I know it's obvious, but I should say it anyway: the public can't get close to these signals. Do NOT go onto tracks without permission. Access and overflight requires a lot of co-operation and paperwork, and I'm extremely grateful to all the Network Rail team who helped with this video!
“As small as a microwave […] as large as a washing machine”: I love the idea that this guy only ever uses the relative sizes of kitchen appliances as a unit of measure.
The Epitome of "If it ain't broke, Don't fix it" There's actually a lot of old technology that thrives that runs minor and crucial systems around the world. Brilliant pieces of engineering that you can only marvel at. From there are inventions that are merely advancements of one person's design. It's one of the best things about the human brain to Tinker.
Very impressed by Alastair's knowledge of the systems involved and eloquence when explaining the various aspects of each. It's nice to hear an expert talk about a subject they're passionate about and it's one of the main reasons I enjoy Tom's videos so much. Cheers @Tom!
The crew behind Anderson's piano probably had no idea that their system would last longer than the era of steam locomotion, let alone into the 21st century
@@Eustathe Electric engines and diesel engines were known about at the time. It was a problem of efficiency not discovery. Anyone that was well read would have known that these concepts were likely the future, just a matter of when.
I work for a Software company that creates a lot of technology for ensuring the Rail Network in the UK is safe (such as gauging). I have absolutely no idea how I'd approach this issue, and honestly, I think wire on a stick is still the best approach. Well played, Scotland.
Lots of others have replied with the same idea I had: a sensor on the danger-signals, that when the mechanism trips, also triggers the sensor which then sends a packet to the central control. They clearly have the system for the _much_ more prolific tilt sensors already, so could derive from that. Some ppl ask about power, but a small solar would obviously be enough (it would literally off by default, as the danger-semaphore would act as a switch closing a circuit) with a small battery, despite it being scotland. And one even brought up how the mechanism could provide enough energy by simply releasing a weight powering a gravity-clock-esque system, or outright use the mechanism itself as such, to generate the little power needed. Which honestly is kind of genius in how cheap that would be compared to sourcing a tiny solar panel, or even the small flat batteries used in wristwatches.
@@feha92 just glue a magnet on the signal and put a coil beneath. No need for fancy power generation. The drop will generate the current wich could be registered by any microprocessor just let the pin be an interupt
A survey drone is my best guess (Lidar on a UAV) which flies the track ahead of a train. That results in a point cloud of heights which can be very accurately geo-located, and that then turns the rock problem into a relatively simple bounds check in software. Even a £5k commercial drone is likely a lot cheaper than maintaining their current setup. Or an even simpler one: just stream the video from a drone to the human driver of the train.
I've travelled on this line many times and I had no idea there was anything like this going on behind the scenes. I've a new found respect for Scotland's railway men and women.
I wonder why they haven't written a manual on the maintenance of this system? Sure, a lot of it is probably fiddling with it (in an engineer way) until things work properly, but there should be no barrier to writing out what the general methods are, and the "DO NOT DO THIS UNLESS YOU WISH DEATH" warnings.
Exactly what I was thinking. Obviously its a complex, manual system, but tons of far more complex systems have written manuals and videos and the like to give information on said complexities. Seems strange to have this information be "passed down" from year to year as if it would be impossible to create a guidebook that supplements physical interaction with the device. Would be like a 50s car just having absolutely no written documentation on it, simply because theres two guys around that know how to work on it and they'll explain it to you if you ask.
There likely are a few maintenance manuals for it, written a century ago, but the parts that they used in there are, for the most part, either long obsolete, or were all "house made" by the local steam train service shop, using the blacksmiths and boilermakers there to manufacture them all in house, along with railways carpenters that made the wooden aspects of the system. Kind of hard to replicate without a large forge, power hammer and a lot of skilled craftspeople to do the various aspects. You are not going to buy the parts off eBay for this easily, and most hardware stores will look on you in puzzlement when you ask for a sixpenny nail or a tuppence one.
I suspect that that was a bit of hyperbole. They probably have written a manual. And yet, as a carefully balanced mechanical process involving carefully balanced tensions, counterweights, friction, etc. there's probably a reasonable element that you can't learn just from reading a book. I expect that you also need some hands on practice with the system to learn the practical skills to turn written theory into practical results.
I'm sure they have, but it's obviously not been written by whoever designed/built it originally, which is how modern systems are documented. It means you can still get unforseen and undocumented problems which need a fundamental understanding of the system to solve.
The fact that Tom consistently, week on week provides an extremely interesting video about a subject I would have never thought about before is magnificent. Thank you Tom for all that you do!
From Edinburgh head north, take the A9 past Perth, hang a left at Dalwhinnie towards Fort William. It's about 3-4 hours and takes you into the scenery you're going for, if you ever decide to come :)
Visit Scotland! You'll love the different landscapes. Expect vast areas of green and also areas of nothing interesting, so to speak. When I went to the Highlands, I was told to expect not that much but I enjoyed the day tour going to water falls, glens, dams, castles, etc. Scotland is really a rather amazing place to visit. Don't forget to try the food - I can't find good haggis anywhere else!
It's actually a bit funny to imagine someone from the rail service ordering new wire for Anderson's Piano starting with the line, "I need 100 metres of your weakest wire"
Simple enough, you take a few dozen samples of the original wire, and send them off for tensile strength testing. Then you get a nice set of figures for the tensile strength, and the elongation at yield, plus a plastic deformation load. then your request for supply goes out to your suppliers for a wire, coated with zinc, like most wire is, that is within 10% of these 3 parameters, and you get the result back. Choose a supplier and order 100km of the wire, test on arrival to ensure it complies, and place a few rolls in the local stores area, ready for use there. Not at all difficult, and while the new wire might be a little thinner than the original steel, due to improved steel making resulting in a higher strength steel, it will still fit the old mountings and apparatus perfectly.
I'm a train operator in the US. I can completely understand how this system would still be the best. Sometimes it's an old solution or principle that is the most reliable in terms of energy requirements or practicality. Also, I can definitely vouch for the dangers of larger objects. It takes a lot to derail a train but sometimes, all it takes is a cow or a deer. I've seen it both ways.
@@blazerorb not all objects get pushed out of the way. Most locomotives have some sort of plow, but they are different from the cliche cattle-catchers of old locomotives
@@SupernovaSpence this is fascinating altogether, but I'm wondering exactly what you mean by "not all objects": are you referring to just particularly large and heavy things, like Alastair the engineer's example of a washing machine, or can smaller stuff like, again, microwave oven-sized rocks also 'bypass' a big, front-mounted plow?
@@SupernovaSpence unless your in a canadian winter . A freight train with a snow plough is a site to behold in heavy snow. And if there is a snow bank you back up so you don't get blasted off your feet from the oncoming snow eave
@@mnxs I guess, depending on size, weight and where in relation to center of mass of the object, it could go to either side, or under the plow. The plow probably can't scrape neiter the rails nor between them to push everything away, for the same reasons our toy cars got stuck when transitioning from the back rest of the sofa to the sitty bit. Trains also have some "slightly" more gradual transitions like that :)
I just think that this proves that trains and train related devices are already near-perfect. I mean whenever someone tries to reinvent transportation, it just ends up coming back to trains one way or another. What I'm saying is that trains are perfect and awesome machines.
There are so many critical systems built today that aren't built to last 10 or 20 years, much less 100+ years. I hope the lessons and work of engineers and construction workers from back then survive our modern 'build it as fast and cheap as possible' mindset and thrive with a new generation. That said, the mindset and detail-oriented designs of past decades, applied to the technology we have today, could result in systems that are as robust and resilient, while also cheaper to maintain. We just need to back off a little bit from the "always choose the lowest bidder" option.
I think the main trouble is that parts are outsourced or designed by specialist companies. Those companies have it built into their business model that they want/need the ability to sell replacements/upgrades to the same people in years to come.. so it's in their interest to manufacture parts with a lower shelf life. Very hard to police that. Somebody who worked at a power tool company said that they literally *could* make a motor that would last 50 years, but the design it to only last a fraction of that.
@@Krytern well so I was going to say the expression seems a bit misplaced here and I also can't stand the use of cliché expressions when they're not thought of, just use them cause they're common sayings or expressions... Cause it makes no sense in this case it's more like; if it breaks it means it's working... Allthough it does make some sense in the way of saying; if the system that way itself ain't broken, no need to replace it cause it works well... But even then "if it ain't broken don't fix it"? Nah, it functions the other way around; if it breaks don't fix it cause it means there's probably rocks on the tracks... So uhm yes I get it. Pardon me Rich G, I understand what you mean to say but I disagree with saying it's the ABSOLUTE definition... It's VERY relative in this case I'd say. 😉
I work in an underground mine in canada, and we use the same type of "tensioned rope with a flag at each end" system to monitor the beltways that run underground. It works, and it makes it easy to find a problem. You just drive until you find a flag up.
I like the size comparison to microwaves and washing machines, rather sensible. And the timing of the Sprinter at the end there was impeccable! Also was quite surprised Geoff didn't make an appearance here :P Interesting bit of kit too, think I've heard of it before but never really looked into it.
I thought size of a microwave as in the wavelength of frequencies in the 'microwave' range until i noticed hes talking about an actual microwave oven 😅
There is a similar tripwire system used at the eastern end of Southend Airport to protect against an aircraft running off the end of the runway and onto the railway. If it's tripped, the approach signals on both roads are dropped back to red and it requires a physical re-set afterwards. (Presumably Instruction No.1 of the local procedure reads something like "Check for bits of burning aircraft on the railway".)
