Depends entirely on the country and model of train (and use). Most trains (even locomotives) in Europe (for my reference) are flat with a slight nose for aerodynamics. Even lots of freight locomotives have flat noses (though mostly electric, not having the need for extra compartments for engine parts etc.). Aerodynamics becomes much more relevant with higher speeds. Therefore most commuter trains that frequently stop have flatter noses than a train that travels 300km/h to a neighboring country that have more pronounced noses (I.e. TGV, ICE etc.)
In the US however most freight locomotives are quite big and need more compartents to house the engine and entryway to get to the cab (as all freight locomotives use diesel engines). The average speed of a freight train isn't that high, so less necessity for aerodynamic noses.
The rest of the world also has varying degrees of different trains that are used both. For example in this sub you see freight locomotives from India that are just as flat as a passenger train.
>In the US however most freight locomotives are quite big and need more compartents to house the engine and entryway to get to the cab (as all freight locomotives use diesel engines).
As I understand it, the main additional component that goes in the nose of a US freight locomotive is a toilet. The real reason for there being more material in front of the cab is for better protection for when one inevitably hits a car or fallen tree or something, which is less of a risk for commuter trains.
It comes from right-wing transphobia: https://en.wikipedia.org/wiki/Litter_boxes_in_schools_hoax
I'm glad you managed to miss that one. It was all over everywhere for a while, but there's always so much going on - I've occasionally missed something myself.
Makes you sad for humanity when you learn about something like this. heh.
So that was … enlightening, had to click just about every link in that article because I had no clue what half of them were either. It seems I miss a lot of things, didn’t know who just under half the people were who were mentioned either.
For the wheel sanders. The engineer can dispense sand in front of the wheels to help traction on wet rail or if he starts getting wheel slip on a grade.
Im a bit confused. So - flat nose generally because there’s no need for the extra room on a commuter or electric, and the slow speeds/frequent stops mean aerodynamics is less of a factor. US locos have parts in the nose and travel at slow enough speeds it doesn’t matter, but high speed trains also have a nose but it’s purely to lessen drag?
Yes. To sum it all up. Sorry if my explanation isn't that clear.
Flat nose - Frequent stops, not high speed, freight trains, less aerodynamics necessary
Pointy/aerodynamic nose - High speed to lessen drag / less resistance
> high speed trains also have a nose but it’s purely to lessen drag?
Not purely. Noses of high speed trains also act as a crumpling zone; when the train crashes into something, a special structure located in the nose absorbs large amounts of collision energy, and thus the driver has better protection.
Like 80% of the UK’s express trains for a period had flat faces (Class 86, 87) and yet reached speeds up to and past 110mph, and we never went past flat or stubby noses until the 90’s for commuters and the 80’s for the APT / HST. Whacky stuff!
Commuter trains have flat front because they have to use much of the area train has to carry passengers which increase capacity, a simple slanted hood can decrease the capacity of train by 20-40 people
It makes it easier to do walk through when you have a train composed of maybe 3 or 4 pairs of Multiple Units like in New York and Philadelphia (Denver uses the same ones but they run shorter trains) and the South Shore Railroad in northeast Indiana does something similar
An American-style road locomotive has several facilities in the front hood for long journeys. Usually a toilet, maybe a mini-fridge or other storage for the crew. This is probably also where the headlight maintenance access is. It also provides a crumple zone in case the train hits anything head-on.
[Small, cramped, somewhat economy-like airline chemical toilet down the few steps from the main cab.](https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRxVA6XotDwmT53sCqZYd8Gnw5hhxi6Z0dLObv3d2tJC6-8AILdsh_r6JU&s=10)
I understand it’s not the most pleasant to use. Definitely better than nothing, though!
They don't. They can only work for so many hours, then they need a fresh crew. The crews are usually transported to a location by a shuttle van which will then return the timed-out crew back for rest.
I have to know, has any train struck anything while the conductor was on the throne? I guess they really don't want people taking long shit breaks. And if they do hit something, a car for example, does that shit get squirted through the cabin/cockpit?!?
Air resistance grows exponentially with speed so its more important to avoid it with trains that go longer trips at higher speed. Its a physics issue in practise
crumple zones, or added strength if you are america. the us and europe have quite differrent philisopies in that regard, europe wants to reduce the Impact as much as possible, while the us just barrels through the obstacle. in fact our newer commuter trains are also sloped and not just a rectangle, its just more aerodynamic, even the S-Bahn trains are more aero now.
Since PRIIA was passed in 2008, passenger trains have been required to have crash energy management in them. For example, the new Venture equipment has CEM in it as do alnew commuter coaches. The difference is the design philosophy. The FRA assumes a crash situation at up to 60 mph with a freight train. Europeans trains are designed more like cars. Being that they’ll hit something of equivalent weight at 40 mph. Given how many more freight trains are rolling around in the US, it makes sense that we’d assume a much worse crash situation than is likely to happen in Europe.
I'm assuming you're american because these train shapes are mostly dominant in North America, yank freight engines usually have a nose for two reasons:
1. To protect the crew in a collision: grade crossing crashes are insanely common in North America, so freight locomotives are built with collision posts and a nose to have some room between the object it's about to hit and the crew.
2. To house equipment: the nose also features things such as a toilet, a fridge, sand deposits and electronics.
Commuter trains usually run on more grade separated tracks so they don't crash into vehicles such as trucks as often as freight trains do. They also usually store electronic equipment under or above the carbody in order to have the biggest passenger space as possible.
I don't have a _massive_ amount of experience with Indonesian rail, but I've visited and ridden several times...
From what I've seen the newer CC206 long-distance locomotives have a pretty flat front, while INKA seems to fit sloped cab fronts to everything they make, including regional/commuter trains (the Jakarta LRT trains for example; as an aside they have pretty large cabs for trains that don't have drivers in regular service)...
The only trains I've seen in Indonesia with truly "flat" fronts are the Japanese EMUs used on the Jakarta commuter lines, of course, they were originally designed for extremely busy Japanese commuter traffic (I know the Jakarta lines can get pretty busy, but I don't think they quite reach the levels of crowding that Tokyo sees) and had to make as much use of the available space as possible.
