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Imaginary Locomotives


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More likely that Woodhead would have been converted to AC and perhaps the 77s would have survived to be converted to AC. I wonder how different they would have looked with a transformer, rectifier, and braking resistors squeezed in! No AC regenerative braking in those days.

I think if Woodhead had been converted to AC, most likely either better utilisation of the existing AC fleet would have rendered the 76/77's redundant anyway, or a further batch of class 87's would have been built.

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I think if Woodhead had been converted to AC, most likely either better utilisation of the existing AC fleet would have rendered the 76/77's redundant anyway, or a further batch of class 87's would have been built.

Retention of the 85s when the 90s were introduced maybe rather than their rapid destruction?

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Retention of the 85s when the 90s were introduced maybe rather than their rapid destruction?

It would depend when the AC conversion was done.

 

The 87s were introduced to provide sufficient locos to cover extension of services over Weaver Junction - Carlisle.  The 90s were built to allow a cascade of 86s onto lesser duties, so 81s/85s could have been useful over Woodhead where a reluctance to allow them to run at 100mph wouldn't have mattered.

 

Oh how this country could have done with a rolling electrification scheme after 1974!  

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It would depend when the AC conversion was done.

 

The 87s were introduced to provide sufficient locos to cover extension of services over Weaver Junction - Carlisle. The 90s were built to allow a cascade of 86s onto lesser duties, so 81s/85s could have been useful over Woodhead where a reluctance to allow them to run at 100mph wouldn't have mattered.

 

Oh how this country could have done with a rolling electrification scheme after 1974!

This country could do with a rolling programme of many things, but that requires an ability to think and plan over a length of time greater than the term of office of a politician.

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It would depend when the AC conversion was done.

 

The 87s were introduced to provide sufficient locos to cover extension of services over Weaver Junction - Carlisle.  The 90s were built to allow a cascade of 86s onto lesser duties, so 81s/85s could have been useful over Woodhead where a reluctance to allow them to run at 100mph wouldn't have mattered.

 

Oh how this country could have done with a rolling electrification scheme after 1974!  

 

Actually it could have done with it after 1964!

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This country could do with a rolling programme of many things, but that requires an ability to think and plan over a length of time greater than the term of office of a politician.

Can't think of a way to do this and retain democratic accountable government, though.  The desirability of democratic and accountable government is another matter altogether, and not a discussion I wish to be involved in...

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Might have happened if DC went all the way to Liverpool via CLC and somewhere a bit further East - might have needed a few more locos with 1500V DC...

 

...or perhaps a fleet with dual voltage capability for through working on AC routes. I fancy seeing something in a 87 style perhaps a bit longer with two pantographs, perhaps with triple axle bogies for good measure to save double heading.

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Might have happened if DC went all the way to Liverpool via CLC and somewhere a bit further East - might have needed a few more locos with 1500V DC...

 

...or perhaps a fleet with dual voltage capability for through working on AC routes. I fancy seeing something in a 87 style perhaps a bit longer with two pantographs, perhaps with triple axle bogies for good measure to save double heading.

Sounds like the true calling for the class 89 to me... or maybe the originally intended style of class 88 for something different?

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Real fantasy stuff now-1500v DC is extended up the GC to Marylebone, and, with a fleet of multi voltage class 77's, through electric working to the south coast begins in 1960.

 

With the opening of the channel tunnel in 1967, through trains to Paris and Brussels starts, along with freight and overnight trains to many European destinations. SNCF BB7200 locos equipped with shoegear become a familiar sight as far north as Leicester Central, and triple voltage class 86's appear in Paris, Brussels and occasionally Amsterdam.

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Can't think of a way to do this and retain democratic accountable government, though. The desirability of democratic and accountable government is another matter altogether, and not a discussion I wish to be involved in...

Many of our neighbors manage to have a rolling programme of electrification without considering it a threat to democracy.

An incoming government could just can it, but presumably such a policy would be considered a vote loser. So they don't.

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7 minutes ago, scots region said:

Question for you all, does a wider gauge mean a reduction in the sloshing or surging effect experience by large tank engines, or is an absolute? 

Control of the sloshing or surging by internal baffles in the tanks will have far more bearing on the effect than relatively small gauge changes. Big tank engines run on 800mm and metre gauge.

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20 minutes ago, scots region said:

Question for you all, does a wider gauge mean a reduction in the sloshing or surging effect experience by large tank engines, or is an absolute? 

 

ScR

 

Surely that's more of a fore-and-aft issue than a waggle question - so has to do with the unbalanced reciprocal forces resulting in a surging motion generally. Three cylinders is the way forward, as Stanier understood with the 3-cylinder 2-6-4Ts built for the Tilbury section.

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29 minutes ago, scots region said:

Question for you all, does a wider gauge mean a reduction in the sloshing or surging effect experience by large tank engines, or is an absolute? 

 

ScR

I can see why you ask. You would think that a narrower gauge would mean more overhang, therefore more of a tendency to "crab" down the track. I guess if you take it to it's extremes, and put big fat tanks on a standard gauge loco, then ran it on 600mm gauge track, then maybe there would be more of a sloshing surging effect, as more of the weight would be outboard of the centreline or balance point of the engine. For the most part though, as above, the surging of water in the tanks would impart a fore & aft motion to the engine, rather than a side to side motion. I suppose if the tanks were across the engine, then there might be a side to side motion, especially going round curves.

