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Why were unit fronts designed this way?

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bramling

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Does it in practice, though? When driving a car you need all round vision, including sideways and behind you. When driving a train you need to be able to see the signals, which are positioned in front of you.

Yes and no. If everything is well positioned then what you say is quite right. The difficulty is that this isn’t always the case, especially when one considers issues like platforms where the cab may stop close to a signal, or things like ground shunting signals. Here you then end up with a situation where signals aren’t in front of the driver like you say, but off to one side or low down. Repositioning of signals is costly and not always easy to achieve, so one can end up with issues.

Another issue is things like depot working, when the driver will be looking for hazards like staff on walkways. Here the driver may well need visibility to the extreme right and low down, for example. More of a problem if the driver is sitting further back from the window, which tends to be the case in newer gangway stock.

Cars aren’t much different. I have a 2000 BMW 5-Series and an equivalent 2016 model. The visibility on the latter is considerably worse for various reasons.
 
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hexagon789

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The 109mph record was achieved during a test run with a streamlined front end fitted.
I'd forgotten that and presumably they went with a set on new wheels as well to maximise the speed potential.


Most of my experience of them was between 1970 and 1975. 100mph was regularly indicated on Saturdays on down trains between Chelmsford and Colchester, and occasionally even on the run down through Ingatestone, (which was necessary to make their 8 1/4 minute start to stop timing between Shenfield and Chelmsford possible).
I suppose it depends on a number of factors, but I know that a 10-car set in original formation was supposed to be able to make 100 (presumably the increased power-to-weight from the added two-car set), but a four-car alone was supposed to top out in the nineties most of the time as the wheels wore down. On minimum diameter balancing speed was about 90mph.

Admittedly I read this some years ago so I may be slightly out on some of the details but I distinctly recall noting that they apparently couldn't always quite make 100 ordinarily despite that being their design speed.

Definitely better performance than SR EMUs though, no doubt of that particularly at higher speeds
 

Darandio

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Didn't it have the prototype HST cab strapped to the front of it?

It's got similarities but it isn't the cab from that.


E3173%20with%20nosecone%20A%20Betts.JPG
 

edwin_m

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If, as seems likely, this "nosecone" was fitted around an unmodified cab front, then the driver's view must have been atrocious. From their left hand seat they would only have had that small window somewhere beyond the existing cab front and off to the right, making sighting of left-hand signals impossible. Did they have a "spotter" standing behind them in centre of the cab?
 

AM9

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Yep:

...has a selection of photos.
Actually, I think that this picture was from the earlier tests and the same streamlining was used later on early HST trials. I've found a link to an article about the tests here: http://www.traintesting.com/high_speed_testing.htm The tests were more about running trains faster than 100mph which was the limit on the national network at that time. The AM9 as it was known at the time was fitted with Commonwealth bogies (including the motored ones) that were known to be suitable for high speed running, but there were also trials of the DOC2/BT5 bogies (the precursor of the MKIII standard BT10 design) which was better suited to higher speeds than the BR1 and even the B4 type that was fitted to the MKII coaches.
The class 86 fleet at the time had axle hung motors which with the resulting high unsprung weight was known to increase track wear and even damage, so the test locomotive was fitted with flexicoil augmentation to reduce the impact on the track. These were later fitted to the whole class 86 fleet. There was also monitoring of the then standard Stone-Faiveley pantograph at speed. The results of that probably led to the 'scissors' type that was introduced later in the '70s to the locos and eventually the introduction of the Brecknell-Willis type which is the current standard. As far as the AM9 results, it was found that their maximum speed wasn't reliable enough to operate services that were times for speeds in excess of 100mph, although had weak-field modifications (similar to that applied later to the 4-CIG 'Greyhounds) been considered for them, the intermediate services on the WCML may well have been provided by a derivative of the AM9s.
 

