BR / BTC came very close to having class thirty eights. You can trace this back to the very development of the CSVT engine which was the obvious successor to the SVT even by the time the first D200s had completed commissioning.
Further the last orders for 37s were seen as being largely a freight dedicated batch and EE apparently offered the "bone" cabbed 2000hp locos they sent to east africa ( now sudan and somalia)
What form would the class 38s or class 40/1s have taken though ?
This is a fascinating flight of fancy in fact. There are several possibilities.
Firstly the earliest solution would have been a production run of 2000hp D6700s. There may have been radiator modifications, perhaps a higher capacity boiler. One option EE may have taken up though could have been dual heat with a boiler space and space for a straight six 450 hp auxiallry motor ( a duplicaiton of the boiler / Engine space as penned in the sales panphlet to BR for D6700) . This would have needed more legnth to fit the additional equipment and allow for longer range fuel tanks. Weight would have then pushed up about 6-8 tonnes for the frame and tanks and 2 tonnes for the engine : thus making an RA6 loco. EE would have kept the proven deltic/D6700 gearing although fitted cast bogie frames and stronger armature equipment to tackle the extra thrashing.
EE also offered the v16 CSVT at the then "safe" 2350hp rail de-rating, approximately the same as the D6700 as lowered from marine / power station rating per cylinder. This rating ended up in the successful C1800s of Portuguese railways. Brush were also in the picture here as locomotive manufacturer! This before the class 31 type was re-engined with the 1470hp SVT version of the v12.
There were several precedents for brush being asked in: one they had produced a 2000hp class 31 with a air charge cooled Mirlees unit, and they had worked on peaks by that time in the very early 60s. The other being that BTC/BRB did want a degree of standardisation but wanted some wider perespective in delivery-solution and not being too bound to one supplier.
However neither were to be, and it took EE making DP2 and BRCW's Lion to move things forward for more modern, lighter weight type 4s to start appearing in production by the mid 1960s.
By then EE had more experience of the CSVT engine and were confident that the then full marine rating was just as applicable to rail traction. It wasn't long after D449 was delivered that the RK engine gained over 3000 hp for marine application and went on to 3250 and more in the mid seventies.
So EE offered the 2000hp in the "east african railways" design, probably with ETH as an option. However BRB declined and stayed with the same strategy as the D200 order- it is standard as a class by numbers now, don't fix if it aint broken.
Type 3s and the newly ruston re-engined almost type 3 Brush type 2, were proving themselves to be very useful: tackling especially freight diagrams previously larger or multiple steam locos were seen on, and also taking over the diagrams of mid powered steamers like the black 5 and castles in generally excellent fashion.
Meanwhile the type two investment showed itself already to be a folly because the underpowered "rats" were often needed paired up to work even 300 ton trains and the single unit traffic they had been built to command, was drying up post Beechings and the rise of the lorry and motorway. There are enough "standard gauge" railways in the world at that time for the standard LDA6 loco fleet to have been decimated down by sale to needy railways with less ambitious speeds and a requirement for low gross weight of locos over poorer trackbeds and bridging. Some of the "rat" classes should have been upgraded to the far superior LDA 8 engine as type threes to join their more successful cousins as type 3s, which became the Class 33.
350 to 1000 tonne freight was where the railway excelled and on the passenger side, the intercity and express cross country and commuting services were also the economic area the railway could win in, and these diagrams remain so today and will become more so in future . Type 3s could command the lower end of this tonnage in single units, and the larger end would prove to be economic for a long time as double units until the advent of SEPEX and the american creep control systems enabling single units to start 1000 tonne plus trains.
So in 1964 to 65 the BRB could have decided to take up EE's offer for a 2000hp 12 CSVT based, slab end loco. However rather than being a substitute for the last 40 or so D6700s, an order for a new loco class, to be the "little sister" to the then planned EE type 4 production run from the success of DP2. What form then a "syphon Super G!" ??
Well by then the order for a new class would have been with slab ends but most likely with internal walk through for driver safety and inspection "on platform" of internal mechanism failures. An extended order of D6600s to 2000hp with ETH fitting could have been another tantalising possibility. However there was also a dwindeling number of RA5 lines. Perhaps a new 2000hp loco would have been given higher weight and for freight dedication, a lower gearing like the 20s and later CP7 bogies?
I like to think that an EE super-syphon would have been in effect a mini fifty with pleasing tumble home sides. It would have probably retained blue star, buffer level multiple working and hence, as the original d400, with an elegant roof level horn box and route indicator below cab window. Thus it may have resembled a cross between the D400 and the shorter, lighter C1800 exported to Portugal.
