Positive Train Control (PTC) 101 - what even is it? - Railroad 101

[@kenrickman6697]

Class one engineer for 20 years here. I detest PTC, for several reasons. First and foremost, PTC has created an entire generation of throttle jockeys who are dependent of the screen in front of them to know where they are. As one conductor put it to me, old engineers run better without PTC, new ones run better with it. With the exception of information about the signals ahead, the PTC display does not give any information at all which I don’t already know as an experienced engineer. WHEN (not if) PTC does not work, it will create a situation where a supposedly qualified train crew are completely incapable of safely operating a two mile long string of explodey boys, but they’re doing it anyway. Related to that, far too many people rely on PTC as a cab signal system. Even the railroads expect us to use it in that capacity. The reliance on an unreliable technology scares me. With railroads in the Hunter Harrison era cutting back on maintenance and generally cutting every conceivable corner in the quest for profits, it’s likely to create a deadly situation that could have been easily prevented. Finally, I dislike PTC because of its use on railroads not as a safety device, but as a discipline system. For a long time, it was common practice to automatically take a crew out of service after an enforcement, regardless of the reason. There have been several well documented examples of PTC being programmed with the wrong data and then enforcing a crew for doing exactly what they should have been doing. There are numerous little things I can nitpick about PTC, from design to implementation to reliability. While I appreciate the goal of preventing accidents, blind faith in an imperfect technology is making a situation that I fear could be just as bad or worse in the long run.

[@Hyce777]

That's frustrating, but not terribly surprising to hear. It's definitely not a foolproof system, and lord knows looking at the enforcement data the amount of extra enforcement that PTC caused for a software issue is ridiculous. I'd have hoped that engineers were still learning their subdivisions the right way first, but, I suppose this is the easier way out. Not fantastic, that. Almost sounds like old heads and air vs. newer engineers and relying on dynamics.

[@kenrickman6697]

@@Hyce777 In theory, we’re expected to know our territory without help. But given that there is a mandatory track line view right in front of us at all times, it’s virtually impossible to ignore. I’ve caught myself paying less attention to signals since I have them right in front of me, and I learned railroading a quarter century ago. We are mentally lazy creatures by design, and sadly it seems that the people who designed PTC didn’t consider that in their design. Don’t get me started on running with air vs. dynamics! I had to teach myself, and got disciplined for doing so, but to this day those trains I’ve run with air were the fastest and smoothest runs I’ve ever made. I miss the circus trains just for that if nothing else. I loved having a Ringling Bros. trainmaster compliment me on my skills.

[@kenrickman6697]

@@Hyce777 Time for me to get on a train. If you’re ever in the Carolinas (can’t imagine why you might have heard of Spencer, NC), look me up. There’s a meal and a beverage of your choice with your name on it, a railroad man (and sometime model railroader) who would love to talk shop, and a young boy who loves your channel.

[@Hyce777]

@@kenrickman6697 stay safe my friend - and thank you! I'll be back out that way one of these days.

[@ShuRugal]

@@Hyce777 "We are mentally lazy creatures by design, and sadly it seems that the people who designed PTC didn’t consider that in their design." I feel like that's the entire point of systems like PTC - to reduce problems which can be caused by the human factor. Granted it creates a whole new set of problems to solve, but at that point it's going to come down to the numbers game: does the number of problems caused by the new system outweigh the number of human error problems the system solves? I don't have the statistics in front of me, but I would be astonished if PTC were not reducing the total number and average severity of rail incidents. It kind of parallels the discussions around automation in passenger cars. The automation is absolutely going to fail, but the threshold of "better than the average idiot who tries to read a newspaper while driving at 70 mph", the threshold of what constitutes an acceptable level of failure in automation only needs to be lower than the actual overall performance of the manual process it replaces.

[@toslowlypoke]

common misconception. negative train control isn't when you rub a train's face in the oil spill it left on the ballast, it's when you *don't* if it *doesn't*

[@catreader9733]

Ha!

[@musiqtee]

@OP: Oh, we’re well into Hegel and dialectics…? I can dig that (rather than ballast)… 😅

[@toslowlypoke]

​@@musiqtee skinner, actually, but i guess the structure of operant conditioning does map pretty neatly onto a hegelian dialectic, so it's not like you're wrong.

[@musiqtee]

@@toslowlypoke I agree, but I wasn’t sure (smart) how to append behaviorism to the (quite simplistic actually) PTC (ATC here) unit - I got hung up on the OPs (dual) negatives forming a progressive change of observation (not outcome)… 😂

[@morph-]

Good big bang theory reference.

[@BoostedCyclePerformance]

I’ve been a certified PTC installer for 7 years. PTC can absolutely control throttle. Not so much on earlier retrofitted locomotives. But on factory installed units, it can absolutely be fully automated. That’s why carriers are pushing for one man crews. I kinda agree. But the person in the conductor seat should be an electrician.

[@Hyce777]

Interesting! I only ever dealt with modified power. That's not so surprising, thinking about it though. Thank you for the correction! I'd also note that a lot of the industry is *obviously* pushing for automation, but it's nice to see the support from the regulators.

[@BoostedCyclePerformance]

@@Hyce777 You were spot on with everything else. I wouldn’t call it a correction, more of an addendum. Next time you’re in Houston, and have a min, it be fun to look at some cool cars in my shop and drink some beers.

[@Hyce777]

Sold! :D ​@@BoostedCyclePerformance

[@fitzayadventures]

I've only ever seen that with PTC TO blended units and TO can't run for crap. Now a PTC penalty will open the PCS and cut all power but not Dynos

[@84hansennr]

​@Hyce777, you are right about the PTC not selecting throttle positions. What the gentleman is referring to is the energy management system. PTC and EMS have been integrated on the same screen, however they are a separate system from an operating standpoint. EMS is set up by the Engineer separately from the PTC and you can run PTC without the EMS active. PTC, by itself, will not do anything besides provide warning and dump the air if you don't take appropriate action.

[@94_Chevy_Z71]

To all fellow ES&D crew members, In lieu of this video, the Eat Shit & Die will be running under Negative Train Control (NTC). Here are the 6 commandments: #1: The throttle stays on the ceiling AND back wall at all times. #2: The Johnson bar is welded all the way in the corner, because the ES&D doesn't believe in going backwards. #3: Every safety valve is welded shut; the ES&D paid for the whole pressure gauge, therefore the ES&D is going to use the whole goddamn gauge. #4 Speed limits? The ES&D doesn't have time for that bullshit! #5 Forget the f*cking signals! Every train is highest priority on the ES&D. You just need to race the others to the switch, and pray you get there first! #6: Following the Vatican & Southern's example, all express services have 150 pounds of nitrous-oxide on tap in the locomotives to ensure passengers arrive on time, regardless of their condition upon arrival.