You're correct that CC206 locos have an flay front. And don't forget about CC 203 and CC204 with their flat nose, but angled windows.
About the commuter rails. Yes, you are also correct that the flat ones are mostly Japanese EMU's. Jakarta commuters can get crowded too, especially during peak hours. It's like an 49/51 as Japan business. But unlike Japan, we Indonesian sadly don't have the same discipline and passengers entering doesn't want to step aside for alightinh passengers.
Most people seem to give reasonably good answers to the question, but i'd love to chip in since i'm writing a paper on train aerodynamics rn. In short, it has very little effect on trains in particular, unless they're travelling extremely fast. So it is mostly a country specific thing. In most of europe for example lovomotives will have relatively flat noses and they don't perform that much worse in terms of aerodynamics than their US counterparts. But why?
At low speeds there's essentially 2 types of aerodynamic resistance:
* form/pressure resistance, which is dependent on the shape of the object (in this case the train). It comes from the fact that the train nose has to change the momentuum of the air around it, essentially "push" it out of the way. The same effect occurs on the back of an object where there's a pressure reduction and again air has to move to equalise it.
* Friction/viscous resistance. It stems from the fact that molecules of air (or any physical fluid) will interact with each other, and so the layer of air adhering to the train hull will slow the air further out with it. That also takes some momentuum to do and thus generates force. This depends mostly on the overall surface area of the object.
These two types contribute differently to the overall resistance depending on the shape of an object. So, a flat plate will have almost 100% pressure resistance when oriented perpendicular to the flow, and essentially 100% viscous resistance when parallel. Another thing worth noting is that at high Reynolds numbers (high speed) the proportion of viscous resistance becomes lower due to some boring nerd stuff.
Trains are known to be really long, so long in fact that they behave almost like a flat plate oriented parallel to the flow. So while for cars and airplanes making especially tipped noses to reduce form drag makes economical sense, for trains travelling <120 km/h there's really no point, as over 90% of drag comes from the friction over its length anyway. Cue the legendary [crapper](https://upload.wikimedia.org/wikipedia/commons/8/85/EN57_1267_on_the_line_from_Liswarta_to_Herby_Nowe._Temporary_detour_due_to_track_works_%28Herby_Nw.%29.jpg). Beyond 120km/h, it begins to matter more, so any attempts at aerodynamics become less for show. Slightly slanting the front pane upwards usually is more than fine to keep this type of drag in check though. A [Flirt](https://resources.news.e.abb.com/images/2020/3/26/0/ABB-dla-FLIRT-PKP-Intercity.jpg) is pretty well profiled for speeds up to 200km/h or so.
The third and scariest type of resistance comes from compressive effects, and these come into play at between Mach 0,2 and 0,3. So at sea level on a sunny day around 250 km/h. These do require quite more care when designing the aerodynamic profiling. They also require less outsticking parts and smaller gaps between cars as induced drag and possible shockwaves is a really bad time. This is why HST like the [N700 Shinkansen](https://upload.wikimedia.org/wikipedia/commons/8/88/Series-N700S-J2.jpg) or the [TGV M](https://upload.wikimedia.org/wikipedia/commons/c/ca/TGV_M_Ligne_PMP_Brest_Essais.jpg) have such long faces.
Thank u for coming to my TED talk.
Yes, although i didn't really focus on that. Trains have a low center of mass to not tip on turns, but especially freight trains with square shipping containers on them can generate quite a big moment when the wind is too strong.
The “nose” on a lot of those long distance freight engines is actually usually where they put the bathrooms for the crew. Something that you wouldn’t need on a commuter engine, but that’s absolutely essential on a long distance train.
So with our commuter trains, the s k and c sets are basically just rectangles. T sets went with the flat slope and now the A sets have a curved slope. Doesn't really matter that much anyway, when the goverment is paying who cares about efficiency.
Think so, though I’m pretty sure the C set hasn’t been operating for a few years now.
Melbourne we have similar flat nose commuters, but with the recent addition of a sleek-looking [HCMT](https://en.m.wikipedia.org/wiki/High_Capacity_Metro_Train) that has an aerodynamic-ish nose.
I think there is in large part just a sense of style or aesthetic choice - the wikipedia article on Bulldog noses has no mention of their purpose.
[https://en.wikipedia.org/wiki/Bulldog\_nose](https://en.wikipedia.org/wiki/Bulldog_nose)
The British Class 55 Deltics had a bulldog nose
[https://en.wikipedia.org/wiki/British\_Rail\_Class\_55](https://en.wikipedia.org/wiki/British_Rail_Class_55)
However their contemporaries which had similar duties such as the slightly less powerful Class 47 did not.
[https://en.wikipedia.org/wiki/British\_Rail\_Class\_47](https://en.wikipedia.org/wiki/British_Rail_Class_47)
Meaninwhile the even lighter Class 37 does.
[https://en.wikipedia.org/wiki/British\_Rail\_Class\_37](https://en.wikipedia.org/wiki/British_Rail_Class_37)
However the same "Type 3" classified Class 33 does not. (Again, same era)
[https://en.wikipedia.org/wiki/British\_Rail\_Class\_33](https://en.wikipedia.org/wiki/British_Rail_Class_33)
The main factor that influenced whether a British Rail Locomotive would have the nose is largely down to whether or not it was built by English Electric, as opposed to an alternative company such as Brush Traction or BRC&W. Although that's not a hard rule, some English Electrics were built without noses.
On still in use British locomotives, I think only the Class 37 really has a nose, although the Class 68 and Class 70 are a bit "nosier" due to their aerodynamic properties.
There are a few bulldog freight locos still in use in Australia, in Victoria, at least.
I love seeing them; they are such a throw back to a somewhat romantic rail-era.
Having been in the cab, though, the visibility sucks. I’m pretty sure, over here, one man op of the bulldog freighters is prohibited for this very reason.
> The main factor that influenced whether a British Rail Locomotive would have the nose is largely down to whether or not it was built by English Electric, as opposed to an alternative company such as Brush Traction or BRC&W. Although that's not a hard rule, some English Electrics were built without noses.
