossing another railroad in dark ( non signaled ) territory.

@MarkClayMcGowan

3 жыл бұрын

@@billmorris2613 they still use them on branch interlockings here too. We have no navigable waterways in my corner of the railroad so drawbridges are just something we hear about!

@billmorris2613

3 жыл бұрын

Mark Clay McGowan Between New Orleans and Alexandria we have two draw bridges. One crosses the Intercostal Water Way a few miles north on Addis, LA. A few months after I hired out in 1973 we had a train hit the concrete counter balance with the bridge up and the signals were clear. The signal maintainer that was first on the scene after the accident transferred to engine service and I had him as a trainee. He told me the four spring loaded plungers stayed down because the tops had mushroomed from years of use. Back then the bridge tenders did not have radios to talk to the trains. The bridge tender was having a problem getting the bridge to come down. He lined his control board for clear signals hoping that would get the bridge to lower. He did not know the plungers were stuck in the down position so the signals went to clear. If any one of them would have come up the signals would not have cleared. The engineer and head brakeman were both killed. The other bridge is over the Atchafalaya River at Melville, LA. We also have two going west toward Houston. The one North of Addis and one over the Atchafalaya River at Krotz Springs, LA.

Presentation would be so much more effective with visual examples. But I enjoyed nonetheless!

@billmorris2613

3 жыл бұрын

There was visuals of each signal before he explained their meaning.

So, let 's say my car stalls on the tracks at a crossing, and I call the 800 number on the crossing bungalow, is what will happen that the dispatcher will flip a switch to put the signals in the vicinity of the crossing red?

@MarkClayMcGowan

2 жыл бұрын

If your car stalls on a crossing, it's because you either stopped on the tracks or rolled onto them without knowing if you could get across, and both are illegal. For informational purposes though, yes, if you call that number, any trains in the area will be notified and entering control signals put to stop. If that does happen, leave your car, move away from it and do not return to it for any reason. If a train approaches, walk TOWARD the train. If it hits the car, it will knock it away from you. Thanks for checking it out!

@876statestreet

2 жыл бұрын

@@MarkClayMcGowan Thanks! And yeah, remembering the Fox River Grove Story all too well, I would definitely never venture across unless I were sure I could completely clear it.

How far apart are signals/ control points?

@MarkClayMcGowan

2 жыл бұрын

Generally about two miles but there are places where they are closer depending on grades and sight distances. Thanks for checking it out!

@jovetj

Жыл бұрын

Most signal blocks are 1-4 miles long. 1-2 miles is pretty common. The braking distance of the heaviest, fastest possible train on the line is a big factor on that. Control Points can be immediately adjacent or 30 miles apart. A control point can be a complex interlocking with dozens of tracks or a simple holdout signal (which would otherwise be Intermediate, but isn't) just outside of town. The needs of the customary traffic on the line determines where the control points (and other features such as passing sidings) are. One stretch of double track might have crossovers every 5 miles, and another might have them every 20 miles. It just depends. If you look at something like Tower 55 on Virtual Railfan, you'll see lots of back-to-back controlled signals. Those are multiple control points that are adjacent.

What is a LUNAR signal?

@MarkClayMcGowan

3 жыл бұрын

A lunar signal (so named as it is about the color of the moon) is used to move a train into an occupied, signaled track such as a siding with another train stopped in it. The aspect would be red over lunar where moving into an unoccupied track would be red over yellow (or whatever the circuitry called for). Around here, the lunar was replaced by flashing red. Thanks for checking it out!

@jovetj

Жыл бұрын

Lunar _white!_

What happens if an engineer happens to look away while passing thru a signal and misses it?

@shauntrailskinner9645

3 жыл бұрын

@Marty Martian I-I-I reckon that poor slob would be coinfine to being a janitor at that thar UP HEADQUARTERS, shining up dem floes pardna. 🤠 Jethro

@MarkClayMcGowan

2 жыл бұрын

They're visible for quite a long way, especially on straight track. In curved territory the speeds are slower and still give ample time to see the signal. There have been instances though, where the crew have fallen asleep or have been distracted such as the Chatsworth Metrolink v UP freight head on in 2008 when the engineer was texting.

@martymartian9820

2 жыл бұрын

@@MarkClayMcGowan Wonder why they don’t have a trigger to notify a crew when they are in the vicinity of lights, instead of counting on them not to text or fall asleep?

Good morning from SE Louisiana 19 Mar 21.

@haywoodyoudome

3 жыл бұрын

What's with putting the date on comments? Nobody gives a shit.