[@shimesu443]

Are we still allowed to brawl it out over who gets on the turntable first? Please say yes!

[@azurite1398]

🫡

[@94_Chevy_Z71]

@shimesu443 yes

[@jerrysgardentractorsengine2243]

To quote my own comment: speed limits on the ES&D are merely speed suggestions

[@wesw9586]

Oh hell yeah!!

[@charonsferryold]

The train wreck you discussed is also why if the FRA catches you with your phone on while on duty at any time they kill you in real life

[@ericsundell9978]

It kinda astounds me that it took till post 08 to ban cell phones in the cab. Kinda seems like this would have been a no-brainer several years earlier. I think honestly that was the bigger issue in that wreck, I mean PTC is good obviously, but I think the real culprit here, as is often the case with Railroading is just pay the f*ck attention to what you are doing. Its not hard work, but if you screw it up, the consequences can be disastrous/fatal.

[@ethanwhitehead2085]

@@ericsundell9978 All safety rules are written in blood.

[@charonsferryold]

@@ethanwhitehead2085 For sure, and the more seemingly repressive they are, the more blood was spilled in the ink. At this point I assume a lot of industrial fatalities are caused by either the victim or someone who controlled the victim deliberately tossing the rules aside.

[@skyrianlord2684]

I like to think of the two man crew requirement in the same light as planes. Under ideal conditions commercial planes could be capable of take off, flight, and landing without any human input. However, when things go wrong it's nice to have a pair of pilots to provide educated oversight of the automated systems and reduce the odds of catastrophy.

[@davidty2006]

Hmmm 1 man crews are only really viable for metro systems due to their frequent stops Longer distance trains need 2 man crews moreso passenger trains think britain and europe gets away with 1 man freight crews but our trains and distances are alot shorter and don't end up stuck in the middle of nowhere.

[@bccarl88]

That Thumbnail wreck is also why the FRA banned the usage of cell phones during the operations of the train. For those who don't know, cell phones must be turned off and must be stored away somewhere that is not in or on your persons.

[@cdavid8139]

Many operations permit crews to have cell phones for work related activity

[@bccarl88]

@cdavid8139 yeah. And I'm jealous. But it is cool when get I operate on G&W territories, it's sort of like a free pass. There's been quite a few times when I've had to call a track car or a MOW crew who are 10-20 miles down the main line from us to get permission through their limits. And a lot of those times, they would have to call me back to let me know their crews are in the clear.

[@TheLunarr-TerroPony]

"dont show up drunk" kenosha starts playing in my head xd

[@werta5000]

The missile knows where it is, because it knows where it isn't

[@lonnyyoung4285]

HLC?

[@werta5000]

@@lonnyyoung4285 it is able to obtain the deviation and its variation, which is called error

[@cyndernight2422]

@@lonnyyoung4285 would you intercept me?

[@szymekstormtymczasowe1730]

The missile knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the missile from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position that it was, is now the position that it isn't. In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation, the variation being the difference between where the missile is, and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the missile must also know where it was. The missile guidance computer scenario works as follows. Because a variation has modified some of the information the missile has obtained, it is not sure just where it is. However, it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error.

[@RailrunnerRHS]

Two PTC fun facts from the Northeast: - Amtrak and a number of the commuter railroads use ACSES, a PTC system that relies on transponders placed in the middle of the track, instead of using GPS. I think this was because they wanted to be able to differentiate speeds between outer (local) tracks and inner (express) tracks and couldn't guarantee reliable enough resolution with GPS, but I could be wrong on that. - Strangely enough, PATH (Port Authority Trans-Hudson, the subway system between Jersey and Manhattan) was included in the PTC mandate despite being isolated* from the neighboring mainline railroads. IIRC this was a legacy thing from when the system was the Hudson & Manhattan and actually DID share tracks with the PRR, meaning they fell under the FRA's jurisdiction when it was formed.

[@Hyce777]

Interesting! I knew the northeast corridor used a different system but it's entirely out of my wheelhouse. Cool!

[@Aliceintraining]

@@Hyce777 it would be interesting to see you review other systems. things like the german PZb LZB, and the Japanese ATC-s and ATC-p systems, and the lackluster uk AWS and TPWS. cause I think you could give interesting points on how well you feel these systems work/how safe you feel they are.

[@Alcochaser]

@@Hyce777 The two main systems are called I-ETMS (the one that is mainly used on freight railroads), and ACSES or ASES (The one with transponders mainly used on passenger only railroads). But there are some others. The others being used on some isolated lines, or one.. being carried over from a system that existed before PTC, but qualified as being PTC.

[@brianl3270]

PATH utilizes Communications Based Train Control, a similar product utilized by MTA New York City Transit on their "L" Canarsie line. (I helped commission that system to bring them into compliance by the 2018 deadline in my previous job). The ACSES system also doesn't have a dependency upon the GPS resolution...something that came to light awhile back where the entire I-ETMS system came to a standstill, but the Northeast corridor trains were still able to run. Tunnels areas come to mind where GPS can be problematic. -An ACSES-II PTC engineer

[@hannahranga]

​@@Aliceintraining while the UK systems are more limited in scope they've been around and functional for a lot longer. Imho as an outsider from a RR that uses a transponder based system the implementation of PTC does seem to be a good example of perfection being the enemy of good enough.

[@alexanderbeck5063]

We gon' learn today.

[@jerrysgardentractorsengine2243]

Hyce, I just want to thank you for this video. My dad and I have been confused about the inner workings of PTC for a while now and you basically answered all of our questions. I have a feeling he’s going to appreciate this just as much as I did

[@ClearTrackSpeed]

I actually knew the engineer on the Chatsworth collision. Yes, he was texting at the Chatsworth station, but he had forgotten the signal before hand was a restrictive signal, and the conductor didn’t remind him. The final signal before the track went to one line had malfunctioned showing green when it should’ve been red, unfortunately the UP freight had just cleared the last signal before the double track so when Robert ran the red, there was no way of either Crew, knowing that they were gonna run into each other. another interesting thing about PTC is that my line the Ventura in Santa Barbara subs were the first part of the country to be fitted with PTC

[@Hyce777]

Ugh. Horrible. I'm sorry for your friend.

[@kenrickman6697]

Thank you. I’ve long felt that there had to be a lot more to the story than just “Texting is bad, mmmmay?” As a lifelong railroader, I’m not about to defend the use of electronics on a train, but I feel that texting became the scapegoat and nobody bothered to look into a more nuanced explanation of the situation.

