Why November is the most dangerous month for trains
Vložit
- čas přidán 12. 11. 2018
- Sponsored by Southeastern Railway. Are 'leaves on the line' really a problem for trains? I investigate the famous excuse with some ice skates, a jar of pectins and a blow torch.
For more info from Southeastern: bit.ly/2CvBsLX
Animations by Dom Burgess. His brilliant channel, Every Think, is here:
/ @domburgess
Patreon: / stevemould
Twitter: / moulds
Instagram: / stevemouldscience
Facebook: / stevemouldscience
Buy nerdy maths things: mathsgear.co.uk - Věda a technologie
hmm, that also explains why they don't spread jam on the tracks..
I love this comment haha
I've always wondered.
I wondered if he was gonna smear jam on his plate. But he got some boring powder instead.
Ew, that would get all mouldey
MaybeMisha , you stole my line! 😆
Expectation for test: a Model train set with little leaves - Reality: some guy with skates
Leaves in the lines
Falling so slow
Like fragile tiny shells
Drifting in the foam
@@capivara6094 🤗
@@capivara6094 what
I read this as "some guy with snakes"
Lol for real! 😂
- "Darling, what's the noise up here?"
- "Oh don't worry honey, I'm just jumping on a sheet of metal with ice skates on!"
"Alright, just be safe okay?"
"Yeah it's fine I haven't fallen yet, but next step is to make it super slippery"
@@WantEpicMusic - Just don't try to destroy the microwave again "
I feel like the lesson learnt here is that train announcers shouldn't say there's delay because of "leaves on the line", they should say something like that the "lines are dangerously slick". It's a bit newspeak-y sure, but it gets to the real problem better than "leaves on the line" because how many people know anything about the chemistry of crushed leaves on steel?
There's no need for danger (or as Steve put it, risk of crash). Stopping distance translates directly to time and therefore delays, as deceleration is needed earlier (and top speed may be reduced).
@@0LoneTech I think the fact that you have to slow down earlier means that the lines *are* "dangerously slick": if they weren't dangerously slick they wouldn't have to go slower.
It confuses me that people apparently don't seem to know that leaves on the tracks is a significant issue. It's well known to anyone with a driver's license that leaves on the road should be considered slippery conditions, and that's between rubber and asphalt, not two steel surfaces.
"poor breaking action due to cellular residue"
@@quenchize >"poor breaking action due to cellular residue"
>more reliable due to residual cell phones.
>left-over cell phones on a reliable mobile network.
>save up to 20% when you bring your old phone and switch to America's largest and most reliable 4G LTE network.
Where was I going with this? I don't know but applying brakes is called "braking."
As a train driver, I can definitely confirm that leaves on the line is a very real thing. The slipperiest condition for a train is lots of leaves and just a very slight drizzle.
Snow and ice, on the other hand, doesn't really cause slippery conditions at all. At least nothing like what you see on the roads. The problem with wintery weather has more to do with stuff like switches getting packed with snow, doors not closing, signs lamps getting covered with snow and many other things.
@@NodrapLego Where I work, my rail company does clear the track. Throughout autumn, we have trains cleaning the tracks with high pressure water jets. Much like snow plows on the road, they can't be everywhere at the same time, so it will get slippery again before the next pass, especially on very windy days.
@@NodrapLego Rail companies spend a vast majority of their income actually maintaining the tracks and stations that they control. If I remember correctly, a majority of rail company employees are actually all maintenance engineers, hired to be sent out to respond to damages to tracks and to maintain them so the trains can continue to run. Train lines need much more maintenance to continue to function than roads or even airport runways because cars are much more flexible at handling different weather conditions, concrete and asphalt are much more difficult to damage and runways are much smaller than the millions of miles of rail that covers almost every country.
As much as you can and will get delays, don't think that rail companies aren't trying. It's an extremely hard job to keep trains running throughout the year and they're doing all they can. After all, if the trains don't run, they don't make a profit.
Also, the amount of potential problems that plague rail lines compared to runways or roads is much, much larger. Roads only commonly need maintenance in two ways: repairing potholes and clearing snow in winter/applying grit salt. Runways only need the same two repairs with the addition of maintaining and repairing runway lights and ensuring the runway is as perfectly level as possible. Train lines, however, can flood, the rails can break, they can be sabotaged by thieves, lights can break, signs can be covered or damaged, switches can malfunction and break, there can be leaves on the track, ice on the track and so much more than I can't think of right now. I'm sure a train driver would be able to list more.