Exactly the same problem exists for conveyor systems - pull wire switch monitors exist to tell operators exactly which switch is tripped on 20 km conveyor systems with a switch every 100m. On conveyor systems they still need local resets because they are a safety of life system but simply knowing which of the 400 switches (they are on both sides) has tripped is a massive time saving. The radio transponders use lithium batteries that are changed every five years.
Very well done. It’s a real treat being able to view parts of Scotland’s railway system. American railways are built on the foundation of what was created in your land so long ago. Love the semaphore signals! I’ve visited Glasgow and Edinburg, but I would love to see the whole country; especially all that lies to the north of G & E. What a lovely country!
I love how the guy went "We don't need them to be stronger; we need them to break." Sometimes, improving on something has a negative effect on the current needs huh?
That happens when you buy something that has not been made to the specification you need, but just has them by chance. IIRC, there was something similar with Mercedes. Unlike their competitors, they were still creating the turning signal noise only through the clicking of the relays while others were using dedicated tiny speakers. Worked well until the relays were changed in some way and did not have the familiar clicking sound anymore (because most manufacturers do not have consistency of clicking in mind when optimising durability etc)
I know about similar situation in NASA, when they had used shuttles, they were purchasing emergency ladders, and, at some point manufacturer decided "let's improve our materials" and changed fabric to more strong one, wich is also more slippery for space suit. Astronauts didn't know about this during training, so one of them even gained trauma because of fast descend and following collision
During Christmas 2016 I got stuck for an extra overnight at Kyle of Lochalsh (that's on the northwest mainland looking over to Skye) due to a landslip disrupting the tracks. The wires broke, word got out and my train was cancelled. Spent it in a cabin looking out to a ruined castle during a storm, with a log fire going and history books to read by the window. The system works. PS There was a battle at the Pass of Brander / Cruachan area in 1308 where Robert Bruce and James Douglas ambushed the Macdougalls by climbing over Ben Cruachan. The more you know!
it could still be improved , it could send a bottle of the local Talisker whiskey to your cabin and have you boss phone you to say you can take another week off and have a pay rise while your at it.
This system isn’t used on the Kyle line. That part of the word it was likely a roach fall incident, we have them fairly frequently despite nearly annual work installing mesh over the cutting faces
As a happy passenger who's been lucky enough to travel by train through the Highlands, I'm grateful for this technology! And I highly recommend this trip to everyone, it's spectacular! 🚂❤️
I find it amazing how many big institutions rely on "tribal knoledge" passed down previous employees to newer ones. The inability to store and access legacy information on processes and equipment is a major problem that needs to be addressed of we are to operate in a world of very long life systems.
OTOH, it provides some employment security. People can't be replaced without being able to pass knowledge down. You might be surprised how entrenched this thinking is, and it's not without some justification. Before presenting "solutions" from on high, you have to reassure employees that it won't make them redundant. Especially if you're actually trying to make employees redundant.
@@squirlmy OK, but what happens if the person with the specialized knowledge dies in a sudden accident? There's no harm in having it written down or otherwise codified so that the knowledge is not lost.
@@chrysshart I would say for this specific application it's a team of people so the likelyhood of them all dying in a freak accident is slim. Most modern businesses that use general labor have a written S.O.P for the task, but I would consider this a niche case.
@@chrysshart You are right, there is no decent reason why this system couldn't be documented to a reasonable level, of course anyone working on it is always going to need a fair bit of common sense but its not hard to write down a decent crash course in its operation and maintenance.
I love this mix of the old and new technology he's talking about, the balance of what works and what's innovative and potentially more capable, with an eye to geography, weather, and what's possible. That's the right mindset.
Railroader for eight years here. I worked in Montana for a while and we had these for a section of our track which was adjacent to a rock face. I have personally only seen this system set off once before which was for a fairly large rock that got through, but wasn't on the actual track. There's also a permanent slow order through that zone which was 30 mph. If it works, no need to fix it. The fact is that many of the technologies used on trains and track is decades old, some of it over a century old now.
This concept is widely used in the US, except it's generally based on on an electrical current passed through the wires, and any break is detected and alerts the Dispatch directly. It is mechanically much simpler, just wires stretched on insulators, but this is unique in that it does the job with no power required. If it were me, I would put a small telematics box at each signal that sends an alert anytime it is tripped. If the cell network is available, they can last 5 years on a lithium battery because they don't actually use power until they are tripped. If you only had satellite available, a solar panel and battery pack could keep it going the majority of the year at least, and you add this to the mechanical signal so even in the dead of winter if the solar system dies the train still gets a warning. But having the remote alert would allow track workers to respond as soon as it happens, rather than only after a train reports it. On the other hand, maybe there is a train through there every half hour, and adding a remote alert would not gain anything!
unfortunately, setting up such a system would be a large investment, one which perhaps the government, or even specifically the rail administrators, won't see as worthwhile, certainly not in the short-run, not while they can make do with the current system. Unfortunately politics, inter-administrative, national and local, plays a huge role in these matters. On the other hand "don't fix what's not broke" also has a certain wisdom to it. This particular system has worked 140 years, can we be reasonably sure cell network or satellite systems won't have unforeseen issues that negate the benefits?
For an electrical system Wire would be 5-6 grand, electronics would be a grand per box, times 4 (for redundancy), so 10 grand The advantage is that you can just solder the wires back to reset. Though another option would be to keep the existing system and just add a monitoring device that checks the state of the flags and reports it immediately.
Very poor radio reception for aught above MW up that way. It's not that far from glencoe... Which can't get terrestrial tv signal. Back before Iplayer etc TV licencing repeatidly took residents who had sky dishes to uk court, despite EU courts each time overruling saying that as no terrestrial service... Tv licencing was (fraudulently) attempting to charge for a service they simply didn't provide at that location.
@@satibel the cost to run copper wires then you have maintenance cost old system vs new system. for this salutation it honestly makes more sense for the train driver to go slow during a warning
I love the environmental side of this. You're trying to upgrade a system, and you're not allowed to use (much) power. Having that reminder that not everything needs to have a million sensors and a self-learning algorithm is kinda nice.
There would likely be a net environmental benefit of installing a power hungry protection system becausse it would make the railway more reliable, displacing cars
@@sublivion5024 Seems like that'd depend on a bunch of factors. A railway monitoring system would use, give or take, the same amount of energy per mile as any other mile, but a more remote section of track would be relevant for fewer people who aren't already using it, and at a certain point, running a system 24 hours a day, 365 days a year is going to be a bigger drain than is offset by X extra loads per year of people and cargo. Remember that it is being used by some already, and the system seems like it works, for the most part, so the reliability can't be too great an issue.
Love Victorian era railway engineering, the ingenuity applied to problem solving without electrical and electronic systems is amazing. Having said that, as an old hand Signalman it came as a bit of a shock to see non absolute semaphore signals with red arms
@@oscarosullivan4513 was and still is tho I do miss the exercise these days. Sitting in front of a bank of monitors doesn't have the "feel" of 192 shiny steel levers and panoramic windows
I adore analog engineering Digitals great and I wouldn't want it to disappear. But it's not as satisfying as analog and you feel like making it is more of a challenge
"Something as small as a microwave can cause a train problem, something as big as a washing machine could lead to derailment..." I guess they have problems with domestic appliances tumbling down mountains in Scotland!
A few years ago some volunteers cleared a lot of the human debris left at the summit of Ben Nevis, Britain's highest point, and well visited. Among the items they had to deal with was a piano, thought to have been carried up there as a prank by some students ! Throwing it over the north face was not an option ! (No, it wasn't Anderson's piano !)
@@tonydarcy1606 Easy solution for the piano. build a trebuchet at the summit, fling the piano off the mountain (and PLEASE record the sound, for comedy). What's that? Now there's a trebuchet on top of the mountain? Bah, details.
For those wondering why the double-semaphore has one painted red and white. A signal is painted red on one side, or yellow if it's a distant signal (iirc), and white on the other. Train drivers facing the red or yellow side must obey the signal's position, but facing the white side the position is ignored.
@@robinbennett5994 It does, that's why there are two signals. One for each direction. The line uses a Single Line Token Block system to ensure two trains aren't occupying the same track in opposite directions.
Wow that's amazing, I have hopped almost every mainline in America. I would love to hop through there it looks gorgeous. I love old analog tech, especially in the train sector.
Sometimes an old solution is still a good solution, or at least "good enough for now." I'm willing to bet whatever technology eventually solves for this problem doesn't last 140+ years like this has.
Indeed. It's also less susceptible to becoming obsolete. I mean, there are some pieces of industrial equipment I've seen that still need Windows 3.1. Meanwhile, something purely analogue like this doesn't need to worry about that sort of thing.
If whatever tech replaces it doesn't last 140 years, that would probably be because technology advances faster now, and will probably advance faster yet in the next 140 years.
"small rocks can be an issue for trains" "huh never thought you'd be able to stop a train with a pebble" "rocks as small as a microwave oven can be problematic, washing machines sized obstacles could cause derailment" oh
On the North American rail network, the lines carry an electric current. When a rockslide, snowslide, or other avalanche breaks the circuit, it triggers a red signal on the track and alerts the control center (which is often thousands of miles away).
This is for stretches of rail where power sources are not available or not economical. As one US train driver commented, they use a system like this in remote areas in the US.