[@michlo3393]

The control point was lined AGAINST the Metrolink train, the dispatcher cannot set a route or even request a signal in that condition. And this idea that there was a "false clear" is untrue. Shunt the rail and the signal defaults to red. And it WAS red, the guy ran a red absolute. Why? who the hell knows. Probably because as a commuter engineer you not only get used to doing the same things at the same places but you expect clears wherever you go. The meet they were making was usually at a different spot. Running on an approach, making a station stop, texting on your phone, blowing for crossings...etc are all distractions that get in the way of remembering that you're running on an approach. It's not rocket science. The engineer was just distracted at the worst possible moment.

[@FabiaLp]

Steam locos in Germany have basically a brake cylinder connected to the throttle lever with a over pressure valve, so if the brake pipe drops below max application it will close the regulator really quickly to about 5% (minimum steam flow for lubrication and to not draw a vacuum)

[@Hyce777]

That's really cool!

[@Davids_Hobbies]

This was a super fun and informative video! I know we all love the "PTC could have prevented this" memes but having a more serious video talking about PTC was excellent! Where I live in New Jersey, we have a very small freight railroad called the Morristown & Erie that doesn't have PTC installed in their very small roster of locomotives. They run along a stretch of track that NJT doesn't use but sometimes they have to run on the Morris & Essex Line and they have to run with a NJ Transit engine on the front that does have PTC. They also have an exception to run excursion trains at the Whippany Railway Museum (Which you should come and visit btw! They have some super cool stuff!) without having PTC (or a NJT locomotive on the front) even though there are several crossings on the line. (Like you mentioned in the video in relation to steam locomotives not having PTC, there are workers stationed at each crossing to make sure that the crossings are clear.)

[@peregrina7701]

Thank you for the video! Very informative. I never in a million years thought I would hear the words "navigation by dead reckoning" applied to a _train._ Ye gads! Fun to learn today!! :)

[@NullReference119]

Honestly it makes sense, wheelslip aside the tracks are pretty well laid down. What I'm surprised is the railroads don't just have the work crews just clip a bar with a resistor between rails. That would trip the track circuit and mark that segment as occupied.

[@briannem.6787]

I think that every safety system that can compute a safe stopping distance has some form of dead reckoning. That is, all but the simplest train safety systems worldwide. Things like the UK's AWS can't tell the train to stop in so many metres, but the Germans had such a system in at least the 60s, which did need a little mini-computer to do all the numbers onboard. I say "Germans" because I think that both east and west had similar systems, because it started development before the wall was started, but it's been a while so don't quote me on that bit

[@jorgen3]

In Europe it is called ERTMS ( European Rail Traffic Management System ) It not using Gps. It uses Position Balise and the locomotive's distance counter to calculate the exact position of the train Level 1 (with signals and fixed transponders often just at the signals) Level 2 (without signals/or signals but continuous data transmission via GSM-R ) Level 3 (without signals and track management continuous data transmission via GSM-R Moving block)

[@davidty2006]

Britain uses AWS and TPWS systems that one can see in the gauge.

[@kornaros96]

Tempi rail crash flashbacks...

[@dkbmaestrorules]

The difference between Level 1 and Level 2 is not whether it has lineside signals or not; it's the mode of data transmission. Level 1 has intermittent transmission (i.e. only at fixed transponders), Level 2 has continuous data transmission via GSM-R. And you can have lineside signals on Level 2, although you don't have to.

[@sniper.93c14]

@@davidty2006 they are less sophisticated, but they get the job done. TPWS can work at any speed and conditions theoretically.

[@davidty2006]

@@sniper.93c14 long as there is electricity and enough distance to stop.

[@teknikal_domain]

Now that my job places me in very close proximity to the rail industry (well, auxiliary to. I'm railway taxi - drive crews from their train to hotel / yard / other train / whatever), maybe now I'll start to understand what's being said when the crew in the back starts griping about PTC! I love your videos. I'm the type to google everything I can find and yet yours always teach me something new, even if it's something I thought I had well understood. And now that I'm interacting somewhat with the industry on a daily basis, it's more than just trivia knowledge. You don't really gain an appreciation for everything until you're dealing with it up close

[@TravisCyprien]

Thanks Hyce, as a Railroad Conductor currently this is exactly what PTC does. It’s not Full proof but it’s a backup. Still as a conductor I still have to know my territory and use the timetable charts and know where Quiet Zones are or speed restrictions are at to let the engineer know. Can’t be over speeding going into a siding. When there is a restricted speed going In or leaving out. Sometimes PTC does crap out on us so we have to follow through timetable and get word from Dispatch. But it is what is.

[@AlexBaldwin440]

The problem with PTC is the class one railroads use it to terminate employees. It is a good thing for safety but once you get a 30,000 ton coal train with 2 seperate sets of DP and they want you to use Trip optimizer, and it starts to speed, but they don't want you to disengage TO until it prompts you to take control and by the time it does that you're enforced by PTC for speeding and then they pull you out of service. Point being is PTC just becomes another thing the engineer has to monitor on top of all the other things that are controlling the train makes it very difficult. The conductor can not even control PTC.

[@KaneYork]

Management is getting incorrect training

[@kenrickman6697]

Who says management gets any training at all? As far as I can tell, they’re hatched out of an alien pod already perfect.

[@jeffhergert4614]

I had a situation like this. LEADER in auto throttle got speed to fast approaching a speed restriction and PTC caused a penalty application. I reported the incident as required and never heard anything further. My employer doesn't want to know when their systems screw up.

[@web1bastler]

Greeting from PZB90, LZB, ETCS land :p

[@0ptera]

You forgot a good dozen ones. Thankfully ETCS will finally unify it, somewhat.

[@m0llux]

​@@0ptera he pretty much mentioned all the train control systems currently in operation in Germany, except ETCS. Oh, except one, which is the Fahrsperre at the Berlin S-Bahn. Essentially, it works by installing a movable little arm at signals, which, if the signal is red, will extend. When a train then comes by, it literally opens the main air line, emptying it, thus applying all the brakes.

[@MrMarci878]

​@@m0llux when mentioning Berlin you have to think of ZBS as well

[@markdebruyn1212]

The Rotterdam Metro uses the LZB system too

[@johnbrown9181]

@@m0llux The London Underground has had that tripcock emergency stop system for a long time as well. I'd assume it's probably been reinvented quite a few times.

[@makostesztakft]

Thank you so much for discussing augmented GPS (cellular A-GPS not explicitly, but odometer comparison). I straight-up wrote my Internal Assessment in IB math on a very similar problem and it was for a rail transit application too!

[@QuorkQTar]

Thanks for the informative video. It really is fascinating to see how different the philosophies are across the pond as to what is wayside and what is trainside problems.

[@rshackelford4445]

As someone who is waiting on the email to go to Georgia and train to be a conductor For Honse Sufferin this video is very helpful and gives me a better idea of how a system I'll be working with daily if i pass all my exams works and how it came about.