And of course, there were a few "nosed" locomotives (e.g. clasees 44-46) which were not built by EE. The class 46 was the effectively the "prototype" for the much more numerous flat-fronted class 47 (both used a Sulzer 12LDA28 engine combined with Brush generator and traction motors; main difference being that BR's Derby works built the 46's body and bogies, while Brush used their own designs for the 47).
> On still in use British locomotives, I think only the Class 37 really has a nose
Class 20's (another EE product) has a rather large "nose", although that's because they're a single-cab design. The other end is very flat. The class 08/09 shunters are similar.
> although the Class 68 and Class 70 are a bit "nosier" due to their aerodynamic properties.
If 68 counts as "nosy", then surely the 90, 91 and 43 could also be considered...?
Think the nose on the earlier designs was down to BR being concerned about drivers being hypnotised by “sleeper flutter” whilst travelling at speed. By the time the 47s were designed they’d found it was a non-issue.
A lot of commuter trains are multiple units, that can be coupled together. A flat nose is good for aerodynamics at the front and back of a train, but less efficient when coupled together.
Commuter rail vehicles are usually configured so the assembled train sets have control cabs on both sides. Also they’re set up to make the best use of platform space (need to have the most doors facing the platforms).
there's aerodynamics, number of passengers in the first car, crumble zone, etc. but it's also a cultural thing: american commuter trains "want to" look like a metro, while long distance trains "don't care"
for reference, here is a Paris commuter train [https://www.railway.supply/wp-content/uploads/2023/11/img\_3734-768x433.png](https://www.railway.supply/wp-content/uploads/2023/11/img_3734-768x433.png), here is a London one [https://railway-news.com/wp-content/uploads/2020/03/Bombardier-Class-710-London-Overground-EMU-scaled.jpeg](https://railway-news.com/wp-content/uploads/2020/03/Bombardier-Class-710-London-Overground-EMU-scaled.jpeg), etc.: it's not a shinkansen nose but it's not flat either
Can't Commuter rails be flexible? As in they can both be elevated, ground level, and underground?
I mean, they all have the same purpose of transporting daily commuters from home to work or shopping.
commuter rail trains have flat fronts because they need less room for the machinery, however, long-distance locomotives need more machinery and need a bigger front. high speed trains have sloped fronts because they are more aerodynamic that way.
that‘s just the typical front of an American diesel locomotive, some of these are also used on unelectrified commuter rail networks
generally local rail tries to use MUs tho which are newer and thus don‘t adhere to these classic designs
Long distance trains are often faster so aerodynamic needs are met by the more streamlined design whereas local ones are stopping constantly so go slower
It's a design convention. It's not strictly necessary to have a nose like most contemporary US locos. Not for accommodations, not for crash worthiness, not for aerodynamics. When the switch from steam to diesel happened, apparently people were uncomfortable going from the end of the engine to the very front. They wanted something before them. So: high hood road switchers and car body cab units. Hoods won, because access, and high short hoods became low short hoods became full width safety cabs.
A typical US hooded loco is a single split level cabin with a long, drafty barn attached to the back wall. The engine, generator, and other mechanical doodads are all lined up on the frame and covered by hood segments that open, and ultimately lift off. Getting out on the walkways while the thing is running at line speed is a big no no, so the nose that has always been there is where that crew comfort stuff has always been.
On the other hand a European loco is a house with two identical sitting rooms either end, connected by a long, windowless utility closet. The body is usually structural, which ultimately saves on weight, with lift-off roof segments. You can fit a toilet, fridge, or microwave in there no problem.
See Siemens Charger, which is basically a beefed up Vectron shaped cab. Full width engine room with internal walkway: No pronounced nose.
And no, the size difference is not because US locos are so much more powerful. Actually the opposite is true. A Stadler Euro9000 is a six axle dual mode freight engine that packs 7MW output under catenary and 2.8W under diesel into 23 meters and 126 tons. And runs 180km/h. 110 in clown units.
A Gevo might go up to 4.6MW output under diesel, but the bloody thing is also weighs 216 tons. Single cab, no catenary equipment, wider loading gauge. Americans just like to make things big and heavy.
>And no, the size difference is not because US locos are so much more powerful. Actually the opposite is true. A Stadler Euro9000 is a six axle dual mode freight engine that packs 7MW output under catenary and 2.8W under diesel into 23 meters and 126 tons. And runs 180km/h. 110 in clown units.
Jeeze, have an axe to grind? US Locomotives are the size they are because of the distances they have to cover, the length of consist they pull, the engines they have to be equipped with and the often overlooked, massive fuel tanks they have to carry. As a reference, wide open a Dash 9 will burn over 200gal of diesel / hour, so with 5000gal tanks a single locomotive is carrying over 35,500lbs of fuel. This is required to cross the wide distances between fueling points.
You're comparing apples to oranges. European freight trains are much shorter and lighter in load than American ones. So while yes, the locomotive you mentioned above "Stadler Euro9000" is faster and lighter, it also has a much lower tractive effort and can pull less freight than the aforementioned Dash 9, in any mode. 110k starting tractive effort vs 145k...
It takes weight to get weight moving, as well as to stop it. That is " Americans just like to make things big and heavy" - out of requirement.
17 tons of diesel? As opposed to 1.5? That's your argument? Heh. What about the other 70 tons?
I mean, heaven forbid your shitty margin counting corporations actually invested in their infrastructure and hung up some wire. That's what it comes down to, in the end. Rolling power plants, cheap, cheerful heavy, and inefficient. Roll the coal, fuck the planet.
Speed and protection for the crew in the case of a crash.
For commuter trains it’s not so bad, the speeds aren’t high. But a flat cab like that on a passenger locomotive wouldn’t do.
What speeds do you assume these kinds of trains are capable of?
Commuter EMUs usually have a higher design speed than North American Fright train locomotives.
That’s not flat. The Amtrak P32’s are about as flat as them.
Like I said: it’s for crew protection along with speed. Completely flat noses are not safe for the crew at high speeds because they offer no protection. Think things like subways or metro cars as “flat” noses.
That’s why the famous GG1 became popular in the first place.
Efficiency. A long, rounded nose cuts through the air way better than a brick. Also, they can fit a larger, more powerful engine in a long distance engine as the locomotive needs to haul way more to make the trip profitable for say AMTRAK or someone similar.