In the UK, electrical signaling goes everywhere the trains do, so not a problem, however a mechanical switch at each wire could be tuned to alert central control if the wire is broken or pulled, with different alerts per direction . If something is leaning on a wire (pulled), an investigation train can be sent to identify and remove it . If something bigger breaks a wire, investigation train also needs to install a new wire and reset the tension to return the sensor switch to middle position . One advantage of such a basic upgrade is to signal trains to slow down before reaching the alarm area, with all the modern procedures of other temporary speed restriction signals .
Sehr altes und nicht gerade überzeugendes System. Gehen sie zur SBB (Schweizerische Bundesbahn) und schauen sie, wie diese hochmoderne automatische Technik funktioniert.
But if the current is in the rails, wouldn't this only work if a rail is actually broken??? And if so, might it not miss a rock or a pile of snow which obstructs the tracks but fails to actually knock a rail out of place???
"something as small as a microwave could cause problems to a train" for a moment there i was mesmerized about how a wavelength could cause problems to a train
"There's not a user manual or a downloadable book on how to maintain Anderson's Piano. We need to pass that down through generations of technicians and engineers." Have those technicians and engineers considered making a user manual or downloadable book to make that process easier? :P
When I saw the thumbnail, I thought you were talking about semaphores. :) I was confused because there are regular lighted signals on certain railway lines these days, not just semaphores. The mechanical rock fall detection system makes more sense (and makes a lot of sense for needing to use semaphores :) ).
@@markylon That would be "regularly lit" as in frequently, or with a constant time interval. "Regular lighted" might have needed a comma ("regular, lighted"), as they're both descriptors of the signal style, and indication that "all" signals contain nighttime illumination of some form or other, these days.
Fascinating as always. When I saw that last train coming by I thought "Wow, Tom really did a great job of setting up and timing that final shot!" Little did I know . . .
@@fetchstixRHD I've watched a piece about "Anderson's Piano" somewhere before and ironically I think it was on an episode of Scotland's Scenic Railways that also featured Geoff and Vicki travelling to Corrour.
I consider this one of the best short descriptions of a technical device on UA-cam. Thanks to a cleverly setup of introduction, questions and moderation, it is the thoroughly thought-through text spoken in on and off of the railway engineer that does one make interested in railway design way beyond the pure coveredge of the 'Anderson's Piano'. So, thank you for it from Austria. /wp
San Francisco uses the same (incredibly clever and robust) system. Unfortunately they seem to be having some trouble with maintenance due to the age of the system. There was a news story a few years ago that they ran out of "out of order" notices and had to resort to duct taping red bath towels over non-working pull boxes.
Given the amount of avalanche and rockslide detection systems here in North America I’m surprised none have fitted the needs in Scotland. Also, the continuing past a “danger” signal exists here in Canada; there are two in fact: “restricting signal” and “stop and proceed signal”. Essentially, you continue at a speed below 15mph at which you are able to stop at half the view range distance (ex. You can only see 500 meters ahead so you must go at a speed in which you can stop in 250 meters). These are usually in automated CTC (central traffic control) portions of track that operate by the axels of trains completing a faint electrical circuit in the rails to trip signals and usually give this indication if there is a grounding of current or a cracked rail.
Given the average speed of tracks in the US and its infrastructure grade of D- I wouldn't be surprised all these brillant systems imediately went into the bin
A similar thing exists in Hungary for block signals, since they're generally out on the open track where station personnel isn't available to check that the train can pass safely despite the signal showing "stop" (danger). In general, the engineer has to wait for two minutes before proceeding at no more than 15 km/h, but the wait isn't required if on-board signaling is available and if the on-board signal shows clear beyond the signal, they engineer can speed up. (I'm glossing over nuances here for the sake of brevity)
I'm quite sure that Tom Scott was a bit mistaken on the 'always stop on red'. Google "permissive signals". Those exist in many countries, including countries with a quite modern rail network such as The Netherlands.
In the UK are signalling system is not speed based signalling but route based signalling. The line is signalled under RETB=Radio Electronic Token Block. You simply add a Semaphore calling on Indercators in the form of a mini Semaphore signal.
Ironically the issue of not having power in remote areas also plagues the power grid. If you're trying to set up a SCADA system in the middle of nowhere to measure current flow it's going to cost $10,000 just for the transformer that gives you access to 120V/240V power for your computer systems. That's the best case scenario for an issue that by definition is under an existing power line.
Wouldn't solar power be a good idea? Where I live there are ton of flood gages. They are all solar powered and talk to Flood Control over the cell phone network. There's even a website where regular folks can check levels.
Probably still cheaper than running another cable with 240V! I imagine solar cost/efficiency + battery + ever reducing watts/hz in computing gets you over the bar with sufficient reliability margin in a growing number of cases as time goes by. There’s plenty more instrumentation manufacturers could be doing to reduce power consumption and reliance on a town power supply. None of that equipment -needs- to run on a 240V supply. Open it up and you’ll find a Switched mode supply giving you 12V and 3V3 DC rails.
I love how Tom keeps finding interesting things in the UK to talk about. It makes me want to visit the UK to find out what interesting things I can find.
That was great timing with the Class 66 at the station and later the ScotRail Class 156. I'm always pleasantly surprised when Tom uploads a railway video.
I’ve lived near there for almost 20 years, and I never knew about any of this! (Only thing that comes to mind for that railway with me is the derailment that happened in about 2010)
This kind of videos, very informative and interesting, is my favourite thing to watch. I really enjoy learning about various things you show and from interviews with people working there. And your thought add a lot. Thank you, Tom, for making it.
Permissive signals, where after they're at danger you're allowed to proceed anyway just slowly and within sighting distance, are very common worldwide. France and the Netherlands are full of them. Britain is actually quite unusual in not using them anywhere.
Nope, Britain has permissive signals in a lot of places too. Usually they're used for things like allowing a train into an occupied platform block section in situations where it is supposed to couple to the train already there.
I was under the impression that if the shunt signal beneath (if there is one) shows a "proceed" aspect, trains may continue at shunting speed even if the main signal is at danger. As other have said, they're mostly found near station platforms and railyards.
As always, impeccably timed and narrated. Reminds me of the other rock detection system in place, you covered last year (?), with the traffic lights on the road, albeit, this is longer and more complex in needs!
Having passively active systems that don't require power is just great. I whish more solutions with less or "other" power would be used. Electricity and computers have become the common standard, but aren't necessarily the best option. Thanks for this intriguing video. :)
Dear Tom Scott I am from Bangladesh,my father was Bangladesh Railway worked as SIGNAL ENGINEERING so called inter locking system and wireless system,so far I loved RAILWAY,your presentation is realistic,thank you,wish your stable health plus waiting for the next presentation.
This failsafe system kind of reminds me of the one in industrial looms. A piece of metal shaped like an upside down U is put on every thread of warp (that's thousands of them) and should one break, the piece of metal falls on a special surface underneath closing a circuit. The stop is automatic, though, unlike in this video's case - it makes the loom halt and shows an error. Unlike the trains, if an industrial loom continues weaving, even slowly, after a string of warp tore, it's a problem.
Similar: High end kitchen mixers have a critical gear that's made of plastic. It's designed to break before more important (and more expensive) parts of the engine break if you over-work it.
@@ItsMrBozToYou and now they have table saws that fire a charge to stop the blade nearly instantly, when there's something conductive touches the blade. There's a video on UA-cam that was done with high frame rate cameras, and using franks in place of someone's finger. The stopping power is so effective, that it tore apart the teeth not in contact with the brake on dado blades. It works much like air bags in a vehicle, but slams the blade rather than inflates a bag.
But those things also always remind me of humans and tchernobyl: we dont know totally whats going on but lets ignore warning signs, surely everything is alright and they can be ignored, the warning just is wrong.
A very nice video, thank you. It's about the same over here, for slide/fall detection. Very much more integrated with the signal system and dispatcher, but a fence is a fence at the guts of the system! I worked with the railroad for 39 years and I will say that "If it ain't broke, don't fix it" is a viable option in considering system changes or upgrades. Every system/option has its trades.
Reminds me of how the lights for the railway crossings here still use mercury switches, even though they've been banned for almost everything else, because they are just so much more reliable then any other electronic system.
In Germany we use the same system still today. It's called "BALA": BoschüngsALarmAnlage". Word by word translated something like "embankment alarm system". We use it not only for rocks but also as detector for levee slides after massive rainfalls. The only electric thing in the BALA ist a simple box in the office of the signal dispatcher which screams loud as hell, when the steelwires on the hills lose their tension.
Tom, again a great video! You really have a gift to find these stories and the people who are so invested in their jobs - the Scottish engineer in this video or the Germans from Deutsche Bahn from the training center for signal workers (?)!
That the "Anderson's Piano"-system operates to this day has something to do with a railway safety principle. That principle is simple: a railway track wich is free from trains gives a continuous electrical signal to the main safety system saying: I’m free, trains are welcome. When a train is on the track, it shortcut this signal and the main safety system puts the signal that gives access to the track on Stop. This safety principle has also the effect that when there is a malfunction, the main safety system always keep a signal on Stop. It’s also known as "failsafe". The Anderson's Piano-system is based on that same failsafe principle, but instead of a continuous electrical signal, it uses a mechanical continuous signal in the form of a wire. If a wire malfunction, the connected signal falls down to Stop. Replacing this system gives two main challenges: making a system that is failsafe and making that the system gives less false reports than correct reports.
The modern world is starting to use axle counters instead of electrical track circuits. They are not prone to electrical leaks and other insulation problems. Same number of axles in and same number out -> track is clear again. There is drawbacks though. Axle counters can't detect broken rails, but with modern rails that's not too big of an issue anymore.