[@osageorangegaming5128]

I'm really loving these 101 videos you do, Hyce- its easy to go down the rabbit hole of 'Topic X' and learn something more thoroughly if its not really known by the general public or even just smidge more of something already basically known. Even better is getting to rewatch them- having that better understanding of the topic at hand and related content- and how it lives up to your goal of demystifying historic and modern railroading. I can't thank you enough for doing vids like this.

[@Hyce777]

Glad you enjoyed and learned something mate!

[@morph-]

In the UK we have two systems, AWS and TPWS. They work together to stop trains if the driver isn't paying attention (This is excluding the dead mans switch that stops the train if the driver hasn't responded to a random beep in cab). The way AWS and TPWS works is that when you come up to a signal, displaying "caution", "preliminary caution" or "danger", an electromagnet on the ballast below the train will be energised, this in tern will be detected by the train and will set off an audible and visual warning in the cab. It doesn't tell you what the warning is for so it forces the driver to look forward and pay attention to what the system is warning you about. You have to acknowledge the warning within 2.2 seconds or it puts the train into Emergency breaking. After a failed AWS acknowledgement, a driver must contact the signaller in order to get permission to isolate / reset AWS and reset emergency breaks before being able to move off, and they generally have to explain why they missed the AWS acknowledgement. These electromagnets are also in place for upcoming speed restrictions and other such hazards. We don't have them for things like crossings because it is expected that a signal will become "danger" should a crossing be malfunctioning, and as such the AWS will respond accordingly to the red signal. However this is just scratching the surface as to what safety systems we have, as well as things like in cab signalling for high speed lines etc. TPWS also does things to make sure you aren't over speeding by too much but I'm not too familiar with that side of it so i decided not to even try and explain that part. Oh, and every mainline train in the UK has to be AWS capable, but it's pretty easy to support.

[@YourLocalRailfan]

I love how easy it is for me to understand your videos

[@patricksheary2219]

Hi Mark, an excellent and fascinating tutorial about PTC. If I were an engineer, I would appreciate this as a safety tool that, as you said Mark, has my back. I didn’t realize just how integrated it is with the railroad systems. Quite an awesome bit of electronic engineering. As always Mark, I learned much from this clear and succinct discussion. Many thanks for making another great 101 video, I so look forward to watching them. And as always cheers to you Professor extraordinaire!

[@eisbaer6]

As a train driver in Germany reading about train crews getting into trouble for an intervention seems like some sort of distopian fiction. Over here we´ve had some sort of train control on every train since the 80s and on every route since about 2012. I´ve been driving on my own now for about three years and I´ve had so many interventions by PZB alone that I couldn´t even count them, if I wanted to. (Some were due to equipment failure but most were caused by me not braking enought or otherwise being stupid, but nothing serious ever happend. Stuff like passing a signal at danger after being authorised to do so but forgetting to actually override the train stop.) Being suspended from driving after every single one seems insane to me. After 2 weeks we wouldn´t have any train drivers left operating.

[@Skullair313]

I think what they get you for is speeding. Althpugh, there is a central analysis office, that regulary checks TRU data to check driver performance. After a dangerous event they will also scrutinize you.

[@garysprandel1817]

Thanks for clearing up the mystery for us laymen Hyce Grew up along and still live within earshot former CNW UP Janesville sub so I was familiar CNW's ATC that was why foreign power was always trailing and never leading when it was a CNW through route to the Twin Cities. Even under PTC the ATS system remained in place for some reason so for a couple years it was assured any of the very sparse freight traffic would hsve a pair of former CNW SD40-2s on point. Needless to say once the ATC was finally taken out of service a few years ago it was very odd seeing a grain extra come through town with a pure KCS consist

[@tobiandobito3736]

I play train sim world so I leaned it from there. I am more used to PZB, Sifa, AWS, AFB and the LZB one. Though I have one route that has PTC. Edit. For those curious I will explain what each does to the best of my ability. Take what I say with a grain of salt. I learned this from a game and wikipidia. I don't have any real life experience. Lets start with the 2 that are similar to what Hyce is talking about. PZB and AWS. First PZB. PZB or Punktförmige Zugbeeinflussung is basically a the german exuivaliant of PTC, but it runs differently. PZB tells you about yellow signals, redsignals and if there is a lower speed limit. The way PZB runs are by magnets on the rails wich are usually by signals and lower speed zones. There are two main things that tell you what to do in PZB. There is a 2000Hz magnet, 1000Hz magnet, and a 500Hz magnet. The 1000Hz magnet is usually before caution signals and lower speed zones. There are a few things you can and or must do when encontering a 1000Hz signal. There are three levers on trains with PZB. There is PZB acknowledge, PZB release, and PZB override. When you get the signal you HAVE to acknowledge it in 2 to 4 seconds. If you don't the train WILL come to a complete stop using emergency brakes. Once it's at a stop you can the move again after pressing acknowlage. If you do hit it in time then you will receive a message saying slow down to a certant speed before 23 seconds. after about 1250 meters (used to be 700) you can release the speed restriction only if it is safe to release. The most common place for a 1000hz is again before a speed drop or if its a yellow signal wich may be followed up by a red signal. That brings up the 500hz magnet. About 250 m before a train aproches a red signal it will receive a 500hz magnet. This is a forced speed limit and going over it will cause an emerganicy stop. Idk if it's like this in real life but it asumses your going atlest under 55 kph. over that and it will stop you now mater what. Even if you just entered it. These are found always before a red signal and makes sure you are going slow enough to stop before said signal. From my experience you cannot release it until you are passed the signal when its green or yellow. Lastly is 2000Hz. This one I have the least amount of experience with because its a magnet after a red signal. In train sim world if you pass a red signal any amount it fails you and you have to restart the mission. But from what I understand it's a emergency stop signal. It automatically. Next we have AWS. Its baciacly a dumbed down version of PZB. It mainly runs in the UK. I its just a sound that buzzes everytime you cross a yellow that you have to press an acknowledge button for and a flower like light will turn on until you pass a green. I think it also stops you when you pass a red also but I'm not too sure on that. After that is LZB. You can have PZB with LZB, but you cannot have LZB without PZB. Altleast to what I know. From what I can understand LZB is just automation for high speed trains. The literally automate the driving part. Even the PZB stuff. After that we basically have cruise control or AFB. Its just cruise control. There are two ways to turn it on. When your at a stand still you can just turn it on at 0kmp. When moving you need the throttle off and the cruise control set to max speed. Then you can turn it on. Set the speed and then set the throttle. Lastly is Sifa. Sifa is just an awareness procedure also in Germany. It periodically sets off an sound that when heard you have to press a switch of some kind to acknowledge it. If you don't in time the train will have an emergency stop, BUT unlike the other systems if you acknowledge it even after the alarm and then reset the throttle you don't have to come to a complete stop. Not every country has these and if they do they may be named differently. I am just more familiar with the German and UK systems because that seems to be the most popular route typse in train sim world 4. That and Germany is very stricked about all that. Again take all this with a grain of salt. I have knowledge from a game and wikipidia. I've got nothing compared to what the professionals know. They know this for a living.