@billmorris2613

3 жыл бұрын

haywoodyoudome Your attitude in the question does not deserve an answer, but I will give one for the other people that may read these comments. And I could care less what you think about it!!! I have been doing it for over a year and you are the first one to even mention it. The date is for my use, and I only put a date on my greeting comment. Which is on every video that I have watch since I started adding the date along with a like or dislike.

@jovetj

Жыл бұрын

@@haywoodyoudome I give a shit. It's my birthday!

Hi Mark. Enjoying all your videos. I was hoping you could answer a question regarding a piece of SP signal equipment I saw back in the 1980's. I was on the SP Palmdale cutoff and saw a large display next to the mainline that had a 3 numeral digital board and a red revolving light on the top. I just got a quick look at it and would assume this is the old hotbox detector???? So would the board display the axle number for the employee in the caboose if there was a defect?? I've done a bit of research on the internet but can't seem to find anything about this item...Thanks in advance..Jeff

@MarkClayMcGowan

4 жыл бұрын

That's exactly what it was. There were also two white lights on top of the numeral board to indicate which side of the train the hot box was on. Thanks for checking out my channel!

@dunsmuir238

4 жыл бұрын

Fast response....Thanks. When did they stop using those? I always wanted to see one in operation. Very unique...I can't even find a photo of one on the internet. Was there a specific name for them???

@MarkClayMcGowan

4 жыл бұрын

@@dunsmuir238 tracksidetreasure.blogspot.com/2009/10/hot-box-detectors.html?m=1 try this

@MarkClayMcGowan

4 жыл бұрын

@@dunsmuir238 they stopped using the numerical display board type in the mid 80s when they were getting rid of the caboose.

@dunsmuir238

4 жыл бұрын

Thanks so much for both responses. Much appreciated. Looking forward to more of your videos!!!

Hi Mark. How does an engineer recognise whether a signal is controlled or automatic?

@MarkClayMcGowan

2 жыл бұрын

It depends on the railroad, but in my corner of the world, automatic signals, whether CTC intermediates or signals in automatic block, have number plates, controlled signals do not. Thanks for checking it out!

@jovetj

Жыл бұрын

The rulebook! That's how. 🙂

@Messicrafter

Жыл бұрын

Conductor here. As Mark says, most North American Railroads will mark intermediates/Automatic Block System (ABS) signals with a number plate that has the milepost on it, while Control Points (CP) don't have number plates and are usually marked on the "Timetable" map and on the signal house nearby.

Nice graphic

How long are the blocks generally and do these vary in mountainous country or commuter routes? Anthony

@MarkClayMcGowan

3 жыл бұрын

blocks around here are generally about two miles long but there are certainly exceptions. As far as commuter lines go, I really do not know. Thanks for checking it out!

@jovetj

Жыл бұрын

They typically vary between 1 to 4 miles. They are usually spaced according to the stopping distance of the fastest, heaviest train. If any train train cannot stop from an _Approach_ to a _Stop,_ the more aspects have to be used, which is where things like _Advance Approach_ come in to play.

Hi Mark, I was wondering how often a train is given a signal. Thanks

@MarkClayMcGowan

4 жыл бұрын

It depends on track speed and braking distance. On the Tehachapi it's about every mile. Higher speed track about every two miles. Thanks for the question and for checking it out!

You touched on a subject talking about the red signal that if something shorted out the rails it would go red. I saw a situation where a car tried to cross the track, not at a crossing. and the front would have been hit by an approaching train. I know that the old block signals on the Santa Fe operated on the principle that if you introduced a "Short" across the two rails, the closest signal in either direction would go red and the next would go yellow. The short could be introduced by throwing a set of snow tire chains across the two rails or using a set of battery jumper cables. Do all U.P signals work the same way even on the roads absorbed in the last set of mergers? Would the same principle work in the area of a grade crossing where the track is isolated from the rest of the block for the operation of the crossing signals?

@MarkClayMcGowan

3 жыл бұрын

Yes. In signaled territory placing a shunt across the rails with put all entering signals to stop (hopefully a train hasn't already passed the signal!) and give the dispatcher an indication on their board. In non signaled territory if you have a flare (at night), place one between the rails on each side of the obstruction. In daylight, if you see a train approaching, walk toward it waving anything you have below your waist (called a "washout") from side to side. A shunt will activate a crossing as well. If you want to keep the crossing activated the has to be within 50 feet of the edge of the road. Beyond that, the controller will see it is not moving and recover the system. I have a piece on how crossings work in my "How the Signal System Works" playlist. Thanks for checking it out!