@@laju axle counters also lead to fun situations where trains are not allowed to have particular numbers of axles. IIRC there's at least one place where trains are not allowed to have a number that is 0 (or possibly 1, I'm blanking on the exact details) mod 256 because they only use a single byte for counting and they don't check for overflow 🤦♂️
This is even a safety feature for rail crews. When I worked on the railway, they issued 2 metal clips connected by a wire (essentialy oversized jumpleads) as part of safety kit on every train and in every van. As part of safety training we were taught if there was ever an emergency on the line which required the stopping of trains to prevent further incident, use these clips to connect the 2 rails together. This will immediately set all signals to red and so stop any other trains proceeding into your area. Of course this works both ways. You also have the vandals who know about this and purposely put a metal bar across the rails just to cause havoc!
They still use something similar in the US along certain routes. I rode Amtrak from Omaha, NE to Oakland, CA in the 90's and along the mountain passes from Denver to Sacramento there were multiple wires stretched along beside the tracks. At that point I had no clue what it was but learned later on that they were there to detect rock falls and such. It's an amazing trip going through the mountains for sure though. I went through in December headed west and January headed east through those area's, something I truly want to do again sometime.
Funny enough, Just last week I finished my Canadian railway signalling course. Over here, there’s actually a few signals that abide by the same rules! If they’re set to the most restrictive aspect, you must proceed at a speed that allows you to stop within half the range of vision of equipment, not exceeding 15 MPH. (I know, we should be using metric) and be on the lookout for broken rails/track washout. Neat to see that that rule is somewhat implemented across the pond!
@@Inkyminkyzizwoz Fahrenheit is superior in the US as there is an entire body of knowledge referenced in US units. All just available from countless standards and tables.
I was wondering about Canada, having driven along the highway through the Canadian Shield in Ontario and I'm sure rocks have been a problem for trains over the years.
It’s amazing how much upstate New York and Scotland look alike. The rivers cutting through mountains on both side and the utter bleakness in winter. Fantastic.
One alternative, which is currently used for some infrastructure in the UK, is a fibre optic sensing system. Essentially very similar to this, except instead of cables there's fibre optic wires. It'll generally detect an issue before the rockfall happens, because the wire will measure increases in strain at every single location on the wire at high resolution, and can pinpoint exactly where the issue is.
Fascinating, especially also what methods they use to keep rocks from falling, or in other instances, to at least catch them before they reach the rails!
Anderson's Piano... Definitely never heard of it, but it's simplistic and brilliant. I went on to research this more on YT and this was the only video about it. Well done!
I wonder if they set the tension for c1 or g1, with a precision fork, but may be h is b in your system, that's a mess, and the question is baroque or modern intonation, so do re mi fa g-enius! For windspeed, they use chimes ...
It's interesting-there are places on the Pacific Coast Highway in California where they use the same kind of restraints to keep the cliffs from sliding down onto the road. And since for a lot of places on the central coast, that's the only road into and out of town so if that's closed, there are huge detours to try and get to the town from the other direction.
Got to admit it's a bit weird hearing recent videos describe places in Scotland like Oban and Helensburgh as being in the south west, and Fife in the south east. I mean technically they are south of the geographic centre - but no one from Scotland would say "in the south west/east" for these places!
I know it's obvious, but I should say it anyway: the public can't get close to these signals. Do NOT go onto tracks without permission. Access and overflight requires a lot of co-operation and paperwork, and I'm extremely grateful to all the Network Rail team who helped with this video!
Yes, unfortunately there are those among us who lack the necessary common sense. It sadly does need to be said
the fact that this had to be said just shows how people will go to great lengths in doing something stupid
why can't they cover it? I know they've covered parts of rail in British Columbia due to potential landslides.
@@Noah-lj2sg No
@@Noah-lj2sg bro i see you everywhere
“As small as a microwave […] as large as a washing machine”: I love the idea that this guy only ever uses the relative sizes of kitchen appliances as a unit of measure.
Imperial be like
How else would American viewers understand???
Next up: Small boulders of the size of large boulders.
You’ve got a washing machine in your kitchen?
@@ziiofswe i mean these mfs already measure mass in stones
@@zeussierraalex who tf has washing machine in their kitchen?
The Epitome of "If it ain't broke, Don't fix it" There's actually a lot of old technology that thrives that runs minor and crucial systems around the world. Brilliant pieces of engineering that you can only marvel at. From there are inventions that are merely advancements of one person's design. It's one of the best things about the human brain to Tinker.
I really love seeing this old technology that is still used in major way.
I wouldn't call it an epitome of that because the engineer says it's a clumsy system and they would replace it if they could.
ironically, these wires are meant to break, and then have to be fixed when they do
the problem is, the system breaks all the time... its made to do that
@@katiehazeltine5312 I should mention that when I say if it's not broke... I'm talking about it's over all reliability. Not that it actually breaks.
I honestly could hear this guy talk about trains and rail for days.
Tom or the Scot? I could listen to both
@@turtlegamez4274 definitely both
That Scot has the perfect combination of a nice Scottish burr with clearly spoken English
very ASMRish indeed
yes, it is so soothing
This system was originally designed to keep Glasgow residents out of Edinburgh, but it was far more effective for rocks and trains
The only thing keeping Glaswegians out of Edinburgh is pride.
@@shortymcsteve and the stench
@@alanmc1846 And the price of pints
@@salientsolution5436 and the accent 😂
@@shortymcsteve and the tourists
Very impressed by Alastair's knowledge of the systems involved and eloquence when explaining the various aspects of each. It's nice to hear an expert talk about a subject they're passionate about and it's one of the main reasons I enjoy Tom's videos so much. Cheers @Tom!
trains one way or another. What I'm saying is that trains are perfect and awesome machines.
The crew behind Anderson's piano probably had no idea that their system would last longer than the era of steam locomotion, let alone into the 21st century
They probably had no idea that the era of steam locomotion would not least forever...
@@Eustathe Electric engines and diesel engines were known about at the time. It was a problem of efficiency not discovery. Anyone that was well read would have known that these concepts were likely the future, just a matter of when.
@@Eustathe People back then were not idiots.
@@MentalParadox nee, echt waar? 🙄
It's really amazing to think that something so small and simple can be developed into something huge and complicated and/or last decades or centuries
I work for a Software company that creates a lot of technology for ensuring the Rail Network in the UK is safe (such as gauging). I have absolutely no idea how I'd approach this issue, and honestly, I think wire on a stick is still the best approach. Well played, Scotland.
depends what they are prepared to pay
Lots of others have replied with the same idea I had: a sensor on the danger-signals, that when the mechanism trips, also triggers the sensor which then sends a packet to the central control. They clearly have the system for the _much_ more prolific tilt sensors already, so could derive from that. Some ppl ask about power, but a small solar would obviously be enough (it would literally off by default, as the danger-semaphore would act as a switch closing a circuit) with a small battery, despite it being scotland. And one even brought up how the mechanism could provide enough energy by simply releasing a weight powering a gravity-clock-esque system, or outright use the mechanism itself as such, to generate the little power needed. Which honestly is kind of genius in how cheap that would be compared to sourcing a tiny solar panel, or even the small flat batteries used in wristwatches.
@@feha92 just glue a magnet on the signal and put a coil beneath. No need for fancy power generation. The drop will generate the current wich could be registered by any microprocessor just let the pin be an interupt
@@DereinzigwahreAkede Thats what a gravity-clock mechanism _is,_ congratulations!
A survey drone is my best guess (Lidar on a UAV) which flies the track ahead of a train. That results in a point cloud of heights which can be very accurately geo-located, and that then turns the rock problem into a relatively simple bounds check in software. Even a £5k commercial drone is likely a lot cheaper than maintaining their current setup. Or an even simpler one: just stream the video from a drone to the human driver of the train.
I've travelled on this line many times and I had no idea there was anything like this going on behind the scenes. I've a new found respect for Scotland's railway men and women.
Anderson's Piano would have made a great subject for the Technical Difficulties. That is all; carry on.
Two of these people are lying: What is Anderson's Piano?
You have to search for "Pass of Brander stone signals".
I'm now hearing in my head Gary saying the words 'Anderson's Piano is...' with the unshakeable confidence of a master BSer
It's an album by Brian Eno of Scandinavian folk songs played on a prepared piano.
@@Nimelennar Anderson's Piano is a Finnish torture device
I wonder why they haven't written a manual on the maintenance of this system? Sure, a lot of it is probably fiddling with it (in an engineer way) until things work properly, but there should be no barrier to writing out what the general methods are, and the "DO NOT DO THIS UNLESS YOU WISH DEATH" warnings.
Exactly what I was thinking. Obviously its a complex, manual system, but tons of far more complex systems have written manuals and videos and the like to give information on said complexities. Seems strange to have this information be "passed down" from year to year as if it would be impossible to create a guidebook that supplements physical interaction with the device.
Would be like a 50s car just having absolutely no written documentation on it, simply because theres two guys around that know how to work on it and they'll explain it to you if you ask.
documentation is a myth you learn about in uni that doesn't exists in the industry
There likely are a few maintenance manuals for it, written a century ago, but the parts that they used in there are, for the most part, either long obsolete, or were all "house made" by the local steam train service shop, using the blacksmiths and boilermakers there to manufacture them all in house, along with railways carpenters that made the wooden aspects of the system. Kind of hard to replicate without a large forge, power hammer and a lot of skilled craftspeople to do the various aspects. You are not going to buy the parts off eBay for this easily, and most hardware stores will look on you in puzzlement when you ask for a sixpenny nail or a tuppence one.
