41 years and counting.....

[BernardTPM]

Nobody's mentioned the Blue Pullmans yet...

Again, passenger accomodation in the ends, so not really 'locomotives'.

 

On the other hand, quick running engines with electric transmission and streamlined style ends.

[BernardTPM]

The first EMC Zephyr trains were delivered in the early 30's, I'd put them in the gene pool too.

Some similarities, but I don't think they used a loco both ends.

Armstrong-Whitworth built some articulated sets pre-war too, for export, that had a 'power car' of sorts.

[Nearholmer]

When I get an hour later, I need to look at whether any of the US ones had a power car at each end, my (sometimes unreliable) memory tells me not. Getting the dynamics of power both ends must have taken a bit of thought.

[Peter Kazmierczak]

Back 36 years from my original photo; a similar viewpoint.

 

 

For number crunchers it's the 10.10 ex-Cardiff formed 43040, 41041, 41042, 40017, 42060, 42061, 42062, 44020, 43041.

[brack]

The average man on the street mightn't know the difference between an HST and a MK4/91 set, but he'll be able to tell it apart from a voyager - only one smells like poo, has the seat reservation system broken and isn't long enough so people are stood up everywhere.

[The Johnster]

Running on electric, the new trains will have same the same top speed of 125 mph, but with faster acceleration.

They are designed for 140 mph running on electric power, if and when the signalling system is fitted and that is approved.

 

The requirements for running on diesel were down specified from the original IEP specification, once electrification of the GWML had been announced and following the change from power car mounted diesel power plants to smaller underfloor engines.

 

The blame for the shortfall in timings, compared with the current HST's, lies squarely with NR's inability to deliver the electrification programme as planned....and the DafT's continued bungling.

Hopefully as electrification extends out, the situation will improve and I'm sure we all hope there'll be a future decision to continue the programme as originally envisioned...and beyond.

 

 

 

 

I'm not sure about the "average man on the street" as I'm sure the average person just sees a train as just a train.

Regular travellers and commuters will probably know the difference between the faster HST and other slower MU's.

 

Personally, as much as I love them, the HST does look rather dated these days.

 

From recollection of my previous trips in Mk3's, I remember the ride was good and it was comfortable, but a long way back I vaguely recall uncomfortable seats, which may have been on Mk3's.

I don't get to travel in them these days, but I travelled in 2 GWR HST's earlier this year.

The first I was unlucky as there seemed to be a wheel flat at one end and the noise was very irritating.

The second I was even more unlucky as there was a speed related banging noise coming from the end of my carriage again.

Seating was slightly cramped and seat padding on the thin side of things (like many other trains these days).

I assume these were the tombstone seats that various people moan about?

 

 

 

 

BR were certainly not the first with such a configuration.

Various examples had been running in other countries in previous decades.

e.g. the DB VT 11.5 Trans Europe Express trains.

 

 

.

 

 

I'm not convinced that the new trains will have better acceleration than the original HST Valenta setup geared as it was.  The current refurbished HSTs are not as fast as that (though they are quieter, more reliable, and can achieve better emissions performances), so we will not be directly comparing like for like.  The IEP is a slightly different concept, with traction motors spread beneath the passenger vehicles rather than a pair of fast, powerful locomotives fore and aft, and the power to weight ratios, especially on the hybrid sets, will be very different.  Lumping a load of dead diesel equipment and it's fuel/coolant around is going to take the edge off the performance under the wires, and I would be willing to bet that a hybrid IEP set will not be able to match a Valenta HST in straight off the line acceleration.  

 

Moreover, the hybrid sets are to use diesel power west of Cardiff or Bristol, and here the situation will be reversed as an underpowered diesel train geared high for fast running has to cart a load of dead electric gear, and how this will affect timings on the South Devon banks, or Skewen and Stormy for that matter, is something else that is yet a matter for debate.  We've been here before, not very successfully, with the Adalantes, and they didn't have dead electric stuff to lug about.  A Valenta HST could easily make 90mph, the line speed, from a standing start on the down platform at Bridgend, in fact having to shut off to maintain the 50mph speed limit over the river bridge at the bottom of the bank;  I will show my arse on Queen Street if a hybrid IEP ever does this!