rebmcr

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If, as seems likely, this "nosecone" was fitted around an unmodified cab front, then the driver's view must have been atrocious. From their left hand seat they would only have had that small window somewhere beyond the existing cab front and off to the right, making sighting of left-hand signals impossible. Did they have a "spotter" standing behind them in centre of the cab?
During that era, locomotives had two drivers as a matter of routine — a staffing holdover from the driver + stoker present on steam footplates.
 

edwin_m

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During that era, locomotives had two drivers as a matter of routine — a staffing holdover from the driver + stoker present on steam footplates.
They actually had a driver and "secondman", formerly the "fireman" and not necessarily themselves qualified as a driver. I don't think "stoker" has ever been official terminology on railways - more a nautical term. But I'm surprised even in the 70s that a driver was allowed to drive essentially blind with someone else spotting the signals, at speeds considerably above normal. Perhaps it was only run under possession so the signals didn't matter?
 

AM9

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They actually had a driver and "secondman", formerly the "fireman" and not necessarily themselves qualified as a driver. I don't think "stoker" has ever been official terminology on railways - more a nautical term. But I'm surprised even in the 70s that a driver was allowed to drive essentially blind with someone else spotting the signals, at speeds considerably above normal. Perhaps it was only run under possession so the signals didn't matter?
If you read the article that I posted a link to in post #102, you can see that the tests were conducted under full possession of both up and down fasts early on three consecutive mornings. Thus there was relatively little chance of a random event requiring the level of driver view normally available. Given that there were probably a second person present (maybe more if measurements were being taken), I think that the risks were acceptable.
 

py_megapixel

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With regards to the Desiro fronts -

It will be interesting to see if EMR end up with the 185s - which seems likely - how similar the fronts look to the 360s in the same livery
 

oliverpckehoe

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With regards to the Desiro fronts -

It will be interesting to see if EMR end up with the 185s - which seems likely - how similar the fronts look to the 360s in the same livery

A 185 and a 360 are almost identical except for the light clusters, so imagine the difference between an early 377/1 (or /3) and the newer 377s.
 

O L Leigh

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379s are good example of a gangwayed unit that was required to be for the refreshment trolley to traverse the length of a train, but with the trolley service axed and the the trains on outer suburban duties they invariably remain locked, and most wouldnt be bothered.

There is another rather more pressing reason why they’re not currently making-up the gangway connection between these units that has nothing to do with the trolley. They seem to have developed a rather nasty habit of coming apart, so the gangways are kept closed for safety reasons.

The gangwayed CAF units look like they should have a good view with a reasonably large flat window

I have to take issue with this. I spent a decent amount of my afternoon down at Tyseley and took the opportunity to make a first-hand side-by-side comparison between the Cl196 and the existing Electostar-style Cl172; at least from ballast level.

Of the two, it is the Cl196 that has the smaller windscreen. They may look big, but that’s a bit of a trick because they are angled back towards the edges. From head-on they are noticeably smaller than those on the Cl172. The gangway on the Cl196 also seem a little wider and definitely protrude further forward. Depot staff were also not terribly impressed because they say there are screens intruding on either side inside the cab.

I think that, like other recent gangwayed classes, the view straight ahead will be OK but the peripheral vision will be extremely restricted. I imagine that it will be no better than from the seat of a Cl172 and possibly even a bit worse.
 

Goldfish62

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The front cover photo of the latest Modern Railways is of the front of a WMT Class 730. The offside screen looks to be more vertical and inset than the nearside screen. I'm wondering why this is, unless it's just an optical illusion.
 

hexagon789

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The front cover photo of the latest Modern Railways is of the front of a WMT Class 730. The offside screen looks to be more vertical and inset than the nearside screen. I'm wondering why this is, unless it's just an optical illusion.
I only see one screen - in the Secondman's-side window?
 

swt_passenger

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I only see one screen - in the Secondman's-side window?
Are you possibly using “screen” as in information display? Because they could also be “screens” as in windscreens in both sides.

But looking at the magazine, there does seem a difference in how they look.
 

hexagon789

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Are you possibly using “screen” as in information display? Because they could also be “screens” as in windscreens in both sides.