@A Google User what about if the leaves fall on a single line such as a branch line where the trains operate in both directions over the same track? Experience has taught me that is just as slippery!
IC used to have leaf blowers that ran up and down the line in the fall. (1970's etc)
Fun fact: Steam trains didn't suffer the "leaves on the line" problem, since they were so good at setting it on fire, foliage was kept to a minimum around the tracks/embankments, therefore, no leaves!
"So I ran those tests a few million times each..." 4:35 Almost didnt hear it lol!
Leaves on the line
Falling so slow
Like tiny fragile trains
driving themselves home.
Little conductor boy
riding to Rome
Brave conductor boy
Driving to Rome
Whelp, my purpose for clicking on this video had been satisfied.
If this is referencing General Iroh, I'll have you know, I didn't come here to feel T-T
😭😭😭
Uncle iroh. I cri for you.
@@Xylos144 Mine too...
Pedants' Sidebar: Even in North America, Jam and Jelly are not synonyms; jelly is either thickened juices or at least strained; whereas jam is actual fruit flesh, puréed and gelled, optionally with intact pieces.
Verified Purchase thank you. I was going to write the same thing
I did write something similar, but I wrote in American, not English! *:-)*
Thank you!
Yeah this is really important. I HATE jelly sandwiches, but I'm a huge fan of jam.
Most importantly, Jelly is thickened with Gelitin, whereas Jam is thickened with Pectin.
Hi Steve, speaking as a tram driver, I can SO relate to this because these days I live by it. Just a small correction point - when it rains steadily and the whole track is wet, that's my jam (pun intended), the friction is high and I can stop better than on a dry rail. But besides the leaves, the friction is also low when it's just drizzling, or the fog is settling down and the track is kind of wet but not really. We slide throughout the year, November is just extra sliding :D
Roads that have been dry for a while get slippery right when it starts raining, but less slippery after that first bit of rain. IIRC, it's something to do with oils or dust/tire particles that have collected on the road and haven't been washed off yet.
Yup, I agree. Steady rain means all the debris on the track is washed away. Drizzle + leaves is by far the slipperiest it ever gets for us.
Speaking as the Fat Controller, what are you doing watching CZcams videos? Get back to work immediately!
I honestly thought this video would be about people slipping onto subway tracks.
And the reason why modern trains have more problems than they did back in the steam and early diesel and electric days, at least in the UK, is a combination of there being less mass on each shaft on modern trains, and older trains used to have special steam jets and/or sand dispensers to improve traction and clean the rails that modern trains tend not to have. instead they rely on 'smarter' (read, "less harsh on the tracks") anti-slip brake systems, more cautious timetables, and the crushed souls of commuters
Another reason is that trees had to be kept well away from the tracks with steam engines because of the risk of fire. Since the abolition of steam, tree growth has been allowed. In fact, the lack of tree control has led to trees getting too close to overhead wires and causing problems with arcing.
@@johnhaines4163 Tree control also fell out of favor when someone calculated that it's cheaper to fix problems than employ tree control. Same goes with electricity companies.
I'm a train driver, and our modern trains still use sand. I've certainly used a lot of sand today. But you're probably right about the weight thing.
I don't know exactly where you live, but here in Germany even S Bahn (suburban trains) have sand. My city has a lot of overground routes surrounded by trees and yet I never heard this excuse
@@almerindaromeira8352 In Poland the earliest train is late at least 2 hours even in the perfect conditions so also we don't hear such announcments
When you think it's a physics problem but turns out to be more of a chemistry question.
WHO made all these physics rules we have to deal with?? 🤷🏻♂️
@@ludicrous7044 existence
physics and chemistry are heavily intertwined in most all real world applications. this is a physics problem that leads to a chemistry problem that leads back to a physics problem.
As well as increased stopping distance, another problem that can occur when breaking on slippery tracks is wheel flats.
If a train wheel slides against a rail, it will grind the metal of the wheel (because out of the 2, wheels are made of softer metal).
This grinding will create a flat section on the circumference of the wheel causing it to not run smoothly, which in turn can create extra vibrations which could damage even more of the train.
Yes. This was a big issue on the London Underground Piccadilly line following a storm in November 2016. (Despite the name much of London Underground runs above ground, and so can be vulnerable to leaves). Lots of trains were taken out of service at the same time for repairs.