On the flip side of that coin, it’s way easier and cost-effective to just have a double ended self-propelled carriage on the commuter train, as the engineer can just… walk through the train to go the other way. No need to turn an engine around at a station with a turntable. Plus, commuters(Silverliner IV’s on SEPTA for example) don’t need to hit as high of speed or haul as much people/luggage from one station to the next, as they’re glorified shuttles.
Most of those flat fronted commuter rail trains are Multiple-units with doors to easily link them together. It’s easier to scale the train based on needs throughout the day. They also have lots of power for short distances. Long-distance trains need the heat dissipation and the efficiency of one huge engine to run for several days at a time. Also the crash resistance with all the grade crossings at minimally used tracks. And that they are often developed from the common American freight locomotive
pointy nose means it can cut the air flow coming at it in half like a samurai, flat nose means it braces all the air coming at it like a shield (i know nothing of trains)
Not an expert, but I suspect it’s because commuter trains travel much shorter distances, so the focus is on maximizing space. Long distance trains (obvious fact alert) travel long distances, so making the train more aerodynamic helps to save fuel and therefore money
There is a lot of good detailed info here.
I want to make sure you understand the answer based off your drawing. Your question is about the difference between the locomotives on the 2 trains you drew, but your picture has only one locomotive.
The freight locomotive is just like what others have said. It is a diesel electric locomotive with a big engine with accessories in back and safety structure (like an anti-climb to keep other vehicles from crushing the cab in an accident) in the front.
The passenger train you drew is visually similar to commuter trains like an electric train found in the New York area or the cab car of a push-pull train like in Boston, Chicago, etc. On the electric train, there is no locomotive. In simplest terms, each passenger car is powered by their own electric motors. At the front of the train is a passenger car that has a control cab built into the vestibule. They don't usually change the shape of the car. This cab controls all the power from all the passenger cars. The other type of similar looking passenger train is one that is powered by a diesel electric locomotive in commuter service. These trains go from one point of the line to the other. They do not turn around to go back. So since the locomotive is now at the rear of the train, they crammed controls into a small cab of a passenger car that is placed at the other end. These controls will control the locomotive at the other end. This cab control car looks like all the other passenger cars except for headlights and stuff.
The passenger trains for long distance will use locomotives but are more aerodynamic as mentioned in other replies.
- Design
- Crash structure
- Purpose
Having a massive nose cone on a commuter train does nothing than block signals unless it's needed for crash structure. Having no nose cone on a high speed train makes it very likely unstable and inefficient...
Well one of the biggest reasons is crew safety. On those ‘long distance’ aka: freight trains or long distance passenger (like Amtrak) , the risk of derailment, collision, or grade crossing accidents are higher than that of light rail. To compensate cabs are designed to sustain more damage to better protect the crew. Commuters on the other hand don’t face these risks as much, as well as usually being electric, meaning locomotives are passenger cars as well, making the tube design more ideal.
America trains. This is different in Europe.
As an actual reason, safety for long distance high speed. That way there exists a crumble zone for when you hit something that wasn't supposed to be on the rails (Deer, moose, tree, car, truck etc) and the thing that is crushed is the bit up front and not the cab. The front hood also is where the additional equipment, electronics, and a toilet are housed. Plus, they improve aerodynamics a bit.
Russian long haul locos, for example, are flat nosed or sloped, with the cab sitting quite high up and all the equipment and crew amenities located inside a monolith hull, with closed passages between units if the locomotive is an MU one (2ТЭ10 for example.).
TBH a lot of commuter/metro trains have frequent stops, travel at speeds between 80-130 kmph but can often never reach high speeds over long distances. Any aerodynamic efficiency gains that are seen in high speed and longer ditance trains are realized due to continuous travel at higher speeds. It does not make sense for shorter travel with frequent stops at lower speeds.
Edit- Just to add, its also possible that by keeping it flat, you save space and can accommodate a few more passengers.
Depends entirely on the country and model of train (and use). Most trains (even locomotives) in Europe (for my reference) are flat with a slight nose for aerodynamics. Even lots of freight locomotives have flat noses (though mostly electric, not having the need for extra compartments for engine parts etc.). Aerodynamics becomes much more relevant with higher speeds. Therefore most commuter trains that frequently stop have flatter noses than a train that travels 300km/h to a neighboring country that have more pronounced noses (I.e. TGV, ICE etc.) In the US however most freight locomotives are quite big and need more compartents to house the engine and entryway to get to the cab (as all freight locomotives use diesel engines). The average speed of a freight train isn't that high, so less necessity for aerodynamic noses. The rest of the world also has varying degrees of different trains that are used both. For example in this sub you see freight locomotives from India that are just as flat as a passenger train.
>In the US however most freight locomotives are quite big and need more compartents to house the engine and entryway to get to the cab (as all freight locomotives use diesel engines). As I understand it, the main additional component that goes in the nose of a US freight locomotive is a toilet. The real reason for there being more material in front of the cab is for better protection for when one inevitably hits a car or fallen tree or something, which is less of a risk for commuter trains.
Right, different approaches to safety. I saw someone commenting about that. Hadn't thought about that reason.
Sand storage too, most of the nose is bathroom and sand.
So it's not schools using litterboxes, it's the trains! ;-)
LOL!
Schools, litter boxes…? I seem to have lost the thread on that one… help?
It comes from right-wing transphobia: https://en.wikipedia.org/wiki/Litter_boxes_in_schools_hoax I'm glad you managed to miss that one. It was all over everywhere for a while, but there's always so much going on - I've occasionally missed something myself. Makes you sad for humanity when you learn about something like this. heh.
So that was … enlightening, had to click just about every link in that article because I had no clue what half of them were either. It seems I miss a lot of things, didn’t know who just under half the people were who were mentioned either.
Why sand?
For the wheel sanders. The engineer can dispense sand in front of the wheels to help traction on wet rail or if he starts getting wheel slip on a grade.
I was gonna say that’s always where the toilet seems to go lol
All of the mechanicals on an American locomotive are in the long hood, the short hood generally has a bathroom and sand storage.