I suspect that that was a bit of hyperbole. They probably have written a manual. And yet, as a carefully balanced mechanical process involving carefully balanced tensions, counterweights, friction, etc. there's probably a reasonable element that you can't learn just from reading a book. I expect that you also need some hands on practice with the system to learn the practical skills to turn written theory into practical results.
I'm sure they have, but it's obviously not been written by whoever designed/built it originally, which is how modern systems are documented. It means you can still get unforseen and undocumented problems which need a fundamental understanding of the system to solve.
The fact that Tom consistently, week on week provides an extremely interesting video about a subject I would have never thought about before is magnificent.
Thank you Tom for all that you do!
Also, that van that can also drive on the railway is beyond cool!
Bot
@@actuallypings7940 alright mate, whatever you say….
@@actuallypings7940 it's not a bot
Not anymore :(
I don't know if Tom realizes how much his videos make people like me want to visit the UK.
Those Scottish landscapes look absolutely gorgeous.
From Edinburgh head north, take the A9 past Perth, hang a left at Dalwhinnie towards Fort William. It's about 3-4 hours and takes you into the scenery you're going for, if you ever decide to come :)
@Teamgeist Depends what time of year and what altitude you're at. In summer the land around the lochs and down in the valleys can be stunningly green.
Visit Scotland! You'll love the different landscapes. Expect vast areas of green and also areas of nothing interesting, so to speak. When I went to the Highlands, I was told to expect not that much but I enjoyed the day tour going to water falls, glens, dams, castles, etc. Scotland is really a rather amazing place to visit. Don't forget to try the food - I can't find good haggis anywhere else!
Scotland has been on my wishlist for a while, if only for my enjoyment of Scotch.
@@nolyspe add distilleries to your itinerary if you're inclined to the process and drinks
It's actually a bit funny to imagine someone from the rail service ordering new wire for Anderson's Piano starting with the line, "I need 100 metres of your weakest wire"
Ahahahaha
@@hairyairey You could pay a lot to have it coated with anti-rust stuff or something. Wouldn't be economically viable though.
@@hairyairey or you could just coat the drums in oil.
Simple enough, you take a few dozen samples of the original wire, and send them off for tensile strength testing. Then you get a nice set of figures for the tensile strength, and the elongation at yield, plus a plastic deformation load. then your request for supply goes out to your suppliers for a wire, coated with zinc, like most wire is, that is within 10% of these 3 parameters, and you get the result back. Choose a supplier and order 100km of the wire, test on arrival to ensure it complies, and place a few rolls in the local stores area, ready for use there. Not at all difficult, and while the new wire might be a little thinner than the original steel, due to improved steel making resulting in a higher strength steel, it will still fit the old mountings and apparatus perfectly.
@@KurtFrederiksen the wire gage doesn't matter as much as you think it do
I'm a train operator in the US. I can completely understand how this system would still be the best. Sometimes it's an old solution or principle that is the most reliable in terms of energy requirements or practicality.
Also, I can definitely vouch for the dangers of larger objects. It takes a lot to derail a train but sometimes, all it takes is a cow or a deer. I've seen it both ways.
I've been wondering why there aren't just plows on the front to knock objects off?
@@blazerorb not all objects get pushed out of the way. Most locomotives have some sort of plow, but they are different from the cliche cattle-catchers of old locomotives
@@SupernovaSpence this is fascinating altogether, but I'm wondering exactly what you mean by "not all objects": are you referring to just particularly large and heavy things, like Alastair the engineer's example of a washing machine, or can smaller stuff like, again, microwave oven-sized rocks also 'bypass' a big, front-mounted plow?
@@SupernovaSpence unless your in a canadian winter . A freight train with a snow plough is a site to behold in heavy snow.
And if there is a snow bank you back up so you don't get blasted off your feet from the oncoming snow eave
@@mnxs I guess, depending on size, weight and where in relation to center of mass of the object, it could go to either side, or under the plow. The plow probably can't scrape neiter the rails nor between them to push everything away, for the same reasons our toy cars got stuck when transitioning from the back rest of the sofa to the sitty bit. Trains also have some "slightly" more gradual transitions like that :)
I just think that this proves that trains and train related devices are already near-perfect. I mean whenever someone tries to reinvent transportation, it just ends up coming back to trains one way or another.
What I'm saying is that trains are perfect and awesome machines.
also wheels are overrated because of one thing: you need roads
Says who
@@ramankhmel2094 trains have wheels?
Sheldon Cooper approves.
@@ramankhmel2094 wheels are surprisingly optimised.
There are so many critical systems built today that aren't built to last 10 or 20 years, much less 100+ years. I hope the lessons and work of engineers and construction workers from back then survive our modern 'build it as fast and cheap as possible' mindset and thrive with a new generation.
That said, the mindset and detail-oriented designs of past decades, applied to the technology we have today, could result in systems that are as robust and resilient, while also cheaper to maintain. We just need to back off a little bit from the "always choose the lowest bidder" option.
Agreeing with you.
@@kroezelgaming Second that.
I think the main trouble is that parts are outsourced or designed by specialist companies. Those companies have it built into their business model that they want/need the ability to sell replacements/upgrades to the same people in years to come.. so it's in their interest to manufacture parts with a lower shelf life. Very hard to police that. Somebody who worked at a power tool company said that they literally *could* make a motor that would last 50 years, but the design it to only last a fraction of that.
Rpi controlled railway signal system here I come.
@@kroezelgaming forth that
140 years, the ABSOLUTE definition of, "if it ain't broken, don't fix it"
A system that functions in a way that it's actually MEANT to break is in fact the best idea to give a real warning...
I hate that expression.
@@Krytern well so I was going to say the expression seems a bit misplaced here and I also can't stand the use of cliché expressions when they're not thought of, just use them cause they're common sayings or expressions... Cause it makes no sense in this case it's more like; if it breaks it means it's working... Allthough it does make some sense in the way of saying; if the system that way itself ain't broken, no need to replace it cause it works well... But even then "if it ain't broken don't fix it"? Nah, it functions the other way around; if it breaks don't fix it cause it means there's probably rocks on the tracks... So uhm yes I get it. Pardon me Rich G, I understand what you mean to say but I disagree with saying it's the ABSOLUTE definition... It's VERY relative in this case I'd say. 😉
Rock: “if it ain’t broken, don’t fix it”
Tracks: NOOOOooooooooo
@@Krytern why? It makes sense, if something isn't broken, why bother to fix it? It works
I work in an underground mine in canada, and we use the same type of "tensioned rope with a flag at each end" system to monitor the beltways that run underground. It works, and it makes it easy to find a problem. You just drive until you find a flag up.
Just like the mail, with fewer pulleys.
6:18 The train’s musical accompaniment to “Hey, couldn’t they just…” is excellent.
it's like the train was saying at that exact moment, "nope, shut up"
I love train watching in Scotland . Old school semaphores , Manned interlocking towers , friendly employees and spectacular scenery . Well done !
0:47 It took me a minute to realize "as small as a microwave" didn't mean "between 1mm and 1m". Although, I guess that technically still fits.
Same 😂
Wow, mad props and respect to the people who work to deal with this. There's a lot of teamwork and cooperation involved in just making this work.
It's a terrible system let's be honest
A. Congrats on check
B. You changed ur pfp this is not okie dokie
Still used in parts of Ireland. Plenty of archive footage going up until the mid 2000’s
You again
ohrly...? so as with any railwy, or infrastructure...?
The timing! Wow!
It's soo perfect
I thought they must've set that up but it just wouldn't be realistic. So perfect!
The timing rivals James Burke's shot of a rocket lifting off
@@munkeypantsman that's what I was gonna say!
Tom loves trains, and landslide warning videos.
And so do we, or at least I hope so (in moderation).
Tom the tank engine explainer?
I like the size comparison to microwaves and washing machines, rather sensible. And the timing of the Sprinter at the end there was impeccable!
Also was quite surprised Geoff didn't make an appearance here :P
Interesting bit of kit too, think I've heard of it before but never really looked into it.
"small rocks" and "size of a microwave" in once sentence was quite funny though
@@jojodroid31 Indeed, if that's a "small" rock, then they _really_ don't want a train to hit a big one. 🙂
I thought size of a microwave as in the wavelength of frequencies in the 'microwave' range until i noticed hes talking about an actual microwave oven 😅
In urban areas you get microwaves falling on to tracks.
for real dude. unequivocally correct
There is a similar tripwire system used at the eastern end of Southend Airport to protect against an aircraft running off the end of the runway and onto the railway. If it's tripped, the approach signals on both roads are dropped back to red and it requires a physical re-set afterwards.
(Presumably Instruction No.1 of the local procedure reads something like "Check for bits of burning aircraft on the railway".)
And if it's NOT burning, but just in pieces???
Exactly the same problem exists for conveyor systems - pull wire switch monitors exist to tell operators exactly which switch is tripped on 20 km conveyor systems with a switch every 100m. On conveyor systems they still need local resets because they are a safety of life system but simply knowing which of the 400 switches (they are on both sides) has tripped is a massive time saving. The radio transponders use lithium batteries that are changed every five years.
Tom your timing is always on point! I would not be surprised if that was planned :D
Must’ve waited a long time for that train
@@gwyneddboom2579 probably 30 minutes to an hour xD
you can look up when the train is suposed to come
@@burgerpommes2001 that relies on the train being on schedule
@@richardmillhousenixon any delays also show up online
Love trains, all the best from Finland to the dear Scots!
