Imaginary Locomotives

[scots region]

On the other hand, a flat sided locomotive is surely easier to clean even by conventional methods. Though I have read one account that the paint on Channel Packet was so rough that it shredded the cleaners rags. 

[Justang]

On 25/10/2020 at 21:03, MikeOxon said:

Only because Dean's 4-6-0 was popularly known as the 'crocodile' and wasdesigned for the same job as my version.

I had a go back in 2014 on Page 14 of this thread:

 

 

 

 

That looks really nice. I quite like the angular, yet streamlined, shape of its features. The image might seem steampunk, but wasn't that a feature of Great Western engines since broad gauge days? Their management seemed quite keen on keeping to tradition, whilst wanting their railway to seem modern. The logo on the smokebox door seems to fit with this modern image, whilst being traditional in what it represents. I don't see why that streamlined concept would seem ridiculous. I like it.

[rodent279]

1 hour ago, Gibbo675 said:

Hi Mark,

 

Going fast is not the problem it is the propagation rate of the vacuum brake that is the problem with signalling block lengths as they were to be able to bring trains to a stand without re-signalling the entire railway or leaving larger gaps between trains within the timetable. This was the very reason for the fitting of air brakes to diesels, although strangely not the AC electrics from new, and the conversion of almost all of the passenger and goods stock to enable higher speeds to be attained.

 

The design brief of both the HST and APT were to be able to use the existing signalling and line capacity at the higher speeds. This was achieved through the application of new braking technologies.

 

Gibbo.

I thought the AC electrics, like diesels, had straight air loco brakes, and vacuum train brakes?

[Gibbo675]

38 minutes ago, rodent279 said:

I thought the AC electrics, like diesels, had straight air loco brakes, and vacuum train brakes?

Hi Rodent,

 

The early series AC electrics didn't receive duel train brake capacity until they were refurbished, unlike various diesels such as, 33's, 37's and 47's that received dual train brakes from new. There are probably other classes of diesel but that requires getting a book off the shelf !

 

Gibbo.

[melmerby]

2 hours ago, Gibbo675 said:

Hi Kieth,

 

Surely saving labour on the cleaning of locomotives meant that the War Ministry had more men to put through the meat grinder, that would no doubt please them immensely whatever the locomotives were called.

 

Gibbo.

There was a shortage of locomotives, so anything that theoretically could pull a train full of military goods etc. was also welcome.

[The Johnster]

The frontal styling of the A4, Mikados, and hush hush, as well as Bulleid’s ‘air smoothed locos (he’d been involved with the LNER designs) were also intended to improve smoke lifting, with some success.  Smoke and steam from small chimneys on locos with big boilers, and those with streamlined casings, had been a problem since the early part of the century, when heavier trains coupled with the requirement for higher speeds meant that locos needed bigger boilers to feed the bigger cylinders. 

 

[rockershovel]

4 hours ago, Northmoor said:

Since air resistance rises in proportion to the cube of the speed, every extra MPH means big increases in power required.  More power is going to mean more or bigger cylinders (within the limits of the loading gauge) and this is going to mean progressively bigger rods, which means bigger reciprocating forces (which also rise with the square of the speed, even at constant mass).  What this all means is that vibration is going to damage the track before steam locomotives go much faster, unless you start using a lot of cylinders with geared drive or better still, steam turbine/geared drive. 

 

While the railways realised the futility of chasing speed headlines after WW2, what they were far too slow to realise was the need to improve productivity, especially with freight.  The fact that by the end of steam, huge quantities of coal were still being shifted in unfitted, 16t 4-wheel wagons (look at what the Americans or Germans were using by then), says a lot about the inertia in the industry and many of their (nationalised) customers.

 

Germany had the great advantage, as it would prove, of its hereditary aristocracy and attendant banking sector and

their constant demands for profits being swept away by the aftermath of WW1 and a new meritocracy of industrialists replacing them. They, in turn, had the ear (and pockets) of the populist, totalitarian regime which replaced the old political class. Then they went through it all AGAIN after 1945, when failure simply wasn’t an option. 

 

Imagine where OUR coal industry could have been, or our rail sector, backed by a government who demanded modernity and productivity, and ruthlessly protected the home market and home industry,  from 1920 onwards...

 

[rodent279]

On 25/10/2020 at 21:16, JimC said:

The pairs of railcars sometimes ran with an unpowered coach in between, so a mix of powered and unpowered cars is a very obvious extension.