@jovetj

Жыл бұрын

Just remember that there isn't a lot of voltage across the rails... so some things just casually laid across them will not be conductive enough. Rusty rails and rusty train wheels are a big problem in this regard (rust doesn't conduct). A tarnished or rusty chain might not do much, but jumper cables are good.

When the signals went out at night in a remote location out in the middle of the desert where it was pitch darkness, would you guys head out there at night or would you guys wait to do it in the day? I’m assuming for your safety you guys would wait for the day time.

@MarkClayMcGowan

3 жыл бұрын

We were called immediately on light outs. Weather and darkness weren't a consideration when the system was having problems with the occasional exception of problems in sidings that weren't going to be used.

@stripervince1

3 жыл бұрын

Dark is as good as a red

How do the intermediate signals know the state of the next signals ahead of them?

@MarkClayMcGowan

3 жыл бұрын

Information is always being sent from signal to signal through coded pulses on the rail or, in older systems, over open wires or in cable on the poleline next to the tracks. Each location has a transmitter and receiver (or battery and relays in older systems) that determines the aspect. Intermediates are automatic and will display whatever aspect the receiver tells them to display in both directions until a route is cleared in one direction at which time all opposing signals "tumble down" to red. I hope that answers your questions and thanks for checking it out!

@russelljenkins8866

3 жыл бұрын

@@MarkClayMcGowan Yes it does, Thanks!

I’ve only operated on east coast railroads under NORAC and GCOR rules. I’ve heard there is a fundamental difference between signaling on eastern vs western railroads: that eastern signals denote speed information e.g. slow, restricting, advanced approach, medium approach, approach , clear. And that western systems show condition of signals ahead. Is there this difference?

@MarkClayMcGowan

3 жыл бұрын

It's essentially the same. The engineers call out the signal by name as you indicated and they are listed in the Special System Instructions for UP. All indications give information about the track or signals ahead. I do know that different roads have different names for indications. Thanks for checking it out!

@jovetj

Жыл бұрын

You're talking about the difference between _Speed Signaling_ and _Route Signaling._ For the most part, the differences are subtle. In the U.S., the only real difference is how diverging aspects (for changing tracks) are handled. In a Speed Signaling system, the signal indication itself prescribes the maximum safe speed for the switch(es). These speeds are generally standardized and are usually around 15 MPH for Slow speed, 30 MPH for Medium speed, and 45 MPH for Limited speed. When a signal shows _Limited Clear,_ the crew automatically knows it should be able to go 45 MPH (or whatever the rule is) through it. The distant signal (the one encountered before the _Limited Clear_ ) will usually show _Approach Limited_ to indicate the maximum speed of Limited speed at that next signal. With a Route Signaling system, the signal aspects generally describe the route to be taken, and not the speed. The speed for the given turnout is listed in the timetable, and must be known in advance. Speed signaling is more flexible, but it also has many overlaps. Let's say that one signal protects a track that splits into three tracks. The first switch might be 35 MPH and the second switch just after it is 15 MPH. The signal can show _Diverging Clear_ as Red over Green over Red for the 35 MPH track and as Red over Red over Green for the 15 MPH track. The train crew has to know this distinction; but the distant signal (encountered before the diverging signal) can also hint at the speed required at the next signal. That distant signal would likely show Yellow over Yellow _Approach Diverging_ for the 35 MPH switch, and Yellow over Red _Approach_ for the 15 MPH switch. If we alter the example and make both turnouts 35 MPH... then the diverging signal might still work the same way! Or, more likely, it would just be a 2-head signal, and show Red over Green for either route. If the speed limits are the same, then actually knowing the route to be taken doesn't matter as much. Generally speaking (for class 1s): UP - Route signaling BNSF - Route signaling CSX - Speed signaling (multiple schemas, depending on the location's predecessor's practices) NS - Mix of both Speed and Route signaling (depending on location's predecessor's practices) KCS - Route signaling CN (US lines) - Route signaling CP (US lines) - Route signaling Amtrak - Speed signaling NS's "official" signal schema is Route signaling, but former Conrail territory can be Speed signaling. CP and CN are all Speed signaling in Canada in the standardized rules there, but the "DIV" aspects and indications are essentially Route signaling exceptions. Many people may see speeds and rules like BNSF's _Approach Medium_ and think "Speed signaling!" but that is incorrect. This may be controversial to a few people, but safe train handling rules do not, by themselves, define a Speed signaling system. UP's _Diverging Clear Limited_ is NOT a Speed signaling aspect, as such do not use arbitrary speeds like that rule does.