What gap in the haulage requirements of the mid to late 60s would this loco have filled ? Well given a full dual heated, stretched RA6 variant then it could have been employed on the then rather common expresses to reginional cities and towns from the then partly electrified WCML which were then served in the early 60s still by steam, d200s and peaks: the latter being total overkill for hauling load 6 to 8 on a 40 to 70mph route. The first generation DMUs were already proving troublesome on trans penine and other express and semi fast services so there was another chance to displace these to their rightful place on regional stopping services. Other diagrams and routes for an ETH / dual heat class could have been cross london with Southern region stock, and dragging southern region units around like 33/1s but maybe on routes like the MULE or as above, cross london or SE to SW services.
A 2000hp loco at RA5 with ETH and standard gearing would have as an alternative, been a very useful bit of kit replacing for example type two double headers on ex WCML route5 s to Aberystwyth and the WHL. We must also remember that the crown prince of passenger traction weighed in at a humble 105 tonnes, the supreme Deltic. Light weight was seen as the key to good power to weight delivery and high speed by EE despite the tendency to wheel spin.
This is another little issue on the electrcial power delivery : EE were ready with AAA arrangement for traction motors with independent current reduction per motor as implemented on the class 50. How much use would this have been on a class 37 with even more horse power ?
The final tantalas I present is then also a matter of electro-mechanics: 1) would the locos have the KV10 style sensibility 2) would EE have dared to use a fourth field diversion to a final, higher voltage enabling 95-100mph "cruising" ? Post 1995 bashers don't believe that the humble 37 could top 100mph in single form. They would have day-in-day out on the Glasgow-Edinburgh run and in pairs on the Super west country services (replacing and supplementing Westerns). The Kv10 could have rendered the locos actually more reliable or with a cheaper service because in theory it reduces driver demanded overloads and hence wheel slip. At the same time it would have deminished the real strong point of 37s- being able to groan up gradients on high amps at decreasing speed.
The one over riding question would be if the CSVT unit in the 1960s form should have ever gone to the rating of 167 hp per cylinder : 50s were experiencing engine block cracks in the 1980s, while 37s rode on and could have remained as a class of over 150 locos today given the traffic for them on Ra5 routes. Inherently a multiple of three , 120', is a smoother engine for an equivalent per cylinder rating because the power delivery pulses are more balanced ; this is the dub in the fifties. 37 292 was a lame machine when I had it, but was that due to the uprating or to a lack of up-rated maintainance on the valves and timing chain ? I think a fleet of 2000hp super syphons could have seen their wings clipped by dertaing to 1850 or all the way to D6700, but also they would have been standard enough, new enought and useful enough to have gone through HGR and received alternators and CP7 bogies.
In the 1970s there was no stomach in reality but for the highest performance end of freight and passenger ( HST) and the ECML was still planned to be electrified. Had we never had diesel hydraulics or so many vermin type 2 sulzer slugs then there would have been an obvious gap for a light type 3 / 4: Sulzer offered the v8 version of the LDV engine for example or derated v12s to various customers. Also the fuel crisis could have set the scene for the reduction of type two multiple working and the slowing of type 4 diagrams. Type 3s and the Brush 2, have all been quoted as being the best fuel economic locomotives relative to the broad duties they tackled.
At least EE fans can look back at the various machines: the ever ready 08's and 20s, the magnificent stop gap deltics which long out lived their design missive, the duplicitous 50s- soveriegn when working but flawed in original complexity and even HGR remodellign, the robust class 40 and finally the ubiquitous, all conquering class 37 : a locomotive which spanned 50 years of railway history, working the legnth of breadth of the Uk, tackling everything from the heaviest freights, the most challenging routes and even propelling the APT on speed trials on the ECML : the most renown and resolute of all classes by nature of their ability to take on more than they were designed for and to live longer than anticipated to the joy of railway fans the legnth of Blighty!!!
søndag 14. oktober 2012
søndag 30. september 2012
The 2350 bhp big sister never was on BR
It was fascinating to hear that in the race fora type four power over essentially type two double headers, that brush were also in the game with a design featuring an EE power unit.
The timing is what could be quite the crux of the whole matter: EE proposed the csvt and co-co construction be adopted for later runs of the EE type four D200. This was maybe as early as 1959 by which time ee had sold some 12CSVT locos to africa and no doubt fully evaluated the power unit at upto 2000bhp and even beyond for a marine constant output rating.
Btc/brb in their wisdom knew the d200 proved a useful design and reliable. It is still strange that they did not opt for a lighter RA6 co-co with the svt engine because bogies are life time items with probably little to gain in purchase and maintainance costs over the life of a loco. One hundred and twenty forty 'zeros' would have been a significant class in its own right by 1960. A subsequent csvt class in co co would have followed even more standardisation with the EE type 3 : bogies and many other features like cabs, noses and boilers. For a loco with no boiler space required the 16 csvt can actually be fitted into a 37, with the c1800s exported to portugal being the same weight range as the venerable 37s.
The ee outcome would have been an ra6 syphon with 100mph capability if ordered to a 1960 design, nose end and no KV10.