 

It is, of course, oversimplifying the issue to bring it down to top speeds, bank climbing, and power to weight ratios.  The IEPs have other advantages; they are quieter, have more seats per train length to put paying bums on, and more legroom for any of those paying bums that have paying legs attached.  They have the capability to be greener, but this is dependent on the emissions performance at power stations of course.  The gangway connections are much larger and more passenger friendly, which will make moving about inside the train, even with luggage (especially with luggage) much easier.  Availability should be higher and running costs lower, as should wear and tear on track.  We are promised refreshments at all seats.

 

I cannot see the 140mph capability being used on GW services in any foreseeable future, as long as 'conventional' signalling remains in use for any traffic on the line.  And I would be amazed if the hybrid sets are capable of it even on electric power!

Edited October 5, 2017 by The Johnster

[jjb1970]

Some similarities, but I don't think they used a loco both ends.

Armstrong-Whitworth built some articulated sets pre-war too, for export, that had a 'power car' of sorts.

Not the double power cars, and EMC went for articulated coaches on the Pioneer Zephyr so there were major differences. However, the concept of a lightweight high speed passenger train with a diesel locomotive/power car and designing the train as an integrated unit rather than a collection of separate locomotives and coaches was very much part of the lineage of trains like the HST I think.

[Nearholmer]

I'm still thinking that the 1935 lyntog was the most directly similar of the pre-war trains, although it was articulated.

 

Anyway, the "dieselheads" among us will enjoy this https://m.youtube.com/watch?v=Sbq7Im0g_Lw

 

These trains were in daily operation until 1973, a 38 year life, so not quite HST longevity, but astonishingly good for an early-ish design, and clocked 100mph in service.

Edited October 5, 2017 by Nearholmer

[JohnR]

The HST was arguably the train which saved British Rail, and it is not easy to fully appreciate nowadays what a fantastic achievement it was.  Developed as a reaction to the APT programme, which was ultimately a failure 

 

 

I think its hardly likely it was developed as a reaction to APT - that programme started in January 1969 - Terry Miller started the High Speed Diesel train the following year. I dont think any assumed that there would be mass electrification of the GWML, ECML, MML etc before APT went into production..... so it was natural that an alternative was developed for those line. 

[45125]

I'm not convinced that the new trains will have better acceleration than the original HST Valenta setup geared as it was.  The current refurbished HSTs are not as fast as that (though they are quieter, more reliable, and can achieve better emissions performances), so we will not be directly comparing like for like.  The IEP is a slightly different concept, with traction motors spread beneath the passenger vehicles rather than a pair of fast, powerful locomotives fore and aft, and the power to weight ratios, especially on the hybrid sets, will be very different.  Lumping a load of dead diesel equipment and it's fuel/coolant around is going to take the edge off the performance under the wires, and I would be willing to bet that a hybrid IEP set will not be able to match a Valenta HST in straight off the line acceleration.  

 

Moreover, the hybrid sets are to use diesel power west of Cardiff or Bristol, and here the situation will be reversed as an underpowered diesel train geared high for fast running has to cart a load of dead electric gear, and how this will affect timings on the South Devon banks, or Skewen and Stormy for that matter, is something else that is yet a matter for debate.  We've been here before, not very successfully, with the Adalantes, and they didn't have dead electric stuff to lug about.  A Valenta HST could easily make 90mph, the line speed, from a standing start on the down platform at Bridgend, in fact having to shut off to maintain the 50mph speed limit over the river bridge at the bottom of the bank;  I will show my arse on Queen Street if a hybrid IEP ever does this!