Going back to the stretched GWR railcar idea, the twin car units each had 2 105hp engines in. Assuming 2 engines in each car, that gives 1680hp for an 8 car rake, with an all up weight, assuming 36 tons per car, of 288 tons. Sounds like a recipe for adequate performance, but probably not enough installed power to better King or Castle timings on the same load. However, higher availability and shorter turnround times might have been an attraction for an intensive London-Bristol service, if the demand was there in those days.

Edited October 27, 2020 by rodent279

[rockershovel]

Speaking from experience of commuting longer distances, 70 plus miles daily and 150 plus miles weekly or alternate weekends, I don’t believe that commuters are greatly interested in relatively small increments of time or speed. 

 

The fastest possible journey time, Peterborough to London was 44 minutes, but the chances of getting a train which did that were small, because they just weren’t scheduled sufficiently often. Most commuters, most of the time reckoned to take 50-60 minutes depending on exactly which train you caught, and provided that was achieved consistently (with delays at Peterborough Town Bridge being hugely unpopular, although the real effect on scheduling was minimal) no one really cared greatly; the main focus of discontent, being the overcrowding, always present and at times, severe to the point of being downright dangerous. 

 

The electric services were immensely unpopular, being uncomfortable, slow (typically 70-95 minutes) and at times grossly overcrowded - all for no saving in fares. 

 

These days (in the sense of “until the onset of the present lunatic situation”), I don’t use the HST at all if I go to Town. It’s three times the cost of the electric, for a typical saving of 15 mins or so, which I don’t regard as worthwhile - and commuters can now by cheaper seasons for the journey, offering an identifiable balance between cost and time. 

 

Hence my scepticism (to the point of disbelief) over HS2. 

 

[Compound2632]

14 hours ago, Northmoor said:

While the railways realised the futility of chasing speed headlines after WW2, what they were far too slow to realise was the need to improve productivity, especially with freight.  The fact that by the end of steam, huge quantities of coal were still being shifted in unfitted, 16t 4-wheel wagons (look at what the Americans or Germans were using by then), says a lot about the inertia in the industry and many of their (nationalised) customers.

 

This has been discussed numerous times. The railway companies had been experimenting with higher-capacity wagons since the turn of the century. The resistance came from the coal owners (before nationalisation) as they were unwilling to invest in the rebuilding of colliery facilities to handle larger wagons and also from the smaller merchants who didn't want the overheads associated with handling more than 8 or 10 tons at a time of any particular type of coal. In the early days of nationalisation, there still wasn't the money to improve pithead infrastructure - or at least it wasn't the priority for investment; miners' working conditions and amenities came first. The problem was finally addressed by the nationalised industries with the move to MCR operation.

[The Johnster]

The advantage to passengers from timetable reductions is marginal, and reliability of arrival times is far more important to them (particularly commuters who have to get to work on time).  There is a clear advantage to the operating railway’s efficient usage of capacity, though; faster, heavier, trains can move more traffic through a section of railway over a given period of time (especially if they all run to the same timings as headways can be reduced; service frequency is improved).  The increased profitability that results is worth the cost of the bigger, faster locos and the increased track maintenance. 

[Northmoor]

42 minutes ago, The Johnster said:

The advantage to passengers from timetable reductions is marginal, and reliability of arrival times is far more important to them (particularly commuters who have to get to work on time).  There is a clear advantage to the operating railway’s efficient usage of capacity, though; faster, heavier, trains can move more traffic through a section of railway over a given period of time (especially if they all run to the same timings as headways can be reduced; service frequency is improved).  The increased profitability that results is worth the cost of the bigger, faster locos and the increased track maintenance. 

I understand that is much of the justification of the proposed line speed on HS2.  Running at near 200mph requires a significantly smaller train fleet than running at 125-150mph, so you trade off the increased power consumption of the fewer, faster trains against more trains operating at lower speed.

[tomparryharry]

It is true that Gresley  was convinced that an A4 pacific was 'good'  for 130mph.  Sad to say, the appointed test day ended in sadness as the Western 28xx booked for the high-speed run, was double booked for a boiler washout at Banbury shed.

[The Johnster]

7 hours ago, Northmoor said:

I understand that is much of the justification of the proposed line speed on HS2.  Running at near 200mph requires a significantly smaller train fleet than running at 125-150mph, so you trade off the increased power consumption of the fewer, faster trains against more trains operating at lower speed.

Think of it as a pipeline, with the speed of the water running through it enabling more water to be carried between two points in a set time.  But it all falls apart if any trains are significantly slower or faster than the norm, because the faster trains will encounter adverse signals as they bunch up behind the slower ones; your pipeline is partially blocked and the flow is slowed.  It also means that all trains must call at all the stops, which must be evenly spaced

.  The faster you go the more passengers you can carry and the less trains and track you need.  
 