I see the different signals and wonder what they really mean. Thanks for the info. What about the red over green? Or vice versa?

@MarkClayMcGowan

3 жыл бұрын

I go over that in part 2.

@raylrodr

Жыл бұрын

Diverging Clear. Proceed on diverging route at prescribed speed through turnout.

Can someone tell me how long is a block which a signal protects.

@billmorris2613

3 жыл бұрын

It could be any where from a few hundred feet to several miles. On a territory with Automatic Block Signals (ABS) it was usually 2 to 4 miles on the territory I worked on. Maximum track speed grade (up or down hills or mountains), what the signal protects, like a draw bridge, junction of tracks, crossing another track, are a few of the major factors that determines the distance between each signal.

@johnmeadows5645

3 жыл бұрын

@@billmorris2613 thanks Bill

7:18 At the risk of saboteurs laying some metal from rail to rail, if a car or truck got stuck on the rails at a crossing, could shorting out the rails signal a dispatcher or engineer to slow down or stop before the crash? Penalty for false alarms?

@MarkClayMcGowan

3 жыл бұрын

If the vehicle were across both rails, yes, it would cause the signals entering the block to turn red. If a train were already past the signal when the vehicle got on the tracks there would be no way to warn the crew and you'd have to just hope they saw you in time! If you ever find yourself in that situation, get your jumper cables out and connect them to both rails. If you see a train coming, walk TOWARD the train and away from the tracks. We get "indications" all the time and they are caused by many things. If it's a maintenance issue you will definitely be explaining it to your boss the next morning! Thanks for checking it out.

@ProperLogicalDebate

3 жыл бұрын

@@MarkClayMcGowan I don't know but (How many times have you heard that? LoL) therefore connecting a battery cable would be the next highest priority below lifesaving so an engineer would see the signal. Above phoning 9-11. Wouldn't the Dispatcher also see it and radio the engineer to stop even if the last control signal was past?

@MarkClayMcGowan

3 жыл бұрын

@@ProperLogicalDebate once a train has passed a control point the track to the next control point just shows occupied on a dispatcher's board. Sometimes there are split blocks but that's rare these days. Intermediate signals are automatic and will go to red in such an instance but the dispatcher can't tell what Intermediates are doing. If there are no trains between control points the dispatcher will see the indication and either stop trains at the CP or flag them into the block at restricted speed (a speed not exceeding half the distance it would take to stop short of another train, misaligned switch or anything blocking the track). At that time signal and track are notified of the problem and dispatched to the area and are notified if a call comes in about a vehicle on the tracks. I hope that helps!

@jovetj

Жыл бұрын

It's really safer to just call the railroad as quickly as possible, and know your location to tell them where they are so they can stop the trains. Get everyone out and away from the vehicle.

Editing and writing a script goes a long way. Good information but definitely needed better planning

@MarkClayMcGowan

3 жыл бұрын

I'm not a professional and this isn't my job. It's just a hobby in which I attempt to clarify things I know people are curious about. This was one of my early pieces and while I have gotten better at it and sometimes write down guide posts to keep me on track, it's still just a hobby that most people seem to appreciate. Besides, I wouldn't have time to edit out all the mistakes I would make trying to follow a script. That being said, I certainly see your point! Thanks for checking it out!

What's the difference between 'signal aspect' and 'signal indication'?

@MarkClayMcGowan

3 жыл бұрын

The aspect is the color and quality of the signal. The indication is what it is telling you to do. I hope that makes sense! Thanks for checking it out!

@dougkathydavies3024

3 жыл бұрын

@@MarkClayMcGowan Thanks Mark. Love the videos. I'm in the middle of Part 2! I don't now how the train guys keep all of the signal rules in their heads.

You said something about a green signal being clear for the next 4 blocks. What is a block?

@MarkClayMcGowan

3 жыл бұрын

A block is the track between two signals, usually about two miles but it can be a shorter distance depending on the situation.

@jovetj

Жыл бұрын

Block signaling divides the rail line into signal blocks of generally 1-4 miles each. Ideally, only one train uses a block at a given time. Block signals protect the entrances to both ends of the block. The number of aspects of the signal schema determines how "clear" a _Clear_ signal is. Consider two scenarios of signals a train might encounter: [1] Green → Flashing Yellow → Yellow → Red [2] Green → Yellow → Red These scenarios assume no track switches in play along here, too. The first one is a "four aspect" schema, the second is a "three aspect" one. The signals need to be able to warn the heaviest, fastest train early enough so it can stop before the Red signal. If that heaviest, fastest train may not be able to do it between the Yellow and the Red, then another aspect needs inserted. That's where #1 comes from, with the fourth aspect. If four isn't enough for a given location, you can even add more aspects: [3] Green → Yellow-over-Green → Flashing Yellow → Yellow → Red The signaling is tailored to the specific circumstances and needs of the line.