But what of brush?
Well in 1960 it would have no doubt been a stretched class 30, but probably without a corridor door . Incidentally the mirlees engines of the brush type 2 were not swapped out until 1964, so it is interesting that earlier cooperation was aired, probably under the proposed stipulation of standard power units being employed across manufacturers. Sulzer being swiss were expensive and left brush and btc/brb exposed to any weakness in the pound. Also as happened later, brush lacked capacity to meet demand from european railways and began using various sub contractors to build major components or even complete power units and the fiasco with the uprated 'duff' PU was somewhat inevitable.
EE rustons scaled their work well in the 1950s and had a successful expert sub contractor in Robert Stephenson and Hawthornes in derby.
A later order would have resulted in the BTC stipulated slab end lion and then hymeks and later variants. Probably with under window indicator opanels but at 2350bhp brb may have wanted multiple working with high side connection. The same fate befell the d400s rather clean initial design while the duffs escaped multiple working which would in fact have extended their utility on freight immensely and on the larger midland and west country passengers and sleepers.
What ever the body design, the design outcome of the mechanical electrcal traction gearings chosen would have fascinating. Would brush have opted their preference for high amps on a somewhat lower torque, higher rpm engine than the 12LDA they had some exposure to in the peaks by then. Or would they have opted for acheiving the same as EE, a higher voltage set up with effectively lower gearing but arguably more progressive delivery of electical power from the longer rpm range of the ruston big vee.
If this had come to be in 1960 then you could bet that brush would have made a relaible locomotive with performance better than the Peak heavy weight on expresses. There after a further uprating to 2700 hp and two or three suppliers would have made the big dubber the standatd PU and far more push back against BtC for all the prototype gadgetry emloyed in the first ten years of class 50 life.
On many types of services the non KV10 delivery or higher amps a brush loco may have employed, the locos at the 2350 hp would have given the class 50 more than a run for their money head-to-head, and tackled freights better at low speed and gradients due to the over caution excised by the kv10 controller. Furthermore as with the 37s, 31and C 1800s of portugal, the reliability would have been far better than either the EE dubbers or the Brush sulzer duffers which came to pass into railway legend for their idiosyncracies.
tirsdag 6. mars 2012
Wasted Youth?
I often think what a waste of time all that running about after locos was. Then i remember a big loco dropping on and a desperate bail for it.
One i always come back to was on my first freedom-of-scotland. July 1983. I think we were due to do the overnight anyhows to be able to cover some super early glasgow moves or as it happened go further north. Anyway if I remember right there were a couple of 40s ganging about ecs and the 22 something edinburgh mail. We got the gen that a duff had a windscreen smashed. The 2345 1N05 was going to be late.
David baker and perhaps peter walker were on board mo less than a whistler. 40 170 had 'produced'.
Just a few year earlier not an eye lid would have batted at a forty on this train, but now 40s were no longer allocated on ScR. Duffs reigned on all expresses just about. And 40s were, like the big sister deltics, for the cutting torch. Generally more reliable than duffs and peaks, their charming chortle was not enough to save them even by a rationalisation. To be withdrawn upon failure pretty much.
My point being it was darn exciting to get this 133 tonnes of whistling, grumbling EE music on the service. Probably the second forty i ever did, having been the only basher on 40001 on the carlisle newcastle that week.
At gleneagles the infamous bradford bender and gang came shreaking on board and infected us with their mad west yorkshire enthusiasm for the old girls.
At some point at night there was so me banter about queen street control or some other BR digniatries had accused rail enthusiasts of bricking the duff. Bradford and co had been on the shed that day. I suppose 40 170 was xo so not popular despite it being a mildish july night. Anyway it became an instant platform myth.
The truth is the forty lacked a window too. David baker had a rotten run up to perth with a broken 2nd mans cab side window. Springburn 'neds' had doen a few of the locos sitting on pole position, the forty probably being allocated ecs down the tunnel. In fact i think it banked out the 1650 ft bill.
So back to my point, loco type aside. Was it all a misspent youth? Well yes and no of course. It taught me to be independent and positive to making new friends with like minded strangers. It taught me to be far more egalitarian, in fact pretty socialist. Most bashers I met came from terraced houses in the midlands, owned one denim jacket and one rabbit trimmed parka and spent every spare penny on bashing.
Socialism is about to be a really useful skill set as we move into economic catastrophe, having been a ridiculed political stand point why we all raan up bigger debts than under any actual socialist government.
There are downsides- it is not good for your health and there is a large amount of passiveness about being taken evverywhere on someone elses system and timetable.
Other skills you acquire though? Independence and self reliance. Communication. And above all planning, logistics and risk management in doing moves like Kilmarnock or Cærsws.
That and seeing scotland in particular from the relaxing arm chair seat that was the mark I corridor carraige of BR. That was worth it all.