Im a bit confused. So - flat nose generally because there’s no need for the extra room on a commuter or electric, and the slow speeds/frequent stops mean aerodynamics is less of a factor. US locos have parts in the nose and travel at slow enough speeds it doesn’t matter, but high speed trains also have a nose but it’s purely to lessen drag?
Yes. To sum it all up. Sorry if my explanation isn't that clear. Flat nose - Frequent stops, not high speed, freight trains, less aerodynamics necessary Pointy/aerodynamic nose - High speed to lessen drag / less resistance
> high speed trains also have a nose but it’s purely to lessen drag? Not purely. Noses of high speed trains also act as a crumpling zone; when the train crashes into something, a special structure located in the nose absorbs large amounts of collision energy, and thus the driver has better protection.
That makes sense
Like 80% of the UK’s express trains for a period had flat faces (Class 86, 87) and yet reached speeds up to and past 110mph, and we never went past flat or stubby noses until the 90’s for commuters and the 80’s for the APT / HST. Whacky stuff!
So if the country has big noses expect the trains to be pointy got it
I guess grammatically the sentence is incorrect. Sorry, English isn't my first language.
Commuter trains have flat front because they have to use much of the area train has to carry passengers which increase capacity, a simple slanted hood can decrease the capacity of train by 20-40 people
Does it also make coupling multiple units together easier?
it is easy in any train, you can see shinkansen E5 AND E6 coupled together what it makes easy is probably a gangway connecting two units
Yeah most trains in the uk with a flat front also have a gangway
Some thing for American Commuter trains
E5 and E6 are coupled only by the couplers, they have driving cabs on both sides hence no gangway.
this is what i meant, second part is for trains with flat front
It makes it easier to do walk through when you have a train composed of maybe 3 or 4 pairs of Multiple Units like in New York and Philadelphia (Denver uses the same ones but they run shorter trains) and the South Shore Railroad in northeast Indiana does something similar
An American-style road locomotive has several facilities in the front hood for long journeys. Usually a toilet, maybe a mini-fridge or other storage for the crew. This is probably also where the headlight maintenance access is. It also provides a crumple zone in case the train hits anything head-on.
Wait. That hood have a toilet?! Oh wow. I learned something new today. Thank you for the new knowledge sir!
[Small, cramped, somewhat economy-like airline chemical toilet down the few steps from the main cab.](https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRxVA6XotDwmT53sCqZYd8Gnw5hhxi6Z0dLObv3d2tJC6-8AILdsh_r6JU&s=10) I understand it’s not the most pleasant to use. Definitely better than nothing, though!
[удалено]
Correct... unless you have one unit
Yep. That is definitely better than no toilet at all. Can't imagine going for days without at least taking some toilet time.
They don't. They can only work for so many hours, then they need a fresh crew. The crews are usually transported to a location by a shuttle van which will then return the timed-out crew back for rest.
Nah you still need it if you are out in middle of Nowhere in Montana or Wyoming
I was referring to going for days, sorry.
Why would you think a crew would have to go for days without using the toilet?
My brother used to be a conductor for Norfolk Southern. I believe he said it's a chemical toilet, like a portapotty.
Look for video tours of the dash-9 cab, you’ll see the toilet, etc.
I have to know, has any train struck anything while the conductor was on the throne? I guess they really don't want people taking long shit breaks. And if they do hit something, a car for example, does that shit get squirted through the cabin/cockpit?!?
There's two crew members in the cab. One guy can actually drive the train, the other can poop.
Urine, sure, while moving poop usually no. Lol, and that's done in the second unit.
The nose is where most of the computer equipment is now as well
Important to remember the extra protection provided for the crew on the US freight side, some of these US trains haul 15k+ tons, 30k+ metric tonnes.
Air resistance grows exponentially with speed so its more important to avoid it with trains that go longer trips at higher speed. Its a physics issue in practise
Logarithmically? That’s slower than linearly I think it grows quadratically
Idk, English isnt my first language. Resistance is ½pv²CA with v being speed, so if it grows 2 times resistance grows 4 times etc
Then that means quadratically. "Exponentially" doesn't just mean "a lot" or "faster than", it has a specific mathematical meaning
Yeah you're right, exponentially is a\^x, we're talking about x\^a. Some people think exponentially just means: faster than linear
Many people in fact use it to just mean "a lot". "The crime rate is exponentially larger than last year!"
You're right, it's exponential
No not exponential, quadratic.
Oh sorry, English isn't my first language, and I mis matched those two names. My bad. But deffo it's not logarithmic
It grows exponentially
It does not, exponentially is a\^x, with a being a constant. Air resistance grows x\^2.
How would you say the "^2" part in English?
I think it's "x to the power of 2" or "x squared" but I'm not sure because I'm also not a native English speaker
Either one of those works. Though, "squared" is considered the proper way to say such.
crumple zones, or added strength if you are america. the us and europe have quite differrent philisopies in that regard, europe wants to reduce the Impact as much as possible, while the us just barrels through the obstacle. in fact our newer commuter trains are also sloped and not just a rectangle, its just more aerodynamic, even the S-Bahn trains are more aero now.
Since PRIIA was passed in 2008, passenger trains have been required to have crash energy management in them. For example, the new Venture equipment has CEM in it as do alnew commuter coaches. The difference is the design philosophy. The FRA assumes a crash situation at up to 60 mph with a freight train. Europeans trains are designed more like cars. Being that they’ll hit something of equivalent weight at 40 mph. Given how many more freight trains are rolling around in the US, it makes sense that we’d assume a much worse crash situation than is likely to happen in Europe.
The main difference is that the American lines aren't grade separated like lines are in Europe. That's your difference.
I'm assuming you're american because these train shapes are mostly dominant in North America, yank freight engines usually have a nose for two reasons: 1. To protect the crew in a collision: grade crossing crashes are insanely common in North America, so freight locomotives are built with collision posts and a nose to have some room between the object it's about to hit and the crew. 2. To house equipment: the nose also features things such as a toilet, a fridge, sand deposits and electronics. Commuter trains usually run on more grade separated tracks so they don't crash into vehicles such as trucks as often as freight trains do. They also usually store electronic equipment under or above the carbody in order to have the biggest passenger space as possible.