Wouldn't the train have a system to not let the wheels slide, like anti-lock breaking?
@@userPrehistoricman Yeah, why doesn't ABS prevent this?
The important bit there is that even a very slight flat spot, if left untreated, will cause the mass of the train to move up and down with every revolution, and that a) gives the track a literal pounding and b)it causes the flat spot to get bigger.
@@MGSLurmey Because ABS is a reactive system, not a predictive system. ABS works by feathering the brakes when sensors detect that a wheel is decelerating more quickly than it should be able to. So in order for ABS to know that it has to let off the brakes, the wheel will already have been sliding for a fraction of a second. Which in the some cases can be enough to start a flat spot on the wheel.
You should also factor in that the crushed leaves on the rail make the surface not very smooth at all. So it's like riding on slippery sand paper. When a wheel does lock up the damage is done really quickly.
I can only imagine what his wife must have thought as he ran through the house fetching these materials.
A sheet of metal.
Ice skates.
Leaves.
Spray bottle.
Pectin.
Wife: What are you doing....
Steve: Science!
Wives of scientists and engineers are used to it.
People laugh until they step on leaves during rain.
Totally absolutely no reason why I'm mentioning this.
The road leaving the station, used by hundreds of commuters at once, all in a rush, is a deathtrap. Covered in leaves, worn down by foot, mixed with the rain overnight, and turned into this slippery shit for the next day. Too many times have I made an idiot of myself flailing around, trying to rebalance myself, on the way in to town.
As a driver myself, I know that leaves are a real problem. Although still bad, things are much better than 20 years ago thanks to intense treatment of the rails and on board train technology. The "Leaf Season" is still the most stressful time of year for a driver, as even the most experienced can get caught out. I also learnt alot from this video, as I knew nothing about pectin and the science of that.
Back on in the 1960's, I worked for W.A.Gov. Railways on the Mullewa - Meekathara line (Now closed). Our problems were with plagues of grasshoppers (locusts) that would bring trains to a standstill as all traction was lost. Sand on the rail helps a little. So as the climate changes don't be surprised at announcements that trains are delayed because of locusts or some other bug.
Where abouts is/was that line. Why was it closed? Would it be well used now if it was still open?
4:00 dude you can't leave your phone lying around like that, imagine stepping on it with the skates on
Steve, you should have also mentioned the interaction of leaf mulch with the signalling system. Insulation between the wheel rail interface causes trains to 'disappear' in track circuit areas!
Wet leaves also cause the opposite problem by completing the track circuit, creating phantom stationary trains in the signalling system that bring that section of track to a standstill.
I live in australia and ive never ever heard of a train delayed for leaves. Yes, we have trees here too
5 blades on your razor and you're still stubbled
Moist.
daveachuk too many boys these days have too many hormones that turn them limp wristed
I love that you can watch his stubble grow over the course of the video. Must have taken a few hours to film.
clean shaven is for 'insert insult here' ... I think that every time Jeremy Clarkson made fun of bearded men.
But let's all agree, mustaches are terrible; so be clean shaven, stubble, light to full beards ... but no mustaches. There is some George Carlin bit I don't remember well enough to paraphrase it; but it has something to do with people who are pensive/following rules that don't allow individuality ... like the military I think?
Morgan Harris Yeah. It took so long his shirt changed, too.
4:33 "so I ran those tests a few million times each" lmao
The 2021 Salisbury rail crash
is the perfect example of why leaves cause delays, a train with full emergency breaks demanded both by driver and TPWS still couldn't stop.
I read the title "leaves on the vine" at first and got Uncle Iroh feels
falling so slow..
*sobbing*
😭BRAAAAVE SOLDIER BOY COMES MARCHING HOOOOOOOOME 😭
I did too, and had to pause for a minute before watching the video to get back in the mood.
Me too bro. It hurts so deep.
Leaves on the line... train's running slow... like an unagile, grimey shell, wanting to go roam ... little conductor boy, let me go home... brave conductor boy... let me go hoooome
:Buys fancy pectin powder to simulate jam-like conditions:
:Ignores jam:
Acid and sugar are necessary for jam to be palatable, neither would be desirable in the demonstration using mild steel for which he had already identified a corrosion problem.
5:03 exactly 😄 🤣
Beautiful example of incremental perspective buildup. That's a mouthful. Familiar. Familiar plus. Familiar plus plus and so on... Leading up to the final ultimate simple test of measuring different levels of friction between the metal tray and the sheet metal.