The biggest of them All
Well this is the biggest of them all for me personally. Despite being a syphon basher I loved 40s too.
It was big because it was a drop: the duff had its windscreen smashed, the 40 had its second man cab side window also smashed but there were no other type 4s available ( think it ran NB ?)
40170 1N05 2330 Glasgow QS - Inverness, to Perth 26 July 1983
Bradford Bender and co came on at Gleneagles - guess they took the euston -inverness sleeper or a local service or perhaps the edingburgh portion went that way.
40170 was in great nick and gave a superb run, perhaps Peter Walker and Davey Baker in control.
It then worked the down service, piloting a 47 south as far as stirling for the QS-Waverly split at the time.
40 170 down service
It was big because it was a drop: the duff had its windscreen smashed, the 40 had its second man cab side window also smashed but there were no other type 4s available ( think it ran NB ?)
40170 1N05 2330 Glasgow QS - Inverness, to Perth 26 July 1983
Bradford Bender and co came on at Gleneagles - guess they took the euston -inverness sleeper or a local service or perhaps the edingburgh portion went that way.
40170 was in great nick and gave a superb run, perhaps Peter Walker and Davey Baker in control.
It then worked the down service, piloting a 47 south as far as stirling for the QS-Waverly split at the time.
40 170 down service
fredag 1. april 2011
Crystal Balling UK Motive Power 2012-2022
Well now you really have to put the final curtain down on the first generation production diesel electrics (c1950-1970). Be Happy! On secluded branch lines their straigth-through decibels will roar on, and you can get involved with their maintainance, maybe even retrain as a driver!
Now the second generation 1970s locos are coming to their swan song too, with re-engining and rationalisation of classes now the way forward.
\
So what do I predict in my crystal ball? Will we see a new type three?
The way forward is the old-new way. Trams, zings, call IC125 power cars what you like they saved the credibility of the railway through the 70s and 80s and floated GWRs boat in the 1990s and 00s. Now they are in their swansong, with new power-units. The next thing I predict here is that either class 92s will be hauling them "Under the wires" on the long distance routes using signigicant portions of the West and East CML's, or a dedicated power car being made to be dragged around the extremities and the western region. A move towards a "Unit" based train run with IC 125 power cars is unlilely given HST2 and the current franchise set up ( see my critique of this earlier blogg)
Dual and triple mode ( triple being over head 25kv, third rail and DEMU) multiple units will probably evolve soon in at least cross london guises. Given a real committment in some kind of public-private set up for offering better services while reducing the carbon footprint of those very trains, then this type of unit could find use in many more areas, Scotland , the NW, the branches running off the ECML and of course many cross-pennine services.
New locos? Well we will probably see the new "High" powered, of over 3600 hp and 4000 tonne plus haulage capapbilities coming onto BR; and I would dare to say that we will see the following: the oil sloshing voith maximas
which are actually not really any better than class 60s IMHO. Which brings me to the second: Class 60s with new PUs: either the GM 645 derived unit at its new higher rating, aroudn 3600hp, or the v16 RK215 at over 3600 hp at least. The latter would be the preference of the enthusiast, the former that of the accountants.
At some point we will need to see a replacement for the 57s and 67s in a lighter, better performing locomotive. This is probably some time off, and will take some major in- or de- centive to push the owners off their ageing trash!
As for our old chesnuts, the wonderful type 3s and type two and half "goils". Well this would come down to fuel economy and track access charges legitimising a lighter loco for sub 1000 tonne trains. Also on the topic of fuel economy it may become so expenisve to run locos that using the US / Canadian Robot system where extra power is only taken when needed, may see a return to multiple working. We just haven't seen the type of trains so far that can't be hauled by 66s. This would mean also a diesel-under-the-wires charge coming in so that dragging electric units to places like Lincoln and Sunderland becomes attractive: step in the dual mode train though here!
Type three was great for hauling around 500 tonne frieghts at less than 50mph or 250 to 300 tonne passenger services at up and down to 70mph. These trains still exist, and smaller, but are rare enough not to merit moving away from the EMD- GM monotomy of class 66 and 67/57.
In the future though, the gridlock and the battery car will have us more on trains and rightly so. Rolling on steel rails has always been one of the best transport systems. Don't forget that bitumen is a happy biproduct of the oil industry, and as oil starts to go dry, they will start to make more "coker" products ie broken down bitumen into smaller carbon chains including the octanes we crave. This will excaerbate the cost of driving by making the roads we drive on far more expensive to build and maintain. Road surface makes for poor recycled material, where as track can be smelted and concrete sleepers used in embankements, ships ballast and sea defences.
The new transport model will include little hire electric cars to zoom you around cities and industrial estates from rail hubs, while we will succumb to collective "dial a busses" or "taxi-shares" for many more of ventures over our own thresholds.