Tom really has impeccable timing for things, like if every person has magic in their own way, that must be Tom's magic.
Or enough takes
Except icelandic volcanoes...
@@Game_Hero Iceland really is his weakness, between the volcano and the Icelandic-Mexican fusion cuisine.
His intonation on "hey, couldn't they just…"was even in tune with the train's horn. How???
Volcanoes and giant metal dome sculptures (elia)
Petition for all physical hazards to be measured by the Scottish Standard "Microwave to Washing Machine" Scale.
I am still struggling with the wavelength of washing machines...
I was thrown by "Something small like a microwave"!
@@Thisisace a very sturdy train to not be bothered too much by a rock the size of a microwave
I was thinking "Well don't let microwaves and washing machines on the track"!
where does a full landslide fall on this scale?
Very well done. It’s a real treat being able to view parts of Scotland’s railway system. American railways are built on the foundation of what was created in your land so long ago. Love the semaphore signals! I’ve visited Glasgow and Edinburg, but I would love to see the whole country; especially all that lies to the north of G & E. What a lovely country!
I love how the guy went "We don't need them to be stronger; we need them to break." Sometimes, improving on something has a negative effect on the current needs huh?
@miko foin That can happen with this system too - in fact in 1949 it did
That happens when you buy something that has not been made to the specification you need, but just has them by chance.
IIRC, there was something similar with Mercedes. Unlike their competitors, they were still creating the turning signal noise only through the clicking of the relays while others were using dedicated tiny speakers. Worked well until the relays were changed in some way and did not have the familiar clicking sound anymore (because most manufacturers do not have consistency of clicking in mind when optimising durability etc)
ok time to pipe it down, buddy. obviously improvent is realtive and always in regards to the needs.
No, improving something has a positive effect on the current needs, it has a negative effect on past needs
I know about similar situation in NASA, when they had used shuttles, they were purchasing emergency ladders, and, at some point manufacturer decided "let's improve our materials" and changed fabric to more strong one, wich is also more slippery for space suit. Astronauts didn't know about this during training, so one of them even gained trauma because of fast descend and following collision
During Christmas 2016 I got stuck for an extra overnight at Kyle of Lochalsh (that's on the northwest mainland looking over to Skye) due to a landslip disrupting the tracks. The wires broke, word got out and my train was cancelled.
Spent it in a cabin looking out to a ruined castle during a storm, with a log fire going and history books to read by the window.
The system works.
PS There was a battle at the Pass of Brander / Cruachan area in 1308 where Robert Bruce and James Douglas ambushed the Macdougalls by climbing over Ben Cruachan. The more you know!
it could still be improved , it could send a bottle of the local Talisker whiskey to your cabin and have you boss phone you to say you can take another week off and have a pay rise while your at it.
This system isn’t used on the Kyle line. That part of the word it was likely a roach fall incident, we have them fairly frequently despite nearly annual work installing mesh over the cutting faces
As a happy passenger who's been lucky enough to travel by train through the Highlands, I'm grateful for this technology! And I highly recommend this trip to everyone, it's spectacular! 🚂❤️
I find it amazing how many big institutions rely on "tribal knoledge" passed down previous employees to newer ones. The inability to store and access legacy information on processes and equipment is a major problem that needs to be addressed of we are to operate in a world of very long life systems.
Tacit knowledge I guess
OTOH, it provides some employment security. People can't be replaced without being able to pass knowledge down. You might be surprised how entrenched this thinking is, and it's not without some justification. Before presenting "solutions" from on high, you have to reassure employees that it won't make them redundant. Especially if you're actually trying to make employees redundant.
@@squirlmy OK, but what happens if the person with the specialized knowledge dies in a sudden accident? There's no harm in having it written down or otherwise codified so that the knowledge is not lost.
@@chrysshart I would say for this specific application it's a team of people so the likelyhood of them all dying in a freak accident is slim. Most modern businesses that use general labor have a written S.O.P for the task, but I would consider this a niche case.
@@chrysshart You are right, there is no decent reason why this system couldn't be documented to a reasonable level, of course anyone working on it is always going to need a fair bit of common sense but its not hard to write down a decent crash course in its operation and maintenance.
I love this mix of the old and new technology he's talking about, the balance of what works and what's innovative and potentially more capable, with an eye to geography, weather, and what's possible. That's the right mindset.
Railroader for eight years here.
I worked in Montana for a while and we had these for a section of our track which was adjacent to a rock face. I have personally only seen this system set off once before which was for a fairly large rock that got through, but wasn't on the actual track. There's also a permanent slow order through that zone which was 30 mph.
If it works, no need to fix it. The fact is that many of the technologies used on trains and track is decades old, some of it over a century old now.
This concept is widely used in the US, except it's generally based on on an electrical current passed through the wires, and any break is detected and alerts the Dispatch directly.
It is mechanically much simpler, just wires stretched on insulators, but this is unique in that it does the job with no power required.
If it were me, I would put a small telematics box at each signal that sends an alert anytime it is tripped.
If the cell network is available, they can last 5 years on a lithium battery because they don't actually use power until they are tripped.
If you only had satellite available, a solar panel and battery pack could keep it going the majority of the year at least, and you add this to the mechanical signal so even in the dead of winter if the solar system dies the train still gets a warning.
But having the remote alert would allow track workers to respond as soon as it happens, rather than only after a train reports it.
On the other hand, maybe there is a train through there every half hour, and adding a remote alert would not gain anything!
Send me a link
unfortunately, setting up such a system would be a large investment, one which perhaps the government, or even specifically the rail administrators, won't see as worthwhile, certainly not in the short-run, not while they can make do with the current system. Unfortunately politics, inter-administrative, national and local, plays a huge role in these matters. On the other hand "don't fix what's not broke" also has a certain wisdom to it. This particular system has worked 140 years, can we be reasonably sure cell network or satellite systems won't have unforeseen issues that negate the benefits?
For an electrical system Wire would be 5-6 grand, electronics would be a grand per box, times 4 (for redundancy), so 10 grand
The advantage is that you can just solder the wires back to reset.
Though another option would be to keep the existing system and just add a monitoring device that checks the state of the flags and reports it immediately.
Very poor radio reception for aught above MW up that way. It's not that far from glencoe... Which can't get terrestrial tv signal. Back before Iplayer etc TV licencing repeatidly took residents who had sky dishes to uk court, despite EU courts each time overruling saying that as no terrestrial service... Tv licencing was (fraudulently) attempting to charge for a service they simply didn't provide at that location.
@@satibel the cost to run copper wires then you have maintenance cost old system vs new system.
for this salutation it honestly makes more sense for the train driver to go slow during a warning
Alistair could announce an impending apocalypse and I'd still feel calm
Its why a lot of call centres in the UK are in Scotland as the Scottish accent like this can be very calming for people.
I would not have panic attacks before calling customer service if I knew Alistair was on the other end of the line.
Nathan Evans: am I a joke to you?
Impending apocalypse.. did you mean recent days or last year?
@@JaleDoris Ha ha, yes! I always seem to get that angry sounding chap in India who is clearly reading from a script😂
Thankful for all these great minds and people who essentially keep the world running smooth.
Thanks for another great video & effort Tom!
I love the environmental side of this. You're trying to upgrade a system, and you're not allowed to use (much) power. Having that reminder that not everything needs to have a million sensors and a self-learning algorithm is kinda nice.
There would likely be a net environmental benefit of installing a power hungry protection system becausse it would make the railway more reliable, displacing cars
It's not an environmental issue. It's more of a "this railway is out in the boonies and there is no power available" issue.
energy is a finite resource, for now at least.
@@sublivion5024 Seems like that'd depend on a bunch of factors. A railway monitoring system would use, give or take, the same amount of energy per mile as any other mile, but a more remote section of track would be relevant for fewer people who aren't already using it, and at a certain point, running a system 24 hours a day, 365 days a year is going to be a bigger drain than is offset by X extra loads per year of people and cargo.
Remember that it is being used by some already, and the system seems like it works, for the most part, so the reliability can't be too great an issue.
The power used for this is almost guaranteed to be negligible from an environmental perspective.
Love Victorian era railway engineering, the ingenuity applied to problem solving without electrical and electronic systems is amazing.
Having said that, as an old hand Signalman it came as a bit of a shock to see non absolute semaphore signals with red arms
Was it a good job
@@oscarosullivan4513 was and still is tho I do miss the exercise these days. Sitting in front of a bank of monitors doesn't have the "feel" of 192 shiny steel levers and panoramic windows
I adore analog engineering
Digitals great and I wouldn't want it to disappear.
But it's not as satisfying as analog and you feel like making it is more of a challenge
Ah Tom Scott doing the work that the discovery network once did and perhaps should still be doing. Great work as always Tom.
"Something as small as a microwave can cause a train problem, something as big as a washing machine could lead to derailment..." I guess they have problems with domestic appliances tumbling down mountains in Scotland!
Normally followed by a Scotsman hoping to grab all the copper wire out of it as well, to turn back into a penny.
A few years ago some volunteers cleared a lot of the human debris left at the summit of Ben Nevis, Britain's highest point, and well visited. Among the items they had to deal with was a piano, thought to have been carried up there as a prank by some students ! Throwing it over the north face was not an option ! (No, it wasn't Anderson's piano !)
@@tonydarcy1606 Easy solution for the piano. build a trebuchet at the summit, fling the piano off the mountain (and PLEASE record the sound, for comedy).