[@nether_bat]

AWS/TPWS is a bit more sophisticated than that. AWS is used to warn the driver of yellow/red signals. Every signal on the UK network (excluding HS1 and platforms that can only be accessed from HS1) have an AWS transmitter fitted before the signal that emits a magnetic field if the signal is displaying anything other than a solid green aspect. This is detected by a receiver mounted on the leading bogey of the train, causing an AWS warning that will apply the emergency brakes if not acknowledged. The sunflower lights until a green signal to remind the driver. TPWS is used for train protection. From an infrastructure perspective, TPWS and AWS are very similar. TPWS emitters work in two modes. In overspeed mode, the emitter will apply the trains emergency brakes if the train is travelling too fast to stop at a red signal or slow down for speed limit. In train stop mode, the emitter will apply the trains emergency brakes if passed at all. TPWS can also be used to protect buffers. A third system called ATO is also used in the UK, but it has not been expanded past its trial sites on the WMCL and Chiltern Main Line, and operates alongside AWS/TPWS

[@kathysexton4554]

What happens when the switch is in the wrong position? June 7th 1973, Eckman, WV. My father as conductor in the engine with the engineer. Freight train, N&W The switch was thrown and Daddy's train was directed towards a stationary train. Head on collision, the stationary train caught fire. All of the articles say no one was hurt, however, my father's back was broken that day. I was fortunate enough to purchase an original photo off of Ebay of the wreck and some of the locals grabbed some photos that day as well. One of my very first memories is "helping" my mother nurse my father back to health.

[@tedherman38]

Great video! I worked on the initial implementation in the locomotive facility in the Roseville yard in 2014-2015.

[@thomasdecker7631]

Clear back in the 40's, Pere Marquette was using ATS (Automatic Train Stop). The FRA ordered the 1225 crew to remove the no longer functional hardware. I assume ATS was a neanderthal ancestor of PTC?

[@Hyce777]

Essentially yeah. Usually based on mechanical trip stops tripping a brake valve.

[@dknowles60]

and ats was a lot better

[@Zimmzamm]

CFRs mentioned. Church of Alco shall be summoned

[@FineApe]

So the Train knows where it is because it knows where it isn't.

[@matthewmiller6068]

I'm interested in hearing more about steam because many have claimed PTC is one of the reasons that the N&W J 611 can no longer run mainline excursions since "there's no way to put it in a steam engine". We know they'd got exemptions for ditch lights but seemed odd they couldn't have something like that for PTC given all the things you pointed out (and then also usually extra precautions and security along the route to keep people off the tracks who want to see it)

[@NBSV1]

The managed to put PTC on the BigBoy so it’s possible for a steam train. It’s likely just so expensive not many are going to bother. I think one of the big issues with BigBoy was getting good battery backups for everything since the dynamo wasn’t reliable for powering it all.

[@landonbeatty6262]

5:58 like sending jersey to the house track

[@Hyce777]

I debated putting that clip in

[@landonbeatty6262]

We love jersey though great video Hyce thank you

[@NarbonneGauchoBoingo]

Great job explaining this Hyce, thank you!

[@MatthewMello]

The territory I am qualified on, I get to use both the I-ETMS and ACSES systems. I love the I-ETMS much better than the ACSES. ACSES is great for passenger, especially commuter, as there is no entering information into a computer about your train. But, for friend, that does stuff like switching and reverse moves at switches and interlockings, yeah, it doesn't work well. There is no "restricted mode" like I-ETMS has. Also, it is programmed that every freight is a 15,000 ton all load train (maybe exaggerating a little) where I-ETMS performs according to your current train consist that is entered into the system. After watching to the end, adding a few more things. 1) You didn't mention about PTC not being able to stop a rear end collision. Right now, there is no way to communicate where the rear of a train is. 2) You mentioned 21 in a 20 will cause braking. PTC won't enforce until 5 over except for the upper limits of restricted speed, then it will enforce at 20 mph. 3) Another thing it does, it starts blowing approx 20 seconds before a crossing (not sure of the exact number of seconds) 4) As far as problems, we had numerous in our cab signal territory. It still isn't perfect. When the Cab Signal drops to restricting, we have to be prepared to stop at the next Cab Signal Box or Interlocking fixed signal. PTC wants you at restricted speed now and will count you down to a penalty brake. If you're running on an approach in the cab (remember, the cab signal aspects just dictate max speed), you want to start slowing down before the next box where it drops to a restricting.

[@Pamudder]

Thank you for your typically wonderful explanation.

[@SternLX]

You touched on communications. Fun fact: CDMA, one of the very first telecommunication protocols for Cell Phones was primarily invented for transportation logistics(started with studies for Ships in the 1950's at MIT). It ended up in the SPRINT Telephone Network. Sound familiar? It should, Southern Pacific Railroad Internal Network Telecommunications.

[@NathanielStauber]

Trains, aircraft, road vehicles, and watercraft are all trending towards systems that inform operators or act independently when an unfavorable situation is predicted to occur. The current feature sets, level of implementation, and maturity of the various systems leads me to believe that the teams don't talk. Complete interoperability would be interesting. A mesh of every powered conveyance could relay important train or truck information through passing cars

[@jefftanner4301]

Love your content I'm addicted to locomotives since I could walk your videos are amazing it's great to get knowledge of how railroads run and what it takes to run them thank you for the great work

[@andywomack3414]

There was a system developed in the 1930's that could sense when a train passed an approach signal and if some action was not made by the engineer such as reducing the throttle or setting brakes the engine would do that automatically.

[@thomasboese3793]

This was fun. I understand that Ed and the crew at UP got PTC working on the 4014 so she can go off on photo ops by herself without a backup diesel ruining the photos. PTC on MOW? I see the need, the last week the CN has been working on track renewal with a focus on a junction turnout and a road crossing at the same time. The work crews have a set time to occupy the work zone, but that doesn't always mean the job is done on time. Several days in a row I've seen a train stop because of a MOW vehicle was still on the track. Single-track territory has to be a scheduling nightmare at times.

[@david-st8pu]

Clear and concise. I retired long ago but PTC would have been welcome then as well, especially at slide fences

[@Hyce777]

No kidding. Just for the slide fence detection as peace of mind...

[@crusaderanimation6967]

"The train knows where it is by knowing where it isn't..."

[@ImperatorSupreme]

Fun Fact - the Amtrak 91 Collision in Cayce, SC happened during a signals suspension to Install PTC. People claimed PTC would have prevented it. I have yet to find anyone who could adequately explain how PTC could have prevented an accident while PTC was intentionally shut down for maintenance.