 

It is, of course, oversimplifying the issue to bring it down to top speeds, bank climbing, and power to weight ratios.  The IEPs have other advantages; they are quieter, have more seats per train length to put paying bums on, and more legroom for any of those paying bums that have paying legs attached.  They have the capability to be greener, but this is dependent on the emissions performance at power stations of course.  The gangway connections are much larger and more passenger friendly, which will make moving about inside the train, even with luggage (especially with luggage) much easier.  Availability should be higher and running costs lower, as should wear and tear on track.  We are promised refreshments at all seats.

 

I cannot see the 140mph capability being used on GW services in any foreseeable future, as long as 'conventional' signalling remains in use for any traffic on the line.  And I would be amazed if the hybrid sets are capable of it even on electric power!

 

Which version of the MTU repower are you compering?. The Great Western ones are set up slightly different to East Coast, XC and GC versions. Because these versions are quicker than a Valenta powered power car.

Edited October 6, 2017 by 45125

[Coryton]

When I get an hour later, I need to look at whether any of the US ones had a power car at each end, my (sometimes unreliable) memory tells me not. Getting the dynamics of power both ends must have taken a bit of thought.

 

I don't recall any that did.

 

Generally the whole train was turned at each end.

[Nearholmer]

Well, I've delved into my US and German books.

 

I can't find any US pre-war trains with 'power car at each end' configuration, and they gave up the articulated power car very quickly, moving on to lightweight (by their standards!) cars hauled by locos.

 

Both the DH and DE Fliegender Hamburger did have power cars at each end, but they had the whole power unit, engine and transmission, mounted on a power bogie, rather like the much earlier McKeen cars in the US.

 

So ...... back to Lyntog. It seems to be one of those very influential trains, the importance of which is overlooked outside its own country.

 

A few years ago, the preserved Hamburger and Lyntog were exhibited together. Perhaps someone should fix for them to be lined up with an HST, and, for completeness and a bit of a laugh, a Hastings unit.

 

Kevin

[Davexoc]

However, BR were making so much money, thanks to their new HST services, they didn't care, just built the swap out into the maintnence schedule.

They cared enough that 4 WR power cars were trialled with Mirlees engines in the 80s. Unsuccessfully mind you...

 

Dave

[Coryton]

So ...... back to Lyntog. It seems to be one of those very influential trains, the importance of which is overlooked outside its own country.

 

 

I suspect the HST layout came more from logic than influence from anywhere else.

 

If you want a streamlined train I don't think you want a loco that runs round the train at the ends (yes double-streamlined locos have been done, but don't you get a lot of air resistance in the gap between the rear of the loco and the first carriage?) And of course unit trains have other advantages.

 

So you need either a locomotive + DVT or two locomotives.

 

It wasn't practical to provide enough power with a single prime mover.

 

So why build a twin-engined locomotive for one end (which means if either engine fails the whole locomotive is out of service) and a DVT for the other, rather than identical single engined locomotives at each end?

 

(Of course in those days a DVT could have been used for passenger space, which they didn't try with the HST power cars - possibly a lesson learnt from the Blue Pullmans but probably just that a fair amount of luggage/parcels space was required and the power cars were the logical place to put it).

[big jim]

Having driven over 300 miles yesterday on the NMT it certainly gets the 'normals' looking when you pass by compared to when you are on something like a 37 which normally just gets the 'spotters' looking

[Talltim]

Weren't the guards' spaces in the power cars too noisy for them, definitely not suitable for passengers.

One thing that never seems to get a mention with the move from locos/end power cars to a diesel lump under each car is that it makes stations very noisy. It's impossible to hear the announcements at Sheffield with 20 QSK19s and various sprinter and pacer power units idling in close proximity. It was so much easier when the noise was down at the extremities of the platforms.