The most amazing thing in this video is the remarkable ability of the human body to dynamically balance itself in real time. Watching even the best robots in the world trying to do the same thing really brings home how difficult it is.
A few million times, I feel like I smell a slight fib
Can you explain the railway condition of "couldn't find a driver"?
Usually means the driver who is booked to drive that train has been delayed elsewhere. There's not a huge cupboard of drivers and they just pull one out when a trains about to leave.
Thats called not bothering to turn up for work. i remember when some services were cancelled because there were no drivers available. i can't remember exactly when it was but i do remember that there was a big sporting event on at the time.
The UK railway is based on route knowledge - the signalling system tells the driver where they are going, but not how fast (which is the inverse of the continental system, where they tell you how fast, but not where)
This means that the driver needs to know the different routes they might travel down as to how fast they are able to safely travel. When a driver cannot be found, this means there isn't someone available with the correct route knowledge - either because of illness, or them travelling to that station on a service that is either delayed or cancelled. Given that the route a single service may take could be hundreds of miles long, it isn't practical for every driver to know every route
That's actually great! Thanks for explaining it, makes it a lot less annoying knowing that it's a good reason for delays
My best slide was in autumn 2000 when I decided to test the brakes at British Tissues Crossing on the Maesteg branch in a 158 at 50mph. The wheel slide prevention (sort of equivalent to ABS) immediately kicked in so I applied full brakes and let it do its thing. 2½ miles later, approaching Tondu, I was still doing 25mph. I did manage to stop at the platform, thankfully ;)
In the US jam and jelly are two different things. Jams tend to have pieces of fruit in them and they are have a lower viscosity than jelly. Jelly on the other hand is a lot like jello. It's viscous and sugary,and tends not to have fruit. I personally find jelly to be nasty.
Here in the UK it's roughly the same. Jam is less viscous, just thick enough to spread on toast and is usually fruit flavoured (artificially or naturally) but doesn't often contain pieces of the fruit itself. Jelly on the other hand is essentially exactly the same as Jello, only we don't have that brand here, all brands of Jello-like desserts (if it can even be called a dessert) are just called jelly.
I think it varies by where in the states you are, though. I've had American friends tell me that our Jam is called Jelly for them, whereas our Jelly is universally called Jello over there, despite what brand it is. Similar to how many vacuum cleaners in the UK are universally called Hoovers regardless of brand, same goes for Tupperware.
as a former hockey player, seeing skates being used like that causes me to cringe every time. growing up we were told never to walk with your skates on metal or wood since it would ruin them. i know it is a bit irrational since i saw you mention that you modified the blade in another comment but it is hard to shake off something that has been grilled into you. great video though
Michael on CZcams hahaha I just commented the same thing. I’m currently playing and officiating. Hurt my soul seeing skates treated this way. But I love Steve’s videos so it’s ok
@@ERobbo watching Cast Away must've really hurt for you guys then...
But it's in the name of science!
relax, steve is not using your skates
@@manus5423 i imagine they are some sort of dollar store variant :)
As a motorcycle rider I can feel these conductors' pain. Leaves are so slippery!
This is cool! I wondered about this as a kid when I would fish off a train bridge in the late fall. I haven’t thought of it for decades.
I’m a conductor in New York and leaves are the worst
How about kids? *:-)*
Leaves on the vine
Falling so slow
Man ever since I saw your collab video with Destin I'm in love with your videos they're awesome 🤩🤩 your dedication and curiosity blows my mind Everytime
Good demonstration! I am glad you did not get hurt
Jam =! Jelly
Jam has fruit pieces
Jelly has only juice
Marmalade is usually citrus and contains the peel
And Preserves are fruit chunks stored in jam
James Garrard Preserves are whole fruit If I recall correctly not just like part of the fruit
maybe in some cases but no, preserves are to jam what jam is to jelly.
Jam goes on toast
Jelly goes in a tub after dinner or with ice cream
In NZ jelly is what they serve in hospitals or as a dessert with ice cream jam can be with or without fruit pieces and goes on toast like peanutbutter and jam
“The chemistry of lubrication” mmm yeah Steve.
I don't know why but this is one of my favorite videos of yours.
I feel so lucky that I have found this channel. Thank you for these interesting videos.
Ah, thank you!
This may be a stupid question, but why not just put brushes on the front of all the trains, just in front of the wheels?