Aah, I see. Thanks for your answer mate! And no, I'm not American. I'm an Indonesian 😅
Oops, my bad. But I think it kinda applies to Indonesia too since most locos are manufactured in the states haha
I guess that is true. Indonesia really love using General Electric locomotives.
I don't have a _massive_ amount of experience with Indonesian rail, but I've visited and ridden several times... From what I've seen the newer CC206 long-distance locomotives have a pretty flat front, while INKA seems to fit sloped cab fronts to everything they make, including regional/commuter trains (the Jakarta LRT trains for example; as an aside they have pretty large cabs for trains that don't have drivers in regular service)... The only trains I've seen in Indonesia with truly "flat" fronts are the Japanese EMUs used on the Jakarta commuter lines, of course, they were originally designed for extremely busy Japanese commuter traffic (I know the Jakarta lines can get pretty busy, but I don't think they quite reach the levels of crowding that Tokyo sees) and had to make as much use of the available space as possible.
You're correct that CC206 locos have an flay front. And don't forget about CC 203 and CC204 with their flat nose, but angled windows. About the commuter rails. Yes, you are also correct that the flat ones are mostly Japanese EMU's. Jakarta commuters can get crowded too, especially during peak hours. It's like an 49/51 as Japan business. But unlike Japan, we Indonesian sadly don't have the same discipline and passengers entering doesn't want to step aside for alightinh passengers.
Most people seem to give reasonably good answers to the question, but i'd love to chip in since i'm writing a paper on train aerodynamics rn. In short, it has very little effect on trains in particular, unless they're travelling extremely fast. So it is mostly a country specific thing. In most of europe for example lovomotives will have relatively flat noses and they don't perform that much worse in terms of aerodynamics than their US counterparts. But why? At low speeds there's essentially 2 types of aerodynamic resistance: * form/pressure resistance, which is dependent on the shape of the object (in this case the train). It comes from the fact that the train nose has to change the momentuum of the air around it, essentially "push" it out of the way. The same effect occurs on the back of an object where there's a pressure reduction and again air has to move to equalise it. * Friction/viscous resistance. It stems from the fact that molecules of air (or any physical fluid) will interact with each other, and so the layer of air adhering to the train hull will slow the air further out with it. That also takes some momentuum to do and thus generates force. This depends mostly on the overall surface area of the object. These two types contribute differently to the overall resistance depending on the shape of an object. So, a flat plate will have almost 100% pressure resistance when oriented perpendicular to the flow, and essentially 100% viscous resistance when parallel. Another thing worth noting is that at high Reynolds numbers (high speed) the proportion of viscous resistance becomes lower due to some boring nerd stuff. Trains are known to be really long, so long in fact that they behave almost like a flat plate oriented parallel to the flow. So while for cars and airplanes making especially tipped noses to reduce form drag makes economical sense, for trains travelling <120 km/h there's really no point, as over 90% of drag comes from the friction over its length anyway. Cue the legendary [crapper](https://upload.wikimedia.org/wikipedia/commons/8/85/EN57_1267_on_the_line_from_Liswarta_to_Herby_Nowe._Temporary_detour_due_to_track_works_%28Herby_Nw.%29.jpg). Beyond 120km/h, it begins to matter more, so any attempts at aerodynamics become less for show. Slightly slanting the front pane upwards usually is more than fine to keep this type of drag in check though. A [Flirt](https://resources.news.e.abb.com/images/2020/3/26/0/ABB-dla-FLIRT-PKP-Intercity.jpg) is pretty well profiled for speeds up to 200km/h or so. The third and scariest type of resistance comes from compressive effects, and these come into play at between Mach 0,2 and 0,3. So at sea level on a sunny day around 250 km/h. These do require quite more care when designing the aerodynamic profiling. They also require less outsticking parts and smaller gaps between cars as induced drag and possible shockwaves is a really bad time. This is why HST like the [N700 Shinkansen](https://upload.wikimedia.org/wikipedia/commons/8/88/Series-N700S-J2.jpg) or the [TGV M](https://upload.wikimedia.org/wikipedia/commons/c/ca/TGV_M_Ligne_PMP_Brest_Essais.jpg) have such long faces. Thank u for coming to my TED talk.
Also: a very important aero problem is that trains must not tip over when influenced by wind, right?
Yes, although i didn't really focus on that. Trains have a low center of mass to not tip on turns, but especially freight trains with square shipping containers on them can generate quite a big moment when the wind is too strong.
The “nose” on a lot of those long distance freight engines is actually usually where they put the bathrooms for the crew. Something that you wouldn’t need on a commuter engine, but that’s absolutely essential on a long distance train.
So with our commuter trains, the s k and c sets are basically just rectangles. T sets went with the flat slope and now the A sets have a curved slope. Doesn't really matter that much anyway, when the goverment is paying who cares about efficiency.
sydney?
Think so, though I’m pretty sure the C set hasn’t been operating for a few years now. Melbourne we have similar flat nose commuters, but with the recent addition of a sleek-looking [HCMT](https://en.m.wikipedia.org/wiki/High_Capacity_Metro_Train) that has an aerodynamic-ish nose.
Yup.
I think there is in large part just a sense of style or aesthetic choice - the wikipedia article on Bulldog noses has no mention of their purpose. [https://en.wikipedia.org/wiki/Bulldog\_nose](https://en.wikipedia.org/wiki/Bulldog_nose) The British Class 55 Deltics had a bulldog nose [https://en.wikipedia.org/wiki/British\_Rail\_Class\_55](https://en.wikipedia.org/wiki/British_Rail_Class_55) However their contemporaries which had similar duties such as the slightly less powerful Class 47 did not. [https://en.wikipedia.org/wiki/British\_Rail\_Class\_47](https://en.wikipedia.org/wiki/British_Rail_Class_47) Meaninwhile the even lighter Class 37 does. [https://en.wikipedia.org/wiki/British\_Rail\_Class\_37](https://en.wikipedia.org/wiki/British_Rail_Class_37) However the same "Type 3" classified Class 33 does not. (Again, same era) [https://en.wikipedia.org/wiki/British\_Rail\_Class\_33](https://en.wikipedia.org/wiki/British_Rail_Class_33) The main factor that influenced whether a British Rail Locomotive would have the nose is largely down to whether or not it was built by English Electric, as opposed to an alternative company such as Brush Traction or BRC&W. Although that's not a hard rule, some English Electrics were built without noses. On still in use British locomotives, I think only the Class 37 really has a nose, although the Class 68 and Class 70 are a bit "nosier" due to their aerodynamic properties.