Having driven over 300 miles yesterday on the NMT it certainly gets the 'normals' looking when you pass by compared to when you are on something like a 37 which normally just gets the 'spotters' looking

That's cos they don't see a flying banana every day Edited October 6, 2017 by Talltim

[Nearholmer]

Coryton

 

I'm not suggesting that, when faced with a need for faster trains, the BR team said "Hey, let's copy a thirty plus year old danish design!".

 

What I am saying is that lyntog conclusively proved a design concept: DE power car at each end, with the engine mounted in the car body, and that that concept was well-established throughout Europe by the mid-60s.

 

What HST did was to increment the concept, as in bigger and faster.

 

Once the engines got to the size needed for 125mph with the train length needed, having no passenger accommodation in the power car was a foregone conclusion. Experience elsewhere gave a strong pointer that it was very difficult to get the sound proofing and ride-quality right for passengers in a power car anyway.

 

What is interesting is that the HST team didn't go for articulated coaches. That was a very conservative decision, presumably driven by the need to get the thing into traffic quickly, with minimal testing.

 

Kevin

Edited October 6, 2017 by Nearholmer

[Coryton]

Once the engines got to the size needed for 125mph with the train length needed, having no passenger accommodation in the power car was a foregone conclusion. Experience elsewhere gave a strong pointer that it was very difficult to get the sound proofing and ride-quality right for passengers in a power car anyway.

 

What is interesting is that the HST team didn't go for articulated coaches. That was a very conservative decision, presumably driven by the need to get the thing into traffic quickly, with minimal testing.

 

Kevin

 

And indeed the power car environment turned out to be so bad that the guards didn't want to put up with it either. 

 

If I recall correctly the Mk 3 design was already in progress as the next generation of coaches and the HST used them, rather than starting something from scratch as an HST trailer car.

 

Also, as you say the HST was a deliberately conservative concept, engineering not research led and the only recent experience with articulation in the UK was in the APT project.

 

It's probably a good thing that they didn't go for articulation as it's made it much easier to move redundant loco hauled Mk3's to HST.

 

Unless the WCML had gone for some kind of high speed quad-art style arrangement with its Mk 3s....

[D854_Tiger]

Which version of the MTU repower are you compering?. The Great Western ones are set up slightly different to East Coast, XC and GC versions. Because these versions are quicker than a Valenta powered power car.

 

There was a debate in the class 800 thread about the relative power to weight ratios of the new IEP running on diesel compared to existing trains and I think these are the final figures that were arrived at.

 

All figures are for five car except the HST (2+8)

 

class 800 - weight 295 tons - 2250 bhp -   7.6 bhp per ton

 

class 802 - weight 295 tons - 2820 bhp -   9.5 bhp per ton

 

class 43   - weight 416 tons - 4500 bhp = 10.81 bhp per ton

 

class 221 - weight 278 tons- 3500 bhp = 12.58 bhp per ton

 

class 180 - weight 248 tons - 3500 bhp = 14.11 bhp per ton

 

 

It should be noted that the GW class 800 will now be delivered with the uprated class 802 engine configuration placing them pretty close to a HST performance.

 

Though I'm guessing nowhere near close to the new super HST sets (2+5) going to Scotland and Cornwall.

 

P.S. Virgin operated 2+5 HST during Operation Princess and they were like proverbial off a shovel.

[The Stationmaster]

I think its hardly likely it was developed as a reaction to APT - that programme started in January 1969 - Terry Miller started the High Speed Diesel train the following year. I dont think any assumed that there would be mass electrification of the GWML, ECML, MML etc before APT went into production..... so it was natural that an alternative was developed for those line. 

 

Much nearer the truth I think.  The story is that Terry Miller and others were convinced that they could develop a conventional train offering almost as much performance as the APT without all the fancy engineering involved in the APT and with better fuel consumption (diesel instead of gas turbine) so they duly set out to get authority and were given permission to get ahead - probably the Board decided it would be wise to have a backstop if the radical design of of the APT didn't live up to its promises.