Brushes would have to be installed on every train which right now would be expensive but assuming you roll it out on all new trains there’s the problem of maintenance. Keeping the brushes clean on every train would be almost impossible however if you let them fill you could end up with leaves falling out of the brushes and the same problem happening. It would cause delays as trains would require more maintenance throughout the year vs delays during the main leaf season. Brushes could also could have a similar problem as they’re moving at the high speeds of trains. Though they are softer the speed of the train will still apply a great force to the leaves. They could still break and fall off the brushes. I’m no train expert though so take all of this with a grain of salt and probably wait for someone more qualified to give a better answer.
Did you see the consistency of the bonded pectins? Not sure how much a brush would help tbh.
@@ReegusReever They wouldn't become bonded pectins if the leaves are brushed off and not crushed in the first place. Prevention is better than cure.
I think you should call them and tell them you have the solution to their problem, they've probably not thought about it!
Or some kind of blade that scrapes off the rail, only used when pectin is likely to show up.
That has to be one of the worst experimental designs I've ever seen, so hats off to you for getting any data from it.
Brilliant and funny as always. Love it!
Steve, please don't rub your fingers across a razor blade. I cringed so hard after watching that.
Whilst I understand it's difficult, this is also something that happens **every** year. It's not like it's unexpected to have leaves in autumn, you'd think they'd be able to deal with it better by now.
In some parts of the world you get snow and ice every year. Even after clearing the roads and putting on better tyres, it's still slipperier than the rest of the year. We do similar things for our trains in the autumn, but much like on our roads, we can't just magically fix it completely.
But they do deal with it... by driving a little bit slower and warning people that there will be delays.
Thank you for running millions of trials to make sure we got the most scientific results possible!
My dad used to drive the trains and what you said totally fits. He also said that it's the inconsistancy of slippery and grippy parts so when you do brake on a slippery part suddenly the wheel gets grip again and it starts to flatten out. Which causes allot of sparks bumpy rides and replacing of wheels. Also like your videos!!
I'm so glad you waved the sheet of metal at the end. I always do that.
Every skater in the audience just cringed so hard watching you damage those runners
Oh, so this is why leaves are so damn slippery after a rain?
SentsuizanXS ...after a train, you mean? ;)
Ice skates have a concave blade surface, along with sharp edges, which cuts into the metal sheet. You must dull the skates first
Loving the old-style animations!
6:06 OMG CAN YOU NOT?!?!?! that made my whole body squirm watching you run your finger up and down that razor REEEEEEEEEEEEE
Now can you make a video where you come up with a solution to fix this issue so that you don't see puzzled faces anymore.
this video gave me goosebumps
That animation with sound effects at 1:22 is just perfect
I love your video but that test is ridiculous xD
Don't risk your life for an unreliable demonstration, we care about you ! Or at least make a clickbait thumbnail out of it !
The test at 8:40 is way more scientific, without being perfect of course and you could have talked about static friction and dynamic friction, you mesured the latter and it's the one we don't want for our train (wheels turning = static friction, wheels stopping and slipping = dynamic friction, which is always lower).
You could have explain that your measure need to be done at a steady speed with no acceleration, overall spend a bit more time on that experiment.
Well you just taught everyone how to derail a train.😁 Lay down some pectins/pectie (what ever the plural is) before a sharp curve or train station.
Uhhh, you know that's not how trains work, right?
I loOoOove this video ! The point is made in a very cool, may I call it ''lo-fi'' way. Hilarious AND educative. By the way, I've seen quite some of your videos and you are doing a great job. 👍🏻
Jam and Jelly are two different things. Jam is better, but we have both in America, though most prefer(or may not know better) jelly. Jelly is just juice mixed with sugar and pectins, where jam is made with the fruit pulp rather than just the juice. Jams spread and taste better in my opinion.
Did you take into account the fact that the skate blades have effectively two knife edges per blade when figuring out the relative pressure?
I rounded off those edges with a Dremel!
@@SteveMould Poor skates! But good job.
I'm surprised you didn't Mount to ice skate blades to a weight and then pull it with a rope attached to a scale so you could measure the amount of force it took to break the friction. Wouldn't that serve the same purpose?