What's that? Now there's a trebuchet on top of the mountain? Bah, details.
"Is it bigger than a breadbox?"
Please recycle, people!
For those wondering why the double-semaphore has one painted red and white. A signal is painted red on one side, or yellow if it's a distant signal (iirc), and white on the other. Train drivers facing the red or yellow side must obey the signal's position, but facing the white side the position is ignored.
Maybe that line runs in both directions?
@@robinbennett5994 yes it does. Single bi-directional line
@@robinbennett5994 It does, that's why there are two signals. One for each direction. The line uses a Single Line Token Block system to ensure two trains aren't occupying the same track in opposite directions.
Line runs both ways
@@robinbennett5994 re-read the OP. Of course it runs both directions. I'm not sure how you missed that. 🤗
Wow that's amazing, I have hopped almost every mainline in America. I would love to hop through there it looks gorgeous. I love old analog tech, especially in the train sector.
Sometimes an old solution is still a good solution, or at least "good enough for now." I'm willing to bet whatever technology eventually solves for this problem doesn't last 140+ years like this has.
"The simplest solution is often the best solution"
Indeed. It's also less susceptible to becoming obsolete. I mean, there are some pieces of industrial equipment I've seen that still need Windows 3.1. Meanwhile, something purely analogue like this doesn't need to worry about that sort of thing.
If whatever tech replaces it doesn't last 140 years, that would probably be because technology advances faster now, and will probably advance faster yet in the next 140 years.
They wouldn't last 140 years, because the companies making them don't want to ;)
That speaks more for the current rate of technological development than for the imperfect, affordable solutions of the past, though.
"small rocks can be an issue for trains"
"huh never thought you'd be able to stop a train with a pebble"
"rocks as small as a microwave oven can be problematic, washing machines sized obstacles could cause derailment"
oh
On the North American rail network, the lines carry an electric current. When a rockslide, snowslide, or other avalanche breaks the circuit, it triggers a red signal on the track and alerts the control center (which is often thousands of miles away).
This is for stretches of rail where power sources are not available or not economical. As one US train driver commented, they use a system like this in remote areas in the US.
In the UK, electrical signaling goes everywhere the trains do, so not a problem, however a mechanical switch at each wire could be tuned to alert central control if the wire is broken or pulled, with different alerts per direction . If something is leaning on a wire (pulled), an investigation train can be sent to identify and remove it . If something bigger breaks a wire, investigation train also needs to install a new wire and reset the tension to return the sensor switch to middle position .
One advantage of such a basic upgrade is to signal trains to slow down before reaching the alarm area, with all the modern procedures of other temporary speed restriction signals .
Sehr altes und nicht gerade überzeugendes System. Gehen sie zur SBB (Schweizerische Bundesbahn) und schauen sie, wie diese hochmoderne automatische Technik funktioniert.
But if the current is in the rails, wouldn't this only work if a rail is actually broken??? And if so, might it not miss a rock or a pile of snow which obstructs the tracks but fails to actually knock a rail out of place???
The current isn't in the rails. It's in wires strung along the side.
"something as small as a microwave could cause problems to a train" for a moment there i was mesmerized about how a wavelength could cause problems to a train
Well, those too!
Glad I'm not the only one who had that though
Me too
"There's not a user manual or a downloadable book on how to maintain Anderson's Piano. We need to pass that down through generations of technicians and engineers."
Have those technicians and engineers considered making a user manual or downloadable book to make that process easier? :P
They're modern engineers so you can't expect them to do something easy and obvious.
Exactly what I was think! I love reading and writing manuals. I'd come down to Scotland, ask them how it's done, and then write a manual for them
Job security.
I find most engineers can’t write. I’d love to help.
The way it looks, the user manual would be "cable go breaky, fix it"
When I saw the thumbnail, I thought you were talking about semaphores. :) I was confused because there are regular lighted signals on certain railway lines these days, not just semaphores. The mechanical rock fall detection system makes more sense (and makes a lot of sense for needing to use semaphores :) ).
So did I
lit not lighted. Poor English there!!
@@markylon That would be "regularly lit" as in frequently, or with a constant time interval. "Regular lighted" might have needed a comma ("regular, lighted"), as they're both descriptors of the signal style, and indication that "all" signals contain nighttime illumination of some form or other, these days.
Fascinating as always. When I saw that last train coming by I thought "Wow, Tom really did a great job of setting up and timing that final shot!" Little did I know . . .
wdym Little did I know? Wasn't it timed?
"A UA-camr in Network Rail PPE looking at railside engineering" usually means Geoff Marshall, these days. Good to see Tom getting some of the action.
Was slightly surprised that Tom did this rather than Geoff, especially seeing Geoff's Network Rail collabs of recent!
@@fetchstixRHD I've watched a piece about "Anderson's Piano" somewhere before and ironically I think it was on an episode of Scotland's Scenic Railways that also featured Geoff and Vicki travelling to Corrour.
I consider this one of the best short descriptions of a technical device on UA-cam. Thanks to a cleverly setup of introduction, questions and moderation, it is the thoroughly thought-through text spoken in on and off of the railway engineer that does one make interested in railway design way beyond the pure coveredge of the 'Anderson's Piano'. So, thank you for it from Austria. /wp
0:37 is an incredible, incredible shot.
In a similar vein, the 1800s telegraph city-wide fire alarm system still used to this day in Boston USA because it just works.
We had one of those in parts of Houston, but they must have phased it out. I haven't seen an alarm box since the nineties.
San Francisco uses the same (incredibly clever and robust) system. Unfortunately they seem to be having some trouble with maintenance due to the age of the system. There was a news story a few years ago that they ran out of "out of order" notices and had to resort to duct taping red bath towels over non-working pull boxes.
I think this is a good example of how undervalued experience and knowledge have become in the modern world.
Given the amount of avalanche and rockslide detection systems here in North America I’m surprised none have fitted the needs in Scotland.
Also, the continuing past a “danger” signal exists here in Canada; there are two in fact: “restricting signal” and “stop and proceed signal”. Essentially, you continue at a speed below 15mph at which you are able to stop at half the view range distance (ex. You can only see 500 meters ahead so you must go at a speed in which you can stop in 250 meters). These are usually in automated CTC (central traffic control) portions of track that operate by the axels of trains completing a faint electrical circuit in the rails to trip signals and usually give this indication if there is a grounding of current or a cracked rail.
Given the average speed of tracks in the US and its infrastructure grade of D- I wouldn't be surprised all these brillant systems imediately went into the bin
They aren't detecting avalanches or rockslides, just the stray rocks that can cause a lot of damages despite their relatively small size.
A similar thing exists in Hungary for block signals, since they're generally out on the open track where station personnel isn't available to check that the train can pass safely despite the signal showing "stop" (danger). In general, the engineer has to wait for two minutes before proceeding at no more than 15 km/h, but the wait isn't required if on-board signaling is available and if the on-board signal shows clear beyond the signal, they engineer can speed up.
(I'm glossing over nuances here for the sake of brevity)
I'm quite sure that Tom Scott was a bit mistaken on the 'always stop on red'. Google "permissive signals". Those exist in many countries, including countries with a quite modern rail network such as The Netherlands.
In the UK are signalling system is not speed based signalling but route based signalling. The line is signalled under RETB=Radio Electronic Token Block. You simply add a Semaphore calling on Indercators in the form of a mini Semaphore signal.
Ironically the issue of not having power in remote areas also plagues the power grid.
If you're trying to set up a SCADA system in the middle of nowhere to measure current flow it's going to cost $10,000 just for the transformer that gives you access to 120V/240V power for your computer systems. That's the best case scenario for an issue that by definition is under an existing power line.
Wouldn't solar power be a good idea? Where I live there are ton of flood gages. They are all solar powered and talk to Flood Control over the cell phone network. There's even a website where regular folks can check levels.
Full SCADA systems are no longer needed. That’s the “revolution” of IoT. Sensors, computing and communication are now very cheap.
@@Bacopa68 It is a good idea but only as long as the sun is shining. At night or on a cloudy day propably not so good.
Probably still cheaper than running another cable with 240V! I imagine solar cost/efficiency + battery + ever reducing watts/hz in computing gets you over the bar with sufficient reliability margin in a growing number of cases as time goes by.
There’s plenty more instrumentation manufacturers could be doing to reduce power consumption and reliance on a town power supply. None of that equipment -needs- to run on a 240V supply. Open it up and you’ll find a Switched mode supply giving you 12V and 3V3 DC rails.
@@Jonny_24 there's these crazy things called batteries. I think they might solve your problem.
That was cool to see. Thanks.
I love how Tom keeps finding interesting things in the UK to talk about. It makes me want to visit the UK to find out what interesting things I can find.
That was great timing with the Class 66 at the station and later the ScotRail Class 156. I'm always pleasantly surprised when Tom uploads a railway video.
That was very well and clearly explained. Good interview!
I’ve lived near there for almost 20 years, and I never knew about any of this! (Only thing that comes to mind for that railway with me is the derailment that happened in about 2010)
On that occasion the rockfall slipped under the wires, so they didn't break
@@Inkyminkyzizwoz ah right! I never knew too much about it to be honest (I was 10 at the time)
This kind of videos, very informative and interesting, is my favourite thing to watch. I really enjoy learning about various things you show and from interviews with people working there. And your thought add a lot. Thank you, Tom, for making it.