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27 minutes ago, rodent279 said:

I can see why you ask. You would think that a narrower gauge would mean more overhang, therefore more of a tendency to "crab" down the track. I guess if you take it to it's extremes, and put big fat tanks on a standard gauge loco, then ran it on 600mm gauge track, then maybe there would be more of a sloshing surging effect, as more of the weight would be outboard of the centreline or balance point of the engine. For the most part though, as above, the surging of water in the tanks would impart a fore & aft motion to the engine, rather than a side to side motion. I suppose if the tanks were across the engine, then there might be a side to side motion, especially going round curves.

 

More to the point, narrow gauge engines tend to be slow. The Davies, Metcalfe 2-6-2T at the VoR are 25 tons, over 8’ wide on 2’ gauge and have tanks which completely conceal the boiler, but they seem to manage well enough. 

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46 minutes ago, rockershovel said:

 

More to the point, narrow gauge engines tend to be slow. The Davies, Metcalfe 2-6-2T at the VoR are 25 tons, over 8’ wide on 2’ gauge and have tanks which completely conceal the boiler, but they seem to manage well enough. 

Didn't realise they were 8ft wide! That's almost standard gauge width.

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It wouldn't be doing any harm!  The wider the gauge, the lower the centre of gravity will be for an engine of otherwise similar dimensions and proportions; I suppose you would compare the UTA WT 2-6-4Ts to the mainland Fowler locos.

 

The problem is held to be the major factor in the Sevenoaks derailment in 1927, but identical locomotives were trialled at over 80mph on the Great Northern section of the ECML and found to run perfectly satisfactorily; Gresley, who was on the footplate, said as much, and these were 3 cylinder locos to boot.  The Southern had already decided within hours of the accident that the locos were unsafe and rebuilt them as 2-6-0 tender locos, though, and never built another 2-6-4 tank loco.  LMS designed 2-6-4Ts were built for the Southern Region and used on fast trains after nationalisation, and the BR standard version of the design was designed and built at Brighton; none of these locos ever gave any trouble with ride quality.

 

It may be that the Sevenoaks derailment was more to do with poor track conditions rather than an unstable loco, but this is ground that has been covered before by people more knowledgeable than me.  

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6 hours ago, The Johnster said:

It wouldn't be doing any harm!  The wider the gauge, the lower the centre of gravity will be for an engine of otherwise similar dimensions and proportions; I suppose you would compare the UTA WT 2-6-4Ts to the mainland Fowler locos.

 

The problem is held to be the major factor in the Sevenoaks derailment in 1927, but identical locomotives were trialled at over 80mph on the Great Northern section of the ECML and found to run perfectly satisfactorily; Gresley, who was on the footplate, said as much, and these were 3 cylinder locos to boot.  The Southern had already decided within hours of the accident that the locos were unsafe and rebuilt them as 2-6-0 tender locos, though, and never built another 2-6-4 tank loco.  LMS designed 2-6-4Ts were built for the Southern Region and used on fast trains after nationalisation, and the BR standard version of the design was designed and built at Brighton; none of these locos ever gave any trouble with ride quality.

 

It may be that the Sevenoaks derailment was more to do with poor track conditions rather than an unstable loco, but this is ground that has been covered before by people more knowledgeable than me.  

Hi Johnster,

 

All of the 2-6-2 and 2-6-4 tanks that I have ever ridden have a much more stable ride than the 2-6-0 tender versions of the same irrespective of tank ullage. The most unstable ride as far as 2-6-0 types are concerned was the Crab 42765 at Bury which was very lively at certain speeds.

All locomotives with side control trucks at each end need to have differential arrangements so as not to induce oscillations. In the case of LMS/BR 2-6-4 tanks this is via different spring rates due to the different axle loadings of the trucks, in the case of the LMS/BR 2-6-2 tanks the leading truck is sprung and the trailing truck is of the swing link type.

 

I'm not sure of the the Sevenoaks derailment but there was on derailment on the Southern involving a tank engine where the track was blamed for it was ballasted with the rounded shingle pebbles from Romney Marsh compounded by the ratio of the links of the swing link truck.

 

Gibbo.

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10 hours ago, scots region said:

I was watching some footage of UTA workings in the 1960s and saw the ex-NCC WTs get up to quite some speed, so I wondered if the Irish gauge was helping in that regard.

 

A WT is this 

 

NCC_WT_Class_loco_no_4.JPG

Their standard gauge cousins, LMS and BR 2-6-4Ts were all highly regarded for their ability to get along when required, plenty of reports of 80mph + on longer runs. Good exemplars of the old saw: 'if it looks right, it is right'.

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11 hours ago, The Johnster said:

It wouldn't be doing any harm!  The wider the gauge, the lower the centre of gravity will be for an engine of otherwise similar dimensions and proportions; I suppose you would compare the UTA WT 2-6-4Ts to the mainland Fowler locos.

 

The problem is held to be the major factor in the Sevenoaks derailment in 1927, but identical locomotives were trialled at over 80mph on the Great Northern section of the ECML and found to run perfectly satisfactorily; Gresley, who was on the footplate, said as much, and these were 3 cylinder locos to boot.  The Southern had already decided within hours of the accident that the locos were unsafe and rebuilt them as 2-6-0 tender locos, though, and never built another 2-6-4 tank loco.  LMS designed 2-6-4Ts were built for the Southern Region and used on fast trains after nationalisation, and the BR standard version of the design was designed and built at Brighton; none of these locos ever gave any trouble with ride quality.

 

It may be that the Sevenoaks derailment was more to do with poor track conditions rather than an unstable loco, but this is ground that has been covered before by people more knowledgeable than me.  

It's not correct that the Southern never built another 2-6-4T, the W Class was introduced in 1931. However, they were not generally used for passenger service (and trials showed them to be very rough riding) - source SEMG. Apparently the trials were between Tonbridge and Ashford and Victoria and Tunbridge Wells West in 1948.

 

 

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