All this will mean far more "permanent way" building and upgrading, where a type 3 would be ideal. Also some routes like Barrow, Stranraer, Lincoln-Hull, Scarborough and so on may become more attractive for dragging el-units to, or portions of bigger route trains: a blast from the past!
Now the second generation 1970s locos are coming to their swan song too, with re-engining and rationalisation of classes now the way forward.
\
So what do I predict in my crystal ball? Will we see a new type three?
The way forward is the old-new way. Trams, zings, call IC125 power cars what you like they saved the credibility of the railway through the 70s and 80s and floated GWRs boat in the 1990s and 00s. Now they are in their swansong, with new power-units. The next thing I predict here is that either class 92s will be hauling them "Under the wires" on the long distance routes using signigicant portions of the West and East CML's, or a dedicated power car being made to be dragged around the extremities and the western region. A move towards a "Unit" based train run with IC 125 power cars is unlilely given HST2 and the current franchise set up ( see my critique of this earlier blogg)
Dual and triple mode ( triple being over head 25kv, third rail and DEMU) multiple units will probably evolve soon in at least cross london guises. Given a real committment in some kind of public-private set up for offering better services while reducing the carbon footprint of those very trains, then this type of unit could find use in many more areas, Scotland , the NW, the branches running off the ECML and of course many cross-pennine services.
New locos? Well we will probably see the new "High" powered, of over 3600 hp and 4000 tonne plus haulage capapbilities coming onto BR; and I would dare to say that we will see the following: the oil sloshing voith maximas
which are actually not really any better than class 60s IMHO. Which brings me to the second: Class 60s with new PUs: either the GM 645 derived unit at its new higher rating, aroudn 3600hp, or the v16 RK215 at over 3600 hp at least. The latter would be the preference of the enthusiast, the former that of the accountants.
At some point we will need to see a replacement for the 57s and 67s in a lighter, better performing locomotive. This is probably some time off, and will take some major in- or de- centive to push the owners off their ageing trash!
As for our old chesnuts, the wonderful type 3s and type two and half "goils". Well this would come down to fuel economy and track access charges legitimising a lighter loco for sub 1000 tonne trains. Also on the topic of fuel economy it may become so expenisve to run locos that using the US / Canadian Robot system where extra power is only taken when needed, may see a return to multiple working. We just haven't seen the type of trains so far that can't be hauled by 66s. This would mean also a diesel-under-the-wires charge coming in so that dragging electric units to places like Lincoln and Sunderland becomes attractive: step in the dual mode train though here!
Type three was great for hauling around 500 tonne frieghts at less than 50mph or 250 to 300 tonne passenger services at up and down to 70mph. These trains still exist, and smaller, but are rare enough not to merit moving away from the EMD- GM monotomy of class 66 and 67/57.
In the future though, the gridlock and the battery car will have us more on trains and rightly so. Rolling on steel rails has always been one of the best transport systems. Don't forget that bitumen is a happy biproduct of the oil industry, and as oil starts to go dry, they will start to make more "coker" products ie broken down bitumen into smaller carbon chains including the octanes we crave. This will excaerbate the cost of driving by making the roads we drive on far more expensive to build and maintain. Road surface makes for poor recycled material, where as track can be smelted and concrete sleepers used in embankements, ships ballast and sea defences.
The new transport model will include little hire electric cars to zoom you around cities and industrial estates from rail hubs, while we will succumb to collective "dial a busses" or "taxi-shares" for many more of ventures over our own thresholds.
All this will mean far more "permanent way" building and upgrading, where a type 3 would be ideal. Also some routes like Barrow, Stranraer, Lincoln-Hull, Scarborough and so on may become more attractive for dragging el-units to, or portions of bigger route trains: a blast from the past!
fredag 11. mars 2011
The Secrets of the Class 37s Success
For the "first generation" of major dieselision, there is no doubt that the EE Type 3, later class 37, was the most successful on many counts, and this is best reflected in their longevity and the usefulness the class offered into the 2000s.
The only other comparable locomotives are ....also English electric, being the venerable 08 and the class 20, although the latter is most often used in pairs, a somewhat wasteful formation both at the time to erradicated steam and later in their lives. However, they too prove to have their niches.
The main failings of the first generation type 4s were the 1CoCo1 wheel arrangement and the overall wieght. Coupled to the class 40 and 44 being underpowered for their intended duties, and the lack of reliability from the class 45, then these locos were a heavy, expensive experiment. The class 46 was reputadely a more reliable unit, as were of course the class 40s, some of which were in completely working order when cut up in 1985-6.
Of the second generation, there were only three classes eventually ordered: 35 being the first, then 47 and 50. Once again it was actually the type 3 which prove to be the most reliable and "designed for task, delivered to design" . Both the 50s and the 47s required extremely expensive refurbishment to overcome their reliability issues, and in effect the 47s in particular did not live up to their design missive.