But looking at the magazine, there does seem a difference in how they look.
Yes, because that's what I think of when the word "screen" is used. I would use the full "windscreen" to describe such exactly for the reason that it's unambiguous.

(To be honest I've never used or indeed seen screen for windscreen always the modern sense of the word for an electronic display.)

Now that I understand we are talking about windscreens - to me the 2nd-man's side looks flat, the driver's side looks slanted. Not sure if that's the camera angle or if that's actually the case though, but they certainly appear different
 

Energy

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Yes, because that's what I think of when the word "screen" is used. I would use the full "windscreen" to describe such exactly for the reason that it's unambiguous.

(To be honest I've never used or indeed seen screen for windscreen always the modern sense of the word for an electronic display.)

Now that I understand we are talking about windscreens - to me the 2nd-man's side looks flat, the driver's side looks slanted. Not sure if that's the camera angle or if that's actually the case though, but they certainly appear different
1612615557824.png
Definitely, the left side has a gap while the right doesn't
 

Domh245

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I think it's just a trick of the light - the black front hides the shape quite well!

This picture is from the offside and quite clearly shows the same sort of recess around the window as can be seen on the offside window in the picture in post#115 (the windscreens aren't fitted but you can quite clearly see the apertures, although this picture also shows the same view, just less clearly)
 

hexagon789

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View attachment 90085
Definitely, the left side has a gap while the right doesn't
It certainly has the same appearance of the MR front cover shot, but I'm still not sure whether it's just an optical illusion

I think it's just a trick of the light - the black front hides the shape quite well!

This picture is from the offside and quite clearly shows the same sort of recess around the window as can be seen on the offside window in the picture in post#115 (the windscreens aren't fitted but you can quite clearly see the apertures, although this picture also shows the same view, just less clearly)
I'm still unsure either way, I think a dead head-on shot is needed.
 

Goldfish62

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Yes, because that's what I think of when the word "screen" is used. I would use the full "windscreen" to describe such exactly for the reason that it's unambiguous.

(To be honest I've never used or indeed seen screen for windscreen always the modern sense of the word for an electronic display.)

Now that I understand we are talking about windscreens - to me the 2nd-man's side looks flat, the driver's side looks slanted. Not sure if that's the camera angle or if that's actually the case though, but they certainly appear different
Sorry, I was using everyday bus terminology (in my area anyway) - obviously different from the railways!
 

Fincra5

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Class 377. Rather ugly front in my opinion but also offering only a very limited view to the right for the driver whereas other types of DMU/EMU offer a full field of vision from the front window. Surely the cab width, less than half the width of the train is rather claustrophobic.
As someone who actually drives them, the view isn’t that bad! Probably one of, if not, the best FoVs for a gangway unit. As others have pointed out, the gangway allows passengers and staff to walk through the train. Much as you could on the old Slamdoor trains they replaced...

This is not only useful for security and revenue duties but key for short platforms, where you have a 12 car train but only 4 coaches will fit!
 

Recessio

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I actually think the 377s are pretty good looking for a gangwayed unit. In my mind, if privatisation hadn't happened and BR had continued to develop sprinters, I think the 377 is probably the closest (in terms of looks) to what they'd have developed for a 3rd Gen DMU.
Isn't the Electrostar/Turbostar design pretty heavily inspired by the BR Networkers? I figure it would be pretty much exactly what they would have looked liked - of course if privatisation hadn't disrupted the market, they may have just used Networkers to replace all the slamdoors rather than Electrostars 5/10 years later.

Would be interesting to see a mockup of a gangway Networker...
 

Goldfish62

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Isn't the Electrostar/Turbostar design pretty heavily inspired by the BR Networkers? I figure it would be pretty much exactly what they would have looked liked - of course if privatisation hadn't disrupted the market, they may have just used Networkers to replace all the slamdoors rather than Electrostars 5/10 years later.

Would be interesting to see a mockup of a gangway Networker...
The mockup of the mainline Networker, which was cancelled before ordering, did indeed look very much like the gangwayed Electrostar.
 
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