Sis this w Lionel, actual track ckt. one running rail insulated and 6 v.d.c. across it and a relay also. train enters block and relay drops out. I did have a resistor with battery so it would not be a dead short when train entered the block, this could all be hookt up so u could not bend the iron into an occupied block, It would could be hooked so track sw. could not be unlocked.

@Mk99987

2 жыл бұрын

What?

Most automatic signals are permissive, meaning that a red signal is stop and then proceeded at restricted speed.

@MarkClayMcGowan

4 жыл бұрын

I knew there was an exception, I just couldn't recall what it was. I truly count on viewers to make those corrections. Thanks for checking it out!

@jovetj

Жыл бұрын

Permissive Red signals are a complicated matter, believe it or not. "Stop and Proceed" isn't as common as it used to be, as many have redefined that to _Restricted Proceed_ or _Restricting_ or something similar to save a bit more time and fuel. Some railroads have gone back and forth on that over the years, not being able to weigh cost savings versus safety. It really comes down to the rulebook in effect!

All we had was the Red, Yellow, Green ABS in the Rocky Mountain Div.

@MarkClayMcGowan

4 жыл бұрын

Was that SP or D&RGW?

@killsalive1

4 жыл бұрын

@@MarkClayMcGowan The Milwaukee Road Mark

@MarkClayMcGowan

4 жыл бұрын

@@killsalive1 ahh..i need to find a book on that road!

@killsalive1

4 жыл бұрын

@@MarkClayMcGowan "The Milwaukee Road, Lines West" is a great place to start. Email me at killsalive@gmail.com and I can send you a list of what I have and also I can send you my memoirs of when i worked there. In the email put the title Milwaukee so I will know it isn't spam.

Sooo red-stop yellow-caution green proceed normally...sounds familiar..

@MarkClayMcGowan

3 жыл бұрын

Except highway signals have nothing to do with the condition of the road ahead of them, but only that traffic is moving against them at that intersection and do not consider braking distances.

@raylrodr

Жыл бұрын

Yellow isn't called caution, that's only on cartoons and for foamers. Aspect, Yellow: Indication, Proceed prepared to stop at next signal.

You did not mention the Luna signal.

@MarkClayMcGowan

3 жыл бұрын

We no longer use lunar signals on this part of the system but I believe I touched on them in part 2. They were replaced by flashing reds. Thanks for checking it out!

@billmorris2613

3 жыл бұрын

Mark Clay McGowan Does the flashing red signal require a stop? Since it replaced the Luna is it still called a low signal?

@MarkClayMcGowan

3 жыл бұрын

@@billmorris2613 no. It is a restricting signal, not a stop signal. Its indication is "proceed through turnout at restricted speed prepared to stop short of another train".

@billmorris2613

3 жыл бұрын

Mark Clay McGowan So it’s the same indication that is on the EOT / FRED?

@MarkClayMcGowan

3 жыл бұрын

@@billmorris2613 no. The EOT is an operating part of a train. Its flashing red light is a marker light (like the red light on a caboose or the dimmed headlight on a rear helper) not a signal.

Those aren’t seaboard signals?

@MarkClayMcGowan

3 жыл бұрын

Seaboard?

@glennfoster2423

2 жыл бұрын

Seaboard Railroad. It ran along the East coast from just South of Washington DC to Florida. Seaboard and Atlantic Coast line merged to form Seaboard Coast Line.

@jovetj

Жыл бұрын

Correct, they are not. Seaboard uses different rules, and Flashing Yellow on Seaboard means something completely different than it does here!

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FOR THE LAME PERSON LIKE MYSELF ....VERY CONFUSING VIDEO .......DID NOT UNDERSTAND HIS EXPLANATION ...

@MarkClayMcGowan

3 жыл бұрын

There's nothing simple about railroad signaling and not just anyone has the aptitude to figure it out even when they work there, let alone trying to decipher a short primer such as this, so you're not the only one who doesn't get it. You're in good company!. I made this video (and its follow-up) because I was asked to by a subscriber. I tried to make it as easy to understand as possible.