Oh duh. Sorry I comment is halfway through the video
@@schelsullivan Top marks for coming back and owning your mistake! I was thinking the same thing too but had enough faith in Steve to hold out :o)
Yeah at first I was like what that's not the best way to do a home science experiment, but it is a sure-fire way to make a best CZcams video about a home science experiment and get your attention! And then bam real science
Love your channel. Thanks for the thoughtful and very palatable videos. But your place - has me intrigued as well. That big red pipe is generally a pipe for fire suppression water, here in N.A. Those beams as well. If this is your house, it must be super cool Please tell us more if possible.
The leaves on the line polymer formation is very similar to “seasoning” an iron skillet, pouring some oil on the pan and heating it at very high heat to bind the oil to the cast iron
Jelly is made just with fruit juice, no solids.
And? In the UK we call that Jam too, as well as Jam with "bits", they're both jam to us. Whilst to USA Jelly has no bits and Jam does.
No, jam with and without bits is referring to seeds, particularly raspberry jam.
The cherry seeds are the pits! *:-)*
> Jelly is made just with fruit juice, no solids.
Finished jelly does not contain "solids", but it is _made_ with solids (skins / seeds), to get extra pectin. It's just not made with _pulp._
> And? In the UK we call that Jam too, as well as Jam with "bits"
No, jam (whether with or without bits) is made from fruit pulp.
"And? In the UK we call that Jam too, as well as Jam with "bits", they're both jam to us. "
-This isn't really true. Or shouldn't be any way. Baxters redcurrent Jelly is the real deal
1:52 Hmm, for some reason I am reminded of a Mythbusters episode where they ended up concluding that in order for one of their small scale models to be accurate they would have needed to use a doll made of enriched uranium. I wonder why?
I don't know about that episode, but if everything was to scale and made of the same materials, the mass would be proportionally much lower. A cube at 1/2 scale would be 1/4 the mass.
For a given train you can calculate the contact area and then the pressure on each wheel, and then figure out how narrow the blades need to be to achieve the same pressure from a human.
@@james0xaf I was actually wondering why I was reminded of that particular episode, mainly because I haven't seen a Mythbusters episode in over a decade. Long term memory is such a wonderful thing.
Major problem with scaling is that gravity can't be scaled down.
They wanted a radiating video! *:-)*
You sure they didn't say "depleted uranium"? It's a safe version of uranium used in applications that require very heavy/dense/strong material.
Once I was traveling on the west-coast mainline and there was a delay due to sheep on the line.
binface9
Sounds like Wales
I've never heard of leaves on the line being a problem in the Netherlands. I think it's because the train lines (at least near my part) are raised almost everywhere and the trees near the tracks have been removed.
I wouldn’t mind Steve mould lubricating my track.
wow steve are you cosplaying as tom scott
My car (RWD and manual) once lost traction on wet leaves and a slight bump as I entered a sharp corner. Luckily I was quick to respond and natural intuition kicked in. I saved myself, the car, my passenger and oncoming traffic with split seconds left.
If I hesitated, it would have most likely been a major incident.
My childish days of reckless driving had saved my life by teaching me how to regain control of a vehicle.
They didn't use to have this issue in the days of steam, for two reasons:
1. They cut down vegetation next to the line, so that it didn't catch fire.
2. They used sand (often steam blasted) to put sand on the track to improve adhesion.
The only mostly steam railway, (The Romney, Hythe and Dimchurch) doesn't have issues like this.
This would be more convincing if not for the fact that trains still run on time in Japan, a country with an abundance of leaves. Perhaps because they spend more time, effort and money on railway maintenence than Southeastern? (And less on sponsored videos to explain away their failures.)
Boom
Maybe clear all trees closer than 20m. Can't imagine any real amount of leaves getting on the track then, unless it's located in some kind of lowland
Leaves don't exactly effect maglev trains
@@MushookieMan True, but that's a long way away from being a significant portion of rail in any country. There's exactly one operational maglev system in Japan, and it's a tiny one.
I wonder if it's a combination of type of tree, vegetation management, and having separated rail (rail bridges?) I don't remember rail in Japan being too close to forested areas, but I definitely see that in Britain
I noticed you seemed to be using green leaves not the dead, crumbly brown ones that land on the tracks in fall. I can't say exactly why, but I really do think that would make a big difference.
I suspect the fall leaves may have more pectin and I am reasonably certain they break down, release pectin and stick to the tracks much more readily.
Source: I spend a lot of time cleaning up stacks of leaves that arrive inside my front door on the soles of my family member's shoes. They stick together quite firmly and are slimy when wet. That doesn't happen with leaves in the summer. This is true even when we spend entire days pruning trees and walking on leaves.