 

As it turned out it was a wise decision - the only viable way of running an APT was to make it electric which effectively meant it would only run on the WCML while the HST could be used, albeit with various infrastructure changes, on any route.    PT development wasn't really a dead end but it was hampered by various constraints - such as the pantograph problem which resulted a train of two halves while it was in my view far more akin to aircraft technology rather that the sort of tough construction needed for every day high mileage passenger train working in Britain.

 

Not articulating the coaches probably made a lot of sense in the context of the time as the Mk3 was a really a new passenger coach that could be used on any suitable route and handled in existing depots with no extensive new kit - don't forget that the only way you can lift articulated vehicles off their bogies is, ideally, to lift them all at once, which needs a whole train length's worth of interlinked jacks = even more dumped on the project costs.  They can also be harder to rerail or, more importantly swap out a vehicle for repairs etc.

 

As trains I love 'em and was fortunate to spend getting on for 20 years commuting on them with the added advantage that for a good part of that time the the WR had (arguably?) the best maintained main running line permanent way on BR.  But even in early days the ride over the bogies was never as good as in the centre of the vehicles and this is even more noticeable nowadays plus occasional wheelflats have become much more common notwithstanding the braking system.

 

Incidentally I wholly agree regarding the 132mph maximum speed with full size wheels.  When we were planning the record breaking 'Top of the Pops' run to Bristol in 1985 consideration was given to increasing the speed but technical advice was that the job would be too complicated - hence the decision to reduce the train to 5 cars in order to improve acceleration and get achievable speeds much more closely aligned with permitted linespeeds where acceleration was needed off lower speed sections.  We also made special arrangements on both the Bristol and Cardiff runs to get round some of the signalling related restrictions of speed by devising special procedures for that purpose.  It would be interesting to see if a Class 800 could beat the Paddington - Bristol record we established in that year?

[big jim]

i can certainly vouch that a 2+5 accelerates like the proverbial s*it of a shovel, last night for example, left the down holding siding in crewe, cleared the points, opened up from 25mph at the south ramp of platform 5 and was going 50 at the north end

 

similarly the 2nd run he had me straight out onto the fast north of the station, once clear of the 20 points i hit 100mph in just under 3 miles

[BernardTPM]

Here's one of Armstrong Whitworth's pre-war diesel electric trainsets (this one for Brazil in 1934). They also built twin 'powerhouses' that worked with what were basically EMUs and locomotives, including one 800hp unit that worked in the UK. All these used Sulzer design engines. They also built quite a few diesel railcars using a more compact Saurer design engine, including some for India that had quite strikingly raked cab ends. Taking all these elements together a pre-war HST might have been feasible (OK 90mph, not 125), as I outlined here. Four throbbing Sulzers... but no A4s!

[Nearholmer]

Bernard

 

I do like your pre-war HST, I really do.

 

Only one question: could it have been done within the UK loading gauge? A big issue for big engines at that date was their height.

 

Kevin

 

[Edit: I can now see that the answer is "yes, it would". And, if you split it to put 1600hp at each end of the train, it would be even closer to an HST, and the lyntog that I keep banging on about.]

Edited October 6, 2017 by Nearholmer

[jjb1970]

By the early 1930's diesel powered trains were already demonstrating their potential and it should have been clear that the days of steam locomotives would soon draw to a close. By the late 1930's companies like EMC were demonstrating the superiority of diesel trains yet even at that point there were still many steam engineers and operators living in denial and confidently predicting that steam was superior for many applications and that steam would co-exist with diesels for the long term. And that is before considering electrification.

[kernowtim]

40 years ago I picked up this catalogue from my local toy and model shop,cost me 25p. About 3 years later I got a 3 car set for Christmas,eventually expanded to 8, which I still have ,although the original motor died many years ago.

I always take the time to admire the fgw examples running locally,even if they do sound wrong!!