[@kenrickman6697]

Really? It’s not exactly rocket surgery. PTC -being active- could have prevented that situation. That’s the whole point. Are you genuinely confused by that, or just being obtuse or pedantic?

[@jackr2287]

Lot of information here. I think as a result I have vaguely determine that my hometown mainline probably had PTC isntalled on it, but the sidings for serving the coal power plant and particle board plant probably didn't...

[@toymachine2328]

11:19 "...the back office that knows everything..."

[@zenontrainstrucks9433]

Great video! Learn a lot!

[@Alex-jf9ij]

Hi Hyce great video bud keep up the great work 😁😁😁👍👍👍

[@kg-Whatthehelliseventhat]

HYCE!!!! Whats up big bro, Hey just wanted 2 thank u 4 ur reply few months ago. I was going thru it n u made my day. 😊😊 Let me know if u make it to Japan. U would love our trains!!! C ya 😊😊😊😊😊😊😊

[@southernohiorailroaderYT]

it knows were it is, beacuse it knows where it isnt, and were it wasn't and were its needed to go -GUIDED MISSLE

[@fsj197811]

Interesting and good video. Thanks for sharing.

[@3bydacreekside]

If it's designed to save lives and actually saves lives? I'm all for it ❤

[@rjstandland4459]

That is a lot but i learned way more than i was expecting

[@HimboJimbo]

Come now Hyce, we all know PTC means Pet The ChooChoo

[@233kosta]

Aircraft autopilot systems have been capable of handling the entire flight for some time now. Pilots aren't going anywhere. "Futurists", tech nutters and other people with a compromised judgement & dim view of humanity will always insist that automata are "better" than humans, but the fact of the matter is that good automation only ever compliments humans. It does not replace them unless they _want_ to be replaced (i.e. Roomba), but even then it's not always capable enough.

[@BeckaReus]

I have always wondered why the IHB and BRC in Chicago are not required PTC. They both transportation PIH and TIH tank cars. On BRC it exists only between two interlocking locations [Belt Junction and 80th St] where Amtrak and Metra cross the BRC. On the IHB it doesn’t exist at all. They were required to put split rail derails at CP Ridge and CP Canal. Both of those plants have diamonds that passenger trains cross.

[@hooverfarms]

15:09 the “missile” knows where it is because it knows where it isn’t

[@fitzayadventures]

We used to have to stop and turn off PTC before we could enter one of our sidings the grade was too steep, and you had to get too close to the signal for PTC to cope with it.

[@shawa666]

The train knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the missile from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position that it was, is now the position that it isn't. In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation, the variation being the difference between where the train is, and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the train must also know where it was. The missile guidance computer scenario works as follows. Because a variation has modified some of the information the train has obtained, it is not sure just where it is. However, it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error.

[@steeljawX]

So many memes are popping into my head and none of them are the one you mentioned. Namely the one from Anchorman, "60% of the time it works everytime." And trying to wrap my mind around this I gave up and defaulted to "The Missile Knows Where it is." ( just youtube search it for the original like 70's audio for the Air Force's video on them trying to explain how their radar guided missiles worked.) It can be translated over to this though. "The Choo-choo knows where it is because it knows where it isn't and it knows where it isn't because it knows where it is." You'd just need to go find it for the entire garglemesh that is. It makes sense if you're able to comprehend it, like calculus, but what it actually benefits you personally in your life........Can't think of much.

[@00Zy99]

@18:00-Hey! That looks like Philadelphia 30th Street.

[@CrowDawg11]

PTC absolutely does not prevent train-to-train collisions, just ask NS. We just had a major derailment a couple months ago where a train running on PTC ran into the back of another train running on PTC that was stopped on the mainline. There's been several more minor ones within the last couple years. It doesn't tell you where the back of a train is, and it doesn't enforce you if you're running on a restricting signal, it will only enforce a stop signal, speed violation, or track authority violation. It also doesn't necessarily stop you from traveling over a misaligned switch or derail, if those aren't electronically connected to the system - which not all of ours are.

[@Hyce777]

Yeah, it's far from a perfect system... Lots of nuances still to sort out.

[@MatthewMello]

It does enforce you if you're running above the maximum threshold of restricted speed. Basically, you can rear end another train at 19mph.

[@CrowDawg11]

@@MatthewMello well yeah, I said it will enforce you for speeding...but it isn't going to stop you from hitting another train

[@BeckaReus]

They are talking about connecting EOTs to the PTC system. The idea is that it would know where the rear of a train is. It would probably enforce the 30mph speed restriction for not having a working EOT. But, like the rest of PTC it just is just smoke and mirrors. On other subjects, I wonder if PTC is the reason why track equipment and hi-rail have to request their limits on a device in their equipment on CSX. The dispatcher can no longer give them permission without a request from that device. We hear all the time the dispatcher telling Track Inspector Blah to request it from location 1 to location 2 on track blah.

[@BandanRRChannel]

The original implementation date was end of 2015, but as the date approached it became very clear that, for various reasons (mostly not related to alleged feet-dragging by railroads), the date was totally infeasible. At that point it was pushed back to tghe end of 2018 or 2020; IIRC there was some rule about "if you're on track at the end of 2018 to get it done, we'll give you two more years, otherwise we'll start penalizing you in 2019" or something like that. The big advance I had heard about at the time for "PTC 2.0" involved "moving block signals" and possibly replacement of wayside signals. As mentioned, PTC enforces existing fixed-block signal indications, and is overlaid on top. A future system might just put all the signals in the cab, with nothing on the wayside. This means the "signal block" would move along with the train, instead of being based on the train moving past fixed positions. This would also allow for tighter train headways; no need to slow down for a signal that'll change as you approach it so long as you can match pace with the train in front of you, and stay far enough behind that you can stop if it does. I don't know if that's still a future goal for PTC.

[@Hyce777]

Continuous block is definitely a long-reaching goal for many, but I doubt it's a part of the up and coming PTC 2.0.

[@Shadowtiger2564]

I do wonder if theres a trend starting of putting them on steam locomotives since Canadian Pacific 2816 and UP 4104 have had those systems added on board. Over un the shop for 576 theres been discussions lately on it though mostly just wondering how those other steam locos are implementing the system

[@Hyce777]

It'll be interesting. If folks want to play on the main....

[@jonathanbarker71]

UP 4014

[@ivovanzon164]

For steam locomotives: Germany still has Indusi as the main backup for everything as that is not depending on any other fixed infrastructure besides the passive inductors. The Dutch system was created after the last steam locomotive left the scene. There is a version that can be used on steam but it probably ties in into the existing Indusi actuators.