I feel like I just listened to the most knowledgeable person on earth and I could listen to them all day
Permissive signals, where after they're at danger you're allowed to proceed anyway just slowly and within sighting distance, are very common worldwide. France and the Netherlands are full of them. Britain is actually quite unusual in not using them anywhere.
Nope, Britain has permissive signals in a lot of places too. Usually they're used for things like allowing a train into an occupied platform block section in situations where it is supposed to couple to the train already there.
People who know very little about a subject making a YT video about it? Couldn't happen.
There's lots of permissive signals in Britain, or else you'd never be able to couple two trains together or have two trains on the same platform.
@@PinkThorn242 That's not even remotely the kind of permissive signal being talked about though?
I was under the impression that if the shunt signal beneath (if there is one) shows a "proceed" aspect, trains may continue at shunting speed even if the main signal is at danger. As other have said, they're mostly found near station platforms and railyards.
As always, impeccably timed and narrated. Reminds me of the other rock detection system in place, you covered last year (?), with the traffic lights on the road, albeit, this is longer and more complex in needs!
The timing at the end honestly put a smile on my face.
That timing was incredible
Having passively active systems that don't require power is just great. I whish more solutions with less or "other" power would be used. Electricity and computers have become the common standard, but aren't necessarily the best option. Thanks for this intriguing video. :)
Dear Tom Scott
I am from Bangladesh,my father was Bangladesh Railway worked as SIGNAL ENGINEERING so called inter locking system and wireless system,so far I loved RAILWAY,your presentation is realistic,thank you,wish your stable health plus waiting for the next presentation.
This failsafe system kind of reminds me of the one in industrial looms. A piece of metal shaped like an upside down U is put on every thread of warp (that's thousands of them) and should one break, the piece of metal falls on a special surface underneath closing a circuit. The stop is automatic, though, unlike in this video's case - it makes the loom halt and shows an error. Unlike the trains, if an industrial loom continues weaving, even slowly, after a string of warp tore, it's a problem.
Similar: High end kitchen mixers have a critical gear that's made of plastic. It's designed to break before more important (and more expensive) parts of the engine break if you over-work it.
@@ItsMrBozToYou and now they have table saws that fire a charge to stop the blade nearly instantly, when there's something conductive touches the blade. There's a video on UA-cam that was done with high frame rate cameras, and using franks in place of someone's finger. The stopping power is so effective, that it tore apart the teeth not in contact with the brake on dado blades. It works much like air bags in a vehicle, but slams the blade rather than inflates a bag.
But those things also always remind me of humans and tchernobyl: we dont know totally whats going on but lets ignore warning signs, surely everything is alright and they can be ignored, the warning just is wrong.
Crazy what even so old engineering could accomplish so reliably
Ikr
If it ain't broke....don't try and fix it
Planned obsolescence is a big problem for the commercial world. Less so for the industrial world, but still very much a problem.
If you want to see something REALLY crazy, look up analogous computers to calculate tides.
@@Shuizid YES, the veritasium videos about analog computers are really well made!
A very nice video, thank you. It's about the same over here, for slide/fall detection. Very much more integrated with the signal system and dispatcher, but a fence is a fence at the guts of the system!
I worked with the railroad for 39 years and I will say that "If it ain't broke, don't fix it" is a viable option in considering system changes or upgrades. Every system/option has its trades.
Reminds me of how the lights for the railway crossings here still use mercury switches, even though they've been banned for almost everything else, because they are just so much more reliable then any other electronic system.
how much more reliable is a mercury switch compared to a tilt ball switch?
I suspect they bounce less (as in contact bounce), and there's also less trouble with contact pitting from arcing (because it's liquid)
This video reminds me of the one you did in Switzerland with the boulder detecting radar connected to a traffic light. Thanks for another great video.
In Germany we use the same system still today. It's called "BALA": BoschüngsALarmAnlage". Word by word translated something like "embankment alarm system".
We use it not only for rocks but also as detector for levee slides after massive rainfalls.
The only electric thing in the BALA ist a simple box in the office of the signal dispatcher which screams loud as hell, when the steelwires on the hills lose their tension.
Tom, again a great video! You really have a gift to find these stories and the people who are so invested in their jobs - the Scottish engineer in this video or the Germans from Deutsche Bahn from the training center for signal workers (?)!
That the "Anderson's Piano"-system operates to this day has something to do with a railway safety principle. That principle is simple: a railway track wich is free from trains gives a continuous electrical signal to the main safety system saying: I’m free, trains are welcome. When a train is on the track, it shortcut this signal and the main safety system puts the signal that gives access to the track on Stop. This safety principle has also the effect that when there is a malfunction, the main safety system always keep a signal on Stop. It’s also known as "failsafe".
The Anderson's Piano-system is based on that same failsafe principle, but instead of a continuous electrical signal, it uses a mechanical continuous signal in the form of a wire. If a wire malfunction, the connected signal falls down to Stop.
Replacing this system gives two main challenges: making a system that is failsafe and making that the system gives less false reports than correct reports.
The modern world is starting to use axle counters instead of electrical track circuits. They are not prone to electrical leaks and other insulation problems. Same number of axles in and same number out -> track is clear again.
There is drawbacks though. Axle counters can't detect broken rails, but with modern rails that's not too big of an issue anymore.
@@laju axle counters also lead to fun situations where trains are not allowed to have particular numbers of axles. IIRC there's at least one place where trains are not allowed to have a number that is 0 (or possibly 1, I'm blanking on the exact details) mod 256 because they only use a single byte for counting and they don't check for overflow 🤦♂️
The trains shortcut the signal from one track to the other? Fascinating
This is even a safety feature for rail crews. When I worked on the railway, they issued 2 metal clips connected by a wire (essentialy oversized jumpleads) as part of safety kit on every train and in every van. As part of safety training we were taught if there was ever an emergency on the line which required the stopping of trains to prevent further incident, use these clips to connect the 2 rails together. This will immediately set all signals to red and so stop any other trains proceeding into your area.
Of course this works both ways. You also have the vandals who know about this and purposely put a metal bar across the rails just to cause havoc!
They still use something similar in the US along certain routes. I rode Amtrak from Omaha, NE to Oakland, CA in the 90's and along the mountain passes from Denver to Sacramento there were multiple wires stretched along beside the tracks. At that point I had no clue what it was but learned later on that they were there to detect rock falls and such. It's an amazing trip going through the mountains for sure though. I went through in December headed west and January headed east through those area's, something I truly want to do again sometime.
Funny enough, Just last week I finished my Canadian railway signalling course. Over here, there’s actually a few signals that abide by the same rules! If they’re set to the most restrictive aspect, you must proceed at a speed that allows you to stop within half the range of vision of equipment, not exceeding 15 MPH. (I know, we should be using metric) and be on the lookout for broken rails/track washout. Neat to see that that rule is somewhat implemented across the pond!
Despite the UK being metric our roads and rail still use imperial for distances and speed for operations. Metric is used for surveying and design
@@qwaszx2 How is Fahrenheit superior?
@@Inkyminkyzizwoz Fahrenheit is superior in the US as there is an entire body of knowledge referenced in US units. All just available from countless standards and tables.
I was wondering about Canada, having driven along the highway through the Canadian Shield in Ontario and I'm sure rocks have been a problem for trains over the years.
This is fast becoming one of my favourite channels. Always such interesting and fascinating videos
Thanks for having subtitles👍
Another fascinating video. Alastair's descriptions and explanation of the systems was excellent.
I like this video, it has a good point. The fork is thousands of years old and chopsticks, older. Sometimes you don't need to update
It’s amazing how much upstate New York and Scotland look alike. The rivers cutting through mountains on both side and the utter bleakness in winter. Fantastic.
Scotland shares geology with North-Eastern North America as they were joined at one point so that would make sense
One alternative, which is currently used for some infrastructure in the UK, is a fibre optic sensing system. Essentially very similar to this, except instead of cables there's fibre optic wires. It'll generally detect an issue before the rockfall happens, because the wire will measure increases in strain at every single location on the wire at high resolution, and can pinpoint exactly where the issue is.
If it wasn't for Tom's reaction at the end, I would have said this was a perfect James Burke timed piece to camera :)
Fascinating, especially also what methods they use to keep rocks from falling, or in other instances, to at least catch them before they reach the rails!
I thought this was a Geoff Marshall video for a second. I love everything trains. So, this was absolutely fascinating to me! Great video!
His videos are great too!
“As small as a microwave” that’s a big fricking rock
But not as big as washing machine sized rock.
Maybe they have very tiny microwaves in Scotland?
really saying som about the “big” rocks, isn’t it?
@@quillaja They’re micro-microwaves.
Anderson's Piano... Definitely never heard of it, but it's simplistic and brilliant. I went on to research this more on YT and this was the only video about it. Well done!
I wonder if they set the tension for c1 or g1, with a precision fork, but may be h is b in your system, that's a mess, and the question is baroque or modern intonation, so do re mi fa g-enius! For windspeed, they use chimes ...
It's interesting-there are places on the Pacific Coast Highway in California where they use the same kind of restraints to keep the cliffs from sliding down onto the road. And since for a lot of places on the central coast, that's the only road into and out of town so if that's closed, there are huge detours to try and get to the town from the other direction.
Got to admit it's a bit weird hearing recent videos describe places in Scotland like Oban and Helensburgh as being in the south west, and Fife in the south east. I mean technically they are south of the geographic centre - but no one from Scotland would say "in the south west/east" for these places!
That timing when you ended the video and the train passed was just so perfect :D
The timing of the train at the end is so satisfyingly perfect.
Scottrail.