Brush Traction then had a pragmatic approach to what was still fairly experimental machinery. They had already shown this in re-engining the problematic and underpowered type 2 AIAs, and took a sensible decision to de-rate the new type 4s after rectifiying the terrible problems with the Sulzer units. One of the key issues was most likely caused by sulzer sub contracting production of the LDA series engines out, and thus quality control at various levels was not fulfilled.
In life, however, the sulzer 12LDA twin bank engine prove easy to both rectify and "keep on top of" with regular, specific maintainance. It is a single turbo engine with otherwise good access to components and inspection points. This contrasted with its own cousin, the 12 and 16 LVAs which had "blind" spots in the crank cases which lead to catastrophic failure due to a simple locating pin tool being ill machined! The 12LDA units could be hammered back into service rapidly, and given the amount of idle service duffs seemed to get in some areas when the more powerful 56s and 8s came in or when pairs of class 37s or 31s were needed to start heavy loads the 47 couldn't cope with in its solo existence, then class availability was kept artificially high. A better measure is MPC: miles per casualty, and for the same high speed services as the 50s, the 47s faired no better in fact!
The 47's legacy really lived on because Brush won the lions share of the two next generations of locomotive orders in the class 56 and 60. The nickname "duff" has cast a long shadow in UK locomotive history.
In the mean time however, GEC had gone into Alsthom and had concentrated on mainly AC locos for mainland europe with only relatively small orders for the "prima" units, tha majority of those for France and the UK, with the rebuild of the 333s being just that. It was the USA who had kept advancing diesel loco technology in heavier RA7 + freight locomotives, and actually could offer units down to under 120 tonnes based around the GM 645 line of PUs and CoCo format.
The failure of the 56s to haul the heaviest trains in the UK, lead to the class 59 outshining all but the "tugs" when they came on the scene. Major teething problems once again with the 60s meant that in the soon-to-be private world the EMD class 66 would rule the rails. ( although as a footnote, the USA proiduced Class 70 has had its share of teething problems)
So in a way, the perpetual under-delivery by Brush and compacency by GEC Alsthom opened the gates for the very competent N.American GM-EMD to swing in. WIth the Class 60s likely to be withdrawn or rationalised, we will one day soon see the end of UK produced locomotives on British metals.
The only other comparable locomotives are ....also English electric, being the venerable 08 and the class 20, although the latter is most often used in pairs, a somewhat wasteful formation both at the time to erradicated steam and later in their lives. However, they too prove to have their niches.
The main failings of the first generation type 4s were the 1CoCo1 wheel arrangement and the overall wieght. Coupled to the class 40 and 44 being underpowered for their intended duties, and the lack of reliability from the class 45, then these locos were a heavy, expensive experiment. The class 46 was reputadely a more reliable unit, as were of course the class 40s, some of which were in completely working order when cut up in 1985-6.
Of the second generation, there were only three classes eventually ordered: 35 being the first, then 47 and 50. Once again it was actually the type 3 which prove to be the most reliable and "designed for task, delivered to design" . Both the 50s and the 47s required extremely expensive refurbishment to overcome their reliability issues, and in effect the 47s in particular did not live up to their design missive.
Brush Traction then had a pragmatic approach to what was still fairly experimental machinery. They had already shown this in re-engining the problematic and underpowered type 2 AIAs, and took a sensible decision to de-rate the new type 4s after rectifiying the terrible problems with the Sulzer units. One of the key issues was most likely caused by sulzer sub contracting production of the LDA series engines out, and thus quality control at various levels was not fulfilled.
In life, however, the sulzer 12LDA twin bank engine prove easy to both rectify and "keep on top of" with regular, specific maintainance. It is a single turbo engine with otherwise good access to components and inspection points. This contrasted with its own cousin, the 12 and 16 LVAs which had "blind" spots in the crank cases which lead to catastrophic failure due to a simple locating pin tool being ill machined! The 12LDA units could be hammered back into service rapidly, and given the amount of idle service duffs seemed to get in some areas when the more powerful 56s and 8s came in or when pairs of class 37s or 31s were needed to start heavy loads the 47 couldn't cope with in its solo existence, then class availability was kept artificially high. A better measure is MPC: miles per casualty, and for the same high speed services as the 50s, the 47s faired no better in fact!
The 47's legacy really lived on because Brush won the lions share of the two next generations of locomotive orders in the class 56 and 60. The nickname "duff" has cast a long shadow in UK locomotive history.
In the mean time however, GEC had gone into Alsthom and had concentrated on mainly AC locos for mainland europe with only relatively small orders for the "prima" units, tha majority of those for France and the UK, with the rebuild of the 333s being just that. It was the USA who had kept advancing diesel loco technology in heavier RA7 + freight locomotives, and actually could offer units down to under 120 tonnes based around the GM 645 line of PUs and CoCo format.