[@94_Chevy_Z71]

Commandment #7 of Negative Train Control (NTC): Instead of fusees, conductors and/or brakemen will drop a motion-detecting C4 explosive, with a fuse-like warning light. Ignore these new warning devices, you can kiss your ass goodbye!

[@chief1b]

Great video thanks for the information. Cheers!

[@jruonti]

Just fully automating stuff seems "easy" and "coming soon" but just think about it. If let's say on a train for some reason a breakhose comes undone. A crew can go look at it, re-attach it and keep going. A computer can just sit there sending digital farts about breaks stuck, send help. Not to mention other issues humans can solve.

[@SchrottiJr]

Railroad could look up to the skies for a better version of PTC. TCAS works pretty good if you ask me.

[@Hyce777]

Dumping the air on a plane sounds like a bad idea.... Lol

[@SchrottiJr]

@Hyce777 Yeah, but every plane knows what every other plane is doing and where it is in closer proximity and will steer accordingly if the pilot doesn't react to its callouts. Our intercity express trains in Germany can align switches for overtaking and collision avoidance if dispatch misses something.

[@Hyce777]

@@SchrottiJr makes sense. That's basically what PTC attempts to do in a rail context.

[@FuelFire]

Ah, that's the thing 4014 got in order to be able to run without a helper diesel? Interesting

[@mafarnz]

I’m curious about two things. 1) what are the exact requirements/restrictions on inhalation hazard, especially anhydrous ammonia? Our interchange partner is a class 3 shortline that runs quite a bit of AA but isn’t required to have PTC. 2) In theory could PTC be implemented on a line that doesn’t have any signals? The system could still enforce switch position, crossings and train position based on authority (mile post A to B for example).

[@zaklex3165]

As Hyce stated there are exceptions, one of them being the fact that the line you interchange with is a Class 3 and not a Class 1(Class 2 don't have PTC either unless they also have commuter or intercity passenger trains on them).

[@Hyce777]

For 1) - check 49 cfr part 236. It's a very fun read... Lol 2) I'd figure it could, yeah.

[@jeffhergert4614]

Part of the requirement takes into account how much traffic a line sees in a year. We have branch lines that handle anhydrous ammonia for agricultural use that doesn't have PTC because the yearly amount of all traffic is below the threshold.

[@PowerTrain611]

Something interesting about our railroad and work culture versus what is done in Japan is that the Japanese make sure that the people who operate the trains are operating under and enforcing the rules more effectively. We have to use technology to make sure that happens instead of making training more effective, because that takes timez and time is money. I suppose you could argue that our systems are much more vast and our workforce matches proportionally. I still find it to be a bit ironic.

[@Hyce777]

Definitely. There's a huge cultural difference for sure which plays a role too..

[@PowerTrain611]

@@Hyce777 Agreed. Japanese culture has always fascinated me, and I started learning the language earlier this year. But you're supposed to be on vacation, sir!

[@DADeathinacan]

PTC is great when it works. How does PTC work? Judging by my local railroad... Poorly. When you have a PTC hit at a given location given to every train that passes, for weeks on end, for no reason anyone from train crews to dispatchers can find..? Well, hurrah for PTC, can we get it working better please?

[@captainkeyboard1007]

Nice presentation!

[@Joeybagofdonuts76]

If PTC is anything like Electric Logs. And if FRA is anything like the FMCSA. The manufacturer of the PTC are self certifying. Meaning the manufacturer says "yep, we meet the regulations"

[@lordsherifftakari4127]

one item I could see as an added Failsafe

[@zaklex3165]

If that happens they actually have to switch the lead and trailing locomotives around...so that the one with the failed unit is now the trailing unit and the working one is now the lead unit.

[@Hyce777]

Yeah unfortunately PTC doesn't MU in terms of computer to computer, so you can't have a trailing unit run it. Swapping them around works though! Happens plenty of times. It's why you'll typically see two forward facing units on high priority trains in a row.

[@zaklex3165]

Rio Tinto has only had 2 derailments since they implemented fully autonomous train operations a few years ago.

[@Sunset4Semaphores]

PTC is why all the interesting, obsolete signalling tech is being removed from American railroads. I hope the Colorado railroad museum is enjoying that newly acquired wig wag... PTC and federal money from the 2020 Cares Act for implementation of PTC is why it was removed.

[@Hyce777]

Interesting! I didn't realize that was the background behind that. We do love the wig wag and it's prominently displayed and operating.

[@C.J.1994]

I do have a thought about when it comes to adding PTC for maintenance equipment. Instead of equipping every piece of equipment with its own system, why don’t they implement some sort of “blocker” unit at both ends of the work zone? Something like a locomotive or a hi-rail truck to trigger the system at each end should be able to trigger the system, and effectively shut down the tracks for worker safety, as well as providing a physical barrier or obstacle before the work zone. I would imagine it similar to how a road is shut down for repair work, with a Scorpion blocker truck protecting the workers in the roadway. I could be missing something, but it makes sense to me

[@makostesztakft]

You know, I'm not sure where ACS-64 number 600 is going to get without a wire overhead, but coal is conductive so I guess it works!

[@thestainmorephoenix8632]

Funny thing-we've had PTC for a long time before Chatsworth. 103 years before in 1905, the UK's GWR gave us ATC, which applies the brakes if actions aren't taken.

[@Hyce777]

ATC and PTC are similar in concept but extremely different in implementation. The US has had many varieties of the same on many alignments, for probably as long as the UK has as well. Just wasn't required, nor as "sophisticated" (complicated).

[@Northweasterner]

Electromagnetic ATS has been around here in the states since the mid-1920s. It’s a far more rudimentary system compared to modern PTC.

[@davidty2006]

ATC? is that a older system before AWS and TPWS? Edit: huh it is the predecessor to it... electric signal from a ramp between the gauge gets sent to the train saying if the signal is clear or if at danger sounds an alarm in the cab which forcess the brakes on if not responded to in a set period of time...

[@jeffhergert4614]

@@Hyce777 ATC, ATS, and plain cab signals only enforce signal indications. They don't enforce speed restrictions, work zones or main track authority limits. Interestingly, PTC will allow a train to report itself clear of its main track authority/track warrant limit when it isn't actually clear. It's happened a couple of times on the railroad I work for because the crew made an error of where the rear end of the train actually was. PTC immediately made a penalty stop and lets the appropriate managers and dispatcher know of the violation.

[@Suppagappa]

As far as I’ve understood it, workers are, generally speaking, lazy and stupid. What keeps the train driver from over-relying on the PTC and keeps them paying attention to the track if the PTC will (theoretically) do all that for them?

[@Hyce777]

Penalty applications almost always stop you, so, frequent stops. :)

[@bowserjrrules8162]

Hmm, I don't know about the lower 48, but in Alaska we use a track warrant and not a form B. And its only between control points. An example: "Work between CPF040 and CPF084 on M"

[@Hyce777]

Interesting! Yeah, that makes sense for you guys up there. PTC would still be able to enforce it.