When it comes to railcars it is about maintaining the adhesion of wheel to rail. Leaves on the rails reduces this adhesion, even before the chemical reaction (Jam). The second part of your experiment (pulling the blocks on the pan) would've been a sufficient explanation. It is the same as driving you vehicle over wet leaves on the road. Try pulling the blocks on the plate with just wet leaves. The friction will be even less.
6:55 Creating that thin layer of Bondage xD
Really interesting! I'd not realised there was chemistry at play in leaves, I thought it would just be they slid underneath!
Watching on the train from London to Glasgow
Congrats on relevant sponsorship
I rode Amtrak from Buffalo NY to Rhincliff NY, in the middle of the night. Between Albany and Rhincliff there's a section with water on both sides. We were doing 65mph through there with confirmed tornado touch downs in the area. Any other place wouldn't bother, except maybe a tall bridge or cliff, but surrounded by water is kinda scary.
In the not so distant past there was a SPAD incident near Stonegate. A train ran without the Driver being able to bring the train to a stand for some miles due to leaf mulch on the tracks.
This is one of those crazy phenomena that kind of only happens by chance since we happened to come up with this specific mode of travel, but also happens to be EXTREMELY DANGEROUS to TONS of people and really IMPORTANT TO UNDERSTAND.
There are also issues relating to signaling that will lead to further delays on top of defensive driving from the train drivers. If a rail becomes covered enough or the wheels on the train become contaminated enough, you also have a risk emerge of the trains failing to correctly show up on the track circuits as the build up insulates the train (Not an issue on axel counter areas). This presents the potential of creating a situation in which two trains could end up in one section or other issues relating to incorrect track activation. In response there is often double blocking introduced, or working by telephone between signal boxes to decrease the potential of accidents.
Actually a train not stopping on time is not the real problem as you might think. They tend not to stop that fast anyway. It's that slipping creates flat spots on the wheels, which in turn ruin the rails. That is quite costly and time consuming to repair as you might imagine.
Smarter everyday did a video on ice skates.The blades aren't flat, most have two blade edges on the outside so it forms an upside down V on the ice like ^. It might affect Steve's testing and calculations on the similar static pressure exerted on the metal plate.
It's a big oof from me, an train driver in Germany. I can totally relate to that!! When you're experienced in driving trains, then you drive respectively with your gut feeling.. and this feeling definitely changes during autumn. It happens automatically because the feeling you get, braking on the slippery tracks is immensely different... Yes, we have an antiskid system, but that elongates the stopping distance even further (primarily to reduce damage resulting of blocking wheels). The real tool to deal with this kind of problem, is to apply sand right in front of the wheels to increase friction. It works wonders to shorten the stopping distance in these conditions.. for a measure, I'm adding 50% to the stopping distance, to safely stop the train at any given moment. That's roughly accurate and based by experience only, but never the less, therefore I can stop a train within a few centimeters in precision, at any given moment...
Concord, Jam, Jelly and so on are names for seeds-in, sugar cooked or sugar-added and so on. They're different, we use it the same as you do in the USA.
I worked for a north American rail lubrication company and we teamed up with a company in the UK. They use a product with sand inside which helps to grind off the pectin and "leaves on the line".
Love it!
I would have never imagined!
Also a problem in my city for cars depending on conditions. I switched to snow tires early this year (end of October) for that reason. So they are not yet snow tires but leaf tires. I normally wait until mid-November. I ride my bike to work daily so it's the same problem there as well until I get off the side streets near my home where the leaves are several inches thick, nicely mashed by traffic, but not yet cleared.
This is hilarious
Love you steve
Know that I'm years late here, but you could have named this video "giving my viewers crippling anxiety over trying to make myself slip in a closed room with ice-skating shoes" and it would have been completely adequate regardless of the whole situation. All jokes aside, lovely video Steve, glad I'm finally getting to binge all your content after having it on standby for literal years now. Cheers!
This is pretty nice, inspiration on how to do science yourself
Hello Steve, I'm an italian train driver.
I prefer heavy rain than humidity by fog or drizzle, I have more adherence problems in the second case.
Another strange situation is when sea water droplets go on the tracks, slipping problems again.
8:33 "To give this video some semblance of scientific rigour"
This part with the cinder blocks would have been enough on it's own, but not even nearly as entertaining.
You know what you are doing, please carry on! We love you, Steve!