The failure of the 56s to haul the heaviest trains in the UK, lead to the class 59 outshining all but the "tugs" when they came on the scene. Major teething problems once again with the 60s meant that in the soon-to-be private world the EMD class 66 would rule the rails. ( although as a footnote, the USA proiduced Class 70 has had its share of teething problems)
So in a way, the perpetual under-delivery by Brush and compacency by GEC Alsthom opened the gates for the very competent N.American GM-EMD to swing in. WIth the Class 60s likely to be withdrawn or rationalised, we will one day soon see the end of UK produced locomotives on British metals.
lørdag 5. mars 2011
The British Rail Class 38.......that never was
The class 38 was perhaps quite near to being a signed deal, but the new reduced cylinder type 4 or 5 freight loco was what actually transpired from the successful 37/9 trial.
But what would the class 38 have actually looked like? How would it perform? Would it be like the 60 - freight dedicated -or like it's type 3 cousins, a jack of all trades?
Historical Context
All of the type threes and the nearly type three class 31, had shown that their superior punch in a small package made them winners over the under powered type 2s. At this approximate power banding, 1.4kw, it was deemed potentially useful to continue with newer locomotives which would work medium freight services, track maintainance and perhaps passenger trains. Another main purpose of the 37/9 trial was to estabish if reduced number of cylinders could be effective in operation: ie the far higher power per cylinder offerings in fewer and in line cylinder arrangements would be as reliable as the somewhat over engineered V12 and V16s of the 1950s,60s and 70s which were to be replaced.
The obvious choice of test bed for the proposed class 38 was of course the class 37. The engine compartment and radiator surface-area could accomodate a wide range of power units (PU's) : all from the two straight sixes chosen, through the GM645 unit and even up to the v16s in valenta/ Vp 185 or perhaps an RK 270 v16 - remember the portugeuse C1800s where shorter and lighter than the cl. 50.
At the time though the principle cost concern was what diesel mechanics call "unit man hours", a unit being a single cylinder and thus a multiple of these being considered the key cost driver. Heavy maintainance on the RK16 was costly, and the newer RK 12 has often been quoted as "over powered" and relatively unreilable by drivers and enthusiasts.
The eventual move to fewer cylinder "units" prove not to be quite as smooth as the 37/9 trial, with the expensive mistakes made on the class 60 with the MB275T/ 8 PU. However, no matter the teething issues with the PU in the "tugs", man hours and replacement components are indeed the major cost in maintaining a PU. Thus both straight 6 PUs chosen fulfill this criteria and establish if higher pressure PUs could operate at least as reliably as the best examples of the class 37s at Cardiff Canton where the trial was initiated.
What Form for the Class 38 ?
The class 38 would of course have been a standard "slab end" loco and would have followed the conventions at the time in being either similar or even standard in some elemetns to the two other UK locos viz. 56/58 or the US built class 59 perhaps. Given the contract had been placed with Brush Traction Ltd, as per the class 60, then the appearance would have been no doubt standard to the front end of the 60s. In essence the class 60 body is just a reworking of the 47 and 56 stressed frame.
One variation could have been employing a "Bone" format akin to class 20 and 58: at the time of the 60 order, the bone format had been clearly shunned on BR with a preference for walk through bodies allowing all weather access for inspection. With the whole design strategy being based on in line PUs, then a good deal of inspection and repair could be achieved in situ within a full width body. Furthermore, this would allow for more space for inclusion of a (redesigned!) silencer unit.
To Co or not To CoCo....
The MB275 unit is despite being only 5 mm wider in cylinder bore, considerably heavier than the RK270-6Tt unit, and in fact heavier than the original 18 tonne 12CSVT fitted in the Class 37. Being two stroke, the engine has longer stroke than the RK 270 (mm) and in general is far sturdier built to accomodate higher compression. In addition the crank case is a larger volume with large inspection ports for each "big end/con rod" connection to the crank shaft.
Therefore if the MB275 had been chosen then the loco would almost certainly have been a CoCo.
Power Unit Deciding Ultimate Bogie Arrangement
BRB had been somewhat dissatisfied with the RK reliability and service costs and also the delivered performance in classes 56 and 58. The PUs required more servicing than desirable, and it was seen that less cylinder units could offer cheaper servicing. Dissatisfaction was also all too evident at some customers like Foster Yeoman who ordered the GM 645 based class 59s as a result of poor class 56 performance, the road to GM EMD being paved and the UK industry's fate being more or less sealed as 'also ran'. I actually saw a FS stone test train with double class 56s in 1985 at Bristol Temple Meads Station, a service which a single 59 could tackle. So the Ruston RK 6 (or eventually 8) engine was not perhaps the lead runner.