[@bowserjrrules8162]

@@Hyce777 Part of the reason we have such a method is that only short spots on the line even have Signals; most of the railroad requires the use of track warrants for locomotives.

[@Johndoe-jd]

So I have a Railroad question: what does the railroad do with the old wooden ties?

[@Hyce777]

Great question. No idea.

[@Johndoe-jd]

@@Hyce777 I was hoping for a it depends. I thought that if it can not be used anymore on the main it might be used as a replacement for the yard/shop like old rail but I could be wrong.

[@CJ-jo6do]

Most are collected and sold to landscaping contractors or used on MOW trackage.

[@KidarWolf]

@@Johndoe-jd In the UK at least, they sell them to lumber companies that check them over, see if any are safe to re-use for other projects (e.g. garden bed building, path laying/borders, etc.) and resell the good ones. The bad ones that are clean but clearly fractured or damaged, they basically mulch them and use it as wood chip (often used in landscaping, occasionally as playground safety cover, though this is being phased out in favor of rubber matting that has more give in the event of a fall).

[@jordonfreeman166]

I can answer that: the ties get sold to home improvement stores to be sold to homeowners to be used for exterior home decorations, such as retaining walls (my house has a retaining wall made out of old railroad ties), the perimeters for gardens, and several more examples. I worked at a home improvement store for a few years and we sold old railroad ties in the garden section.

[@Streaky100001]

So, on the subject of automation, the UK has run automated trains in London, on the Docklands Light Railway, since the late 80s. I understand early on, in the first 5 years or so, there were some issues, but it's been pretty reliable since. I'm not, of course, suggesting that this means all trains should be automated, clearly there's a variety of use cases for a railway/railroad, some of which will be more appropriate for automation than others.

[@GreatNW]

Ok I watched the whole video and I understand the safety overlay idea and that there are mandatory 2 man crews. But regulations can change as technology gets better, I honestly believe railroads will automate. Not the entire system but I can see it being done to a point where mainline trains run crewless to certain points then have a crew take over for more complex sections or operations.

[@Hyce777]

I will not be surprised if that's what happens some day.

[@cliff4377]

There was a example of why ptc is necessary on some new track in the PNW a few years ago, it's always a stupid story.

[@Hyce777]

Yeaaaah I used to work there. Lol

[@BeckaReus]

A bit that you didn’t cover: When running without PTC on track that requires PTC your speed is limited to 49 mph. I believe but will have to look up the rule [we do it so rarely] that key trains are even more restricted.

[@ELDRGW]

A good example of what ptc can't stop is the up iron ore train that set the land speed recored for north American freight trains at 155 mph before it hit the ground in Kelso.. Can't stop a train without breaks and a crew..

[@Hyce777]

Well when you let it roll away without air.... No one can stop it. Lol

[@Dan_Gyros]

That system is really cool honestly, and I can definitely understand the drivers worry about losing jobs, but I honestly don't think the public would allow trains to drive autonomously when its not like an airport shuttle or something.

[@douglasengle2704]

I got a lot out of this. Speaking from an EE software standpoint Positive Train Control is in concept fundamentally different form past safety systems in that it has to give authorization for a train to move and keep moving verses a safety system that gives a warning or takes action when a fault is discovered. Discussing how the train has to be "initialized" with Positive Train Control was helpful in understanding the running of the system. With only radio GPS for location a train couldn't initialize in a tunnel or poor radio reception area. The work around for using dead reconning after initializing from a known location was interesting, but how do you move the train from not being able to initialize to a location it can? That off system PTC movement would have to place outside of the Positive Train Control systems operating model. For many previous decades when positive train control was discussed knowing the exact whereabouts of a train would require frequent track sensors and means to identify the particular train with that sensor. That is used in DC's Metro. Highly reliable radio satellite GPS has allowed much finer locating than might have been expected, but it is still radio subject to interference and doesn't work underground or in radio dead areas. It would seem that in such areas track sensors would be used. Having to be wired together and supplied power makes track train sensors are a significant electric data and power distribution system of its own. In a tunnel or trench situation that would seem acceptable. The fundamental operational problem with positive train control is everything has to work or have fail in redundancy to do the anything. It doesn't improve train movement efficiency. It would be key element in any responsible no onboard crewed train automated operation. Long haul freight trains requiring crews to overnight away from home has never seemed a good home life. Future PTC with automation was expected to allow long haul freight trains with nobody on board with a remote operating engineer and the trains being received by local persons in train yards. That wouldn't have a person on train to be there when an incident takes place. Video camera transmission would be hard to guarantee continuously that would proved the remote engineer with the train few. Except for special situation with good radio and few road crossing it still doesn't seem viable. The FRA requirement for two man crewed train operation to a rail fan doesn't seem like it should cost much to major freight railroads with all the other expenses of running a railroad. Incident handling with no crew or single person train crews would be more expensive per incident than if having two person crews. Looking to the next generation of train engineers having long haul freight trains run by an engineer in a remote office would mean no overnighting away from home and more regular working hours. Incident handling would be more difficult with nobody on board Any train stopping failure requiring getting access to a stranded train. It would seem regular no-crew-on-board operation would need a parallel track access path for utility vehicles to make this viable. A high railer could access to a stranded train by getting track access at a road crossing then get to one end of the stranded train. Then a train conductor would have to walk the ballast to find the issue which an on board conductor would have done immediately. This would take huge amounts over what would take place with simple incidents when having an onboard conductor.

[@Hyce777]

Yeah it's challenging these days if you fail to initialize due to a poor reception area. At this point they're pretty well known and there's response plans for how to deal with it, ideally starting from somewhere else. Mostly affected commuter roads with starts and stops in big urban areas on the main.

[@ShuRugal]

@6:30 - "lots of switches" dumb network engineer thought: what if you used the rails to carry a CANBUS network? then you could have a vendor agnostic setup where any PTC-compliant monitoring device just tell "the rail" what its status is, and any PTC compliant locomotive could read "the rail" and learn status of track devices and get hazard warnings.

[@railwayjade]

Hyce does PTC measure distance in miles/feet or in meters? Example, our ATP used to measure in meters, even with the UK ECTS, though they use mph, the system measures in meters as far as I am aware. We use the measuring feature when the train dives underground and it becomes time to announce the station as one function. I used to think ATP is not such a cool thing but then I rethought about my position and that no one complains about pilots getting extra safety features, we as train crews deserve the extra help too. Safety is a good thing.

[@rambling_railfan]

23:26 *Cough* Strasburg 475 *Cough Cough*

[@wmoscati]

PTC could have prevented this video... 😁🙃 Great vid dude, thank you

[@Djjordeyg]

Boys, finally we got it