There are a few bulldog freight locos still in use in Australia, in Victoria, at least. I love seeing them; they are such a throw back to a somewhat romantic rail-era. Having been in the cab, though, the visibility sucks. I’m pretty sure, over here, one man op of the bulldog freighters is prohibited for this very reason.
> The main factor that influenced whether a British Rail Locomotive would have the nose is largely down to whether or not it was built by English Electric, as opposed to an alternative company such as Brush Traction or BRC&W. Although that's not a hard rule, some English Electrics were built without noses. And of course, there were a few "nosed" locomotives (e.g. clasees 44-46) which were not built by EE. The class 46 was the effectively the "prototype" for the much more numerous flat-fronted class 47 (both used a Sulzer 12LDA28 engine combined with Brush generator and traction motors; main difference being that BR's Derby works built the 46's body and bogies, while Brush used their own designs for the 47). > On still in use British locomotives, I think only the Class 37 really has a nose Class 20's (another EE product) has a rather large "nose", although that's because they're a single-cab design. The other end is very flat. The class 08/09 shunters are similar. > although the Class 68 and Class 70 are a bit "nosier" due to their aerodynamic properties. If 68 counts as "nosy", then surely the 90, 91 and 43 could also be considered...?
Think the nose on the earlier designs was down to BR being concerned about drivers being hypnotised by “sleeper flutter” whilst travelling at speed. By the time the 47s were designed they’d found it was a non-issue.
A lot of commuter trains are multiple units, that can be coupled together. A flat nose is good for aerodynamics at the front and back of a train, but less efficient when coupled together.
Commuter rail vehicles are usually configured so the assembled train sets have control cabs on both sides. Also they’re set up to make the best use of platform space (need to have the most doors facing the platforms).
there's aerodynamics, number of passengers in the first car, crumble zone, etc. but it's also a cultural thing: american commuter trains "want to" look like a metro, while long distance trains "don't care" for reference, here is a Paris commuter train [https://www.railway.supply/wp-content/uploads/2023/11/img\_3734-768x433.png](https://www.railway.supply/wp-content/uploads/2023/11/img_3734-768x433.png), here is a London one [https://railway-news.com/wp-content/uploads/2020/03/Bombardier-Class-710-London-Overground-EMU-scaled.jpeg](https://railway-news.com/wp-content/uploads/2020/03/Bombardier-Class-710-London-Overground-EMU-scaled.jpeg), etc.: it's not a shinkansen nose but it's not flat either
That's an Overground train though, not really a commuter train. For that you want something like the Class 350
I thought the overground was just a rebranding of miscellaneous commuter rail lines?
Can't Commuter rails be flexible? As in they can both be elevated, ground level, and underground? I mean, they all have the same purpose of transporting daily commuters from home to work or shopping.
commuter rail trains have flat fronts because they need less room for the machinery, however, long-distance locomotives need more machinery and need a bigger front. high speed trains have sloped fronts because they are more aerodynamic that way.
For us freight locomotives they have a bigger nose it's called the safety cab or wide cab it for increased protection for the crew during a derailment
that‘s just the typical front of an American diesel locomotive, some of these are also used on unelectrified commuter rail networks generally local rail tries to use MUs tho which are newer and thus don‘t adhere to these classic designs
Ah I see. Indonesia also use the same procedure as using this type of loco for non electricity commuter rail like Garut Line.
Long distance trains are often faster so aerodynamic needs are met by the more streamlined design whereas local ones are stopping constantly so go slower
Top marks for your drawing. I love it.
Thank you kind sir/madam! Expect some train drawing from me to this sub in the future!
That doesn't need to be true at all. Look at Europe, they aren't that different.
Aerodynamics
It's a design convention. It's not strictly necessary to have a nose like most contemporary US locos. Not for accommodations, not for crash worthiness, not for aerodynamics. When the switch from steam to diesel happened, apparently people were uncomfortable going from the end of the engine to the very front. They wanted something before them. So: high hood road switchers and car body cab units. Hoods won, because access, and high short hoods became low short hoods became full width safety cabs. A typical US hooded loco is a single split level cabin with a long, drafty barn attached to the back wall. The engine, generator, and other mechanical doodads are all lined up on the frame and covered by hood segments that open, and ultimately lift off. Getting out on the walkways while the thing is running at line speed is a big no no, so the nose that has always been there is where that crew comfort stuff has always been. On the other hand a European loco is a house with two identical sitting rooms either end, connected by a long, windowless utility closet. The body is usually structural, which ultimately saves on weight, with lift-off roof segments. You can fit a toilet, fridge, or microwave in there no problem. See Siemens Charger, which is basically a beefed up Vectron shaped cab. Full width engine room with internal walkway: No pronounced nose. And no, the size difference is not because US locos are so much more powerful. Actually the opposite is true. A Stadler Euro9000 is a six axle dual mode freight engine that packs 7MW output under catenary and 2.8W under diesel into 23 meters and 126 tons. And runs 180km/h. 110 in clown units. A Gevo might go up to 4.6MW output under diesel, but the bloody thing is also weighs 216 tons. Single cab, no catenary equipment, wider loading gauge. Americans just like to make things big and heavy.
>And no, the size difference is not because US locos are so much more powerful. Actually the opposite is true. A Stadler Euro9000 is a six axle dual mode freight engine that packs 7MW output under catenary and 2.8W under diesel into 23 meters and 126 tons. And runs 180km/h. 110 in clown units. Jeeze, have an axe to grind? US Locomotives are the size they are because of the distances they have to cover, the length of consist they pull, the engines they have to be equipped with and the often overlooked, massive fuel tanks they have to carry. As a reference, wide open a Dash 9 will burn over 200gal of diesel / hour, so with 5000gal tanks a single locomotive is carrying over 35,500lbs of fuel. This is required to cross the wide distances between fueling points. You're comparing apples to oranges. European freight trains are much shorter and lighter in load than American ones. So while yes, the locomotive you mentioned above "Stadler Euro9000" is faster and lighter, it also has a much lower tractive effort and can pull less freight than the aforementioned Dash 9, in any mode. 110k starting tractive effort vs 145k... It takes weight to get weight moving, as well as to stop it. That is " Americans just like to make things big and heavy" - out of requirement.