This brings us to perhaps the most significant argument for HS2, and the one least mentioned in the media, which concentrates on London-Manchester in 90 minutes or whatever it is.  The traffic that is taken from the existing network by HS2 will be the current 125/140mph stuff.  It’s removal from the existing network will mean that the speed range of trains using it can be narrowed from the current 60mph-140mph range, further increasing the number of new paths available on routes currently at capacity while passenger numbers are rising and freight is increasing as well.  
 

The motorway network is clearly over capacity and unfit for purpose.  HS2 will improve the situation here as well, as high speed trains will reduce car use, as will the increased commuter capacity on the ‘normal’ tail network, which well also be able to relieve some of the commercial motorway traffic.  
 

Whether these undeniable improvements are worth the immense cost is not for me to say; I don’t know enough about it!  I know the current situation is going to get worse, though. 

[RLBH]

1 hour ago, The Johnster said:

Whether these undeniable improvements are worth the immense cost is not for me to say; I don’t know enough about it!  I know the current situation is going to get worse, though. 

It's one of those situations where, if you think the solutions are expensive, just wait until you see the cost of not solving the problems!

[Gibbo675]

3 minutes ago, RLBH said:

It's one of those situations where, if you think the solutions are expensive, just wait until you see the cost of not solving the problems!

Attempting to solve a debt problem with a currency created from debt is far too much like drinking more alcohol in an attempt to become sober.

[DCB]

1 hour ago, The Johnster said:

Think of it as a pipeline, with the speed of the water running through it enabling more water to be carried between two points in a set time.  But it all falls apart if any trains are significantly slower or faster than the norm, because the faster trains will encounter adverse signals as they bunch up behind the slower ones; your pipeline is partially blocked and the flow is slowed.  It also means that all trains must call at all the stops, which must be evenly spaced

.  The faster you go the more passengers you can carry and the less trains and track you need.  
 

This brings us to perhaps the most significant argument for HS2, and the one least mentioned in the media, which concentrates on London-Manchester in 90 minutes or whatever it is.  The traffic that is taken from the existing network by HS2 will be the current 125/140mph stuff.  It’s removal from the existing network will mean that the speed range of trains using it can be narrowed from the current 60mph-140mph range, further increasing the number of new paths available on routes currently at capacity while passenger numbers are rising and freight is increasing as well.  
 

The motorway network is clearly over capacity and unfit for purpose.  HS2 will improve the situation here as well, as high speed trains will reduce car use, as will the increased commuter capacity on the ‘normal’ tail network, which well also be able to relieve some of the commercial motorway traffic.  
 

Whether these undeniable improvements are worth the immense cost is not for me to say; I don’t know enough about it!  I know the current situation is going to get worse, though. 

Or maybe think of it like building a new high speed cross channel Ferry for Dover - Calais in 1941.   

[The Johnster]

Eh?  Don’t follow, but it’s nearly my bedtime and I’m not at peak efficiency, not that peak efficiency is much to erite home about in my case...

Edited October 27, 2020 by The Johnster

[The Johnster]

Mind you, a high speed cross channel ferry would have been very useful in 1944!

[PenrithBeacon]

6 hours ago, The Johnster said:

Mind you, a high speed cross channel ferry would have been very useful in 1944!

Not so much in 1940

[62613]

7 hours ago, PenrithBeacon said:

Not so much in 1940

I don't know; the high-speed cross-channel ferries in 1940 were 'V' and 'W' class destroyers, among others!

 

[PhilJ W]

Just to think if the Hovercraft had been invented twenty years earlier (late 30's) it could have made a great difference at Dunkirk, operating under the cover of darkness.

[Northmoor]

39 minutes ago, PhilJ W said:

Just to think if the Hovercraft had been invented twenty years earlier (late 30's) it could have made a great difference at Dunkirk, operating under the cover of darkness.

Or indeed the helicopter......

[AlfaZagato]

2 hours ago, Northmoor said:

Or indeed the helicopter......

Helicopters have been around since the late 20's.   The Luftwaffe had small numbers of multiple designs in service.    I think the first trans-channel flight of a helicopter was September 1945.

[rockershovel]

3 hours ago, PhilJ W said:

Just to think if the Hovercraft had been invented twenty years earlier (late 30's) it could have made a great difference at Dunkirk, operating under the cover of darkness.

 

Ever travel on Hoverspeed? The uproar and spray made no difference to day or night!