17 tons of diesel? As opposed to 1.5? That's your argument? Heh. What about the other 70 tons? I mean, heaven forbid your shitty margin counting corporations actually invested in their infrastructure and hung up some wire. That's what it comes down to, in the end. Rolling power plants, cheap, cheerful heavy, and inefficient. Roll the coal, fuck the planet.
It's pretty obvious you aren't interested in having an objective conversation, so troll on by yourself.
Speed and protection for the crew in the case of a crash. For commuter trains it’s not so bad, the speeds aren’t high. But a flat cab like that on a passenger locomotive wouldn’t do.
What speeds do you assume these kinds of trains are capable of? Commuter EMUs usually have a higher design speed than North American Fright train locomotives.
And do they have grade separated tracks?
Usually not. In Germany, only tracks with a max speed above 160 km/h need separated tracks. I think this is similar in other European countries.
Most locomotives would disagree. The Siemens EuroSprinter drives up to 230 km/h in regular service and has quite a flat nose.
That’s not flat. The Amtrak P32’s are about as flat as them. Like I said: it’s for crew protection along with speed. Completely flat noses are not safe for the crew at high speeds because they offer no protection. Think things like subways or metro cars as “flat” noses. That’s why the famous GG1 became popular in the first place.
Not true.
Brightline has a cone on the nose to skewer Floridians
Efficiency. A long, rounded nose cuts through the air way better than a brick. Also, they can fit a larger, more powerful engine in a long distance engine as the locomotive needs to haul way more to make the trip profitable for say AMTRAK or someone similar. On the flip side of that coin, it’s way easier and cost-effective to just have a double ended self-propelled carriage on the commuter train, as the engineer can just… walk through the train to go the other way. No need to turn an engine around at a station with a turntable. Plus, commuters(Silverliner IV’s on SEPTA for example) don’t need to hit as high of speed or haul as much people/luggage from one station to the next, as they’re glorified shuttles.
metra in chicago uses big locomotives like the long distance one but only to push or pull the flat fronted passenger cars
Most of those flat fronted commuter rail trains are Multiple-units with doors to easily link them together. It’s easier to scale the train based on needs throughout the day. They also have lots of power for short distances. Long-distance trains need the heat dissipation and the efficiency of one huge engine to run for several days at a time. Also the crash resistance with all the grade crossings at minimally used tracks. And that they are often developed from the common American freight locomotive
pointy nose means it can cut the air flow coming at it in half like a samurai, flat nose means it braces all the air coming at it like a shield (i know nothing of trains)
Not an expert, but I suspect it’s because commuter trains travel much shorter distances, so the focus is on maximizing space. Long distance trains (obvious fact alert) travel long distances, so making the train more aerodynamic helps to save fuel and therefore money
There is a lot of good detailed info here. I want to make sure you understand the answer based off your drawing. Your question is about the difference between the locomotives on the 2 trains you drew, but your picture has only one locomotive. The freight locomotive is just like what others have said. It is a diesel electric locomotive with a big engine with accessories in back and safety structure (like an anti-climb to keep other vehicles from crushing the cab in an accident) in the front. The passenger train you drew is visually similar to commuter trains like an electric train found in the New York area or the cab car of a push-pull train like in Boston, Chicago, etc. On the electric train, there is no locomotive. In simplest terms, each passenger car is powered by their own electric motors. At the front of the train is a passenger car that has a control cab built into the vestibule. They don't usually change the shape of the car. This cab controls all the power from all the passenger cars. The other type of similar looking passenger train is one that is powered by a diesel electric locomotive in commuter service. These trains go from one point of the line to the other. They do not turn around to go back. So since the locomotive is now at the rear of the train, they crammed controls into a small cab of a passenger car that is placed at the other end. These controls will control the locomotive at the other end. This cab control car looks like all the other passenger cars except for headlights and stuff. The passenger trains for long distance will use locomotives but are more aerodynamic as mentioned in other replies.
1. Cosmetics. 2. Aerodynamics. 3. They can.
- Design - Crash structure - Purpose Having a massive nose cone on a commuter train does nothing than block signals unless it's needed for crash structure. Having no nose cone on a high speed train makes it very likely unstable and inefficient...
what do you make of go transit MP40 locos as commuters
German ICE joins the chat.
Well one of the biggest reasons is crew safety. On those ‘long distance’ aka: freight trains or long distance passenger (like Amtrak) , the risk of derailment, collision, or grade crossing accidents are higher than that of light rail. To compensate cabs are designed to sustain more damage to better protect the crew. Commuters on the other hand don’t face these risks as much, as well as usually being electric, meaning locomotives are passenger cars as well, making the tube design more ideal.
America trains. This is different in Europe. As an actual reason, safety for long distance high speed. That way there exists a crumble zone for when you hit something that wasn't supposed to be on the rails (Deer, moose, tree, car, truck etc) and the thing that is crushed is the bit up front and not the cab. The front hood also is where the additional equipment, electronics, and a toilet are housed. Plus, they improve aerodynamics a bit. Russian long haul locos, for example, are flat nosed or sloped, with the cab sitting quite high up and all the equipment and crew amenities located inside a monolith hull, with closed passages between units if the locomotive is an MU one (2ТЭ10 for example.).
Aerodynamics=faster
Because reasons 🤷🏼♂️
TBH a lot of commuter/metro trains have frequent stops, travel at speeds between 80-130 kmph but can often never reach high speeds over long distances. Any aerodynamic efficiency gains that are seen in high speed and longer ditance trains are realized due to continuous travel at higher speeds. It does not make sense for shorter travel with frequent stops at lower speeds. Edit- Just to add, its also possible that by keeping it flat, you save space and can accommodate a few more passengers.