In the final reckoning of course,m the superior power rating of the the MB 275 stratight 8 over the RK 8 lead to the former being chosen for the type 5 project, the class 60. The RK 8 in traction set up would be at a maximum rating of about 2800hp in the late 1980s, probably being favoured at a lower 2500hp to extend service interval. Coupled to SEPEX or GEC-Alsthoms latest power delivery & wheel slip control at the time, then a 2500 rating would have outperformed all the 12LDA locos and probably the standard class 56s and 58s.
On the other hand, in defence of the Rustons offering, there were several classes existing at the time which had a longevity expected with their RK / C/ SVT power units: 08, 20, 31, 37, 50, 56 and 58. Many components were "backwards compatible" eg new pistons from 58s into 37s, engine blocks from withdrawn 56s in class 50 life extension and so on. The MB 275 was completely unproven in a traction environment at that time, and Mirrlees had not enjoyed a very enviable reputation for their other traction power units, being swapped out of at least two types of brush locomtives and not favoured in the HST/ IC125 contract despite being trialled.
The RK 6 is four stroke and therefore uses less lubrication oil and probably has a longer heavy-refurbishment programme than the 6 cyl, MB275. Class 37s had proven to be masters of the type 3 power range, over-shadowing performance of their heavy and sluggish big sisters the 40s and providing more reliable service than all other type 4s. So this also stood in favour of Ruston's offering.
Details of the 37/9 trial are not fully released to the public, but however several commentators at the time stated better delivery with the MB but better service interval on the RK. The RK unit was fitted with some complex turbo lag synchronisation control, delivering fuel slowly until the turbo pressure was achieved. Hence the name "slugs".
With the smaller and much lighter RK6 being chosen form of the locomotive, the class 38 layout could then be left a little bit more open: Co Co configuration with the compact RK270 6T would have necessitated ballasting for heavy freight allocation, or indeed in any intended guise over six axels, as it weighs several tonnes less than the 12 CSVT, being essentially a single bank of that v12 engine and more like a class 08 RK footprint! This ballasting could have been a usefulk feature, with variable axel loading facilitated by lifting out the ballast depending on route and train type allocations.
An alternative just for the sake of arguement, could have been an AIA configurations: this could free up the trailing axel for advanced hydraulic braking or a dedicated rheostatic brake "motor". There are some electrical advantages in having only four traction motors to feed at this ampage/ voltage range in traction power application: these are much speculated upon by class 31 enthusiasts in comparison to the more powerful 37s. Also given the advanced SEPEX traction motors being a likely part of the order, then this electro-mechanical advantage could have rendered CoCo uneconomic: ie utilising a maximum kilo newton starting and continuous effort for the total power out put and axel loading over two SEPEX thus negating using standard TMs or bothering to employ six such advanced TMs.
The obvious option for reduced cost though would have been to produce a BoBo locomotive: Less materials in a shorter locomotive. The RK 6 engine is only slightly larger and heavier than the 280mm bore 6LDA 28 engines engines fitted to so many type 2s on BR and further a field. Although I find no interwebie quote for the type 3 rated 8LDA unit from the class 33, It is probably slightly heavier than the RK 6.
The success of the class 33 could have pointed to a SEPEX based locomotive being a sensible BoBo "Little sister" to the class 60 project. In fact the entire class 38 project had already been achieved by Brush traction when they re-engined their own "mini grids" : a class of BoBo locomotives made for Rhodesia / Zimbabwe. These were fitted latterly with RK 8 cylinder engines with a rating IIRC of around 1800 to 2000 hp and a tonnage under 80 gross. These suprising cousins to the 56s did have some good web listings and images a few years ago, an excellent british export locomotive site being amongst them. However, due no doubt to both copyright issues on images used and sources, and the closed nature of Zimbabwe as far as the internet goes, details of these locos are beyond my patience to find. I would be grateful for any links to provide some providence in this case. I would be very grateful for any links placed in "comments" below, by means of providing providence for this class of loco!
Total wieght at under 78 tonnes would later be advantagous for track access charging. However, there are several stumbling blocks for this BoBo arrangement: firstly the type of duties expected of a type 3 would include the torturous routes negotiated by 37s:
One reason 37s were introduced to the WHL and FNL/Kyle routes was to both accelerate trains while reducing corner wear over the type 2 bobos. By 1986 though, articulated CP5 bogies had been deemed a success though so a BoBo could have been practical in a new build. So this is one factor to consider: route availability and effective wear and tear.
The RK 270 is a longer unit than the 6lda, thus taking up much of the space in a locomotive as in the class 33. This would mean that features like rheostatic heat dissapators or indeed an auxilliary ETH generator would be excluded. One final factor I come upon to negate the use of Bobo is that a modern CoCo is in effect an AAA configurations: each traction motor can be independently removed or supplied less power ( in fact any 37 TM could be bumped out of connection, so they were in fact not a series connected CoCo) Heat dissapation is also a major consideration in a 1.4kw plus PU system and 37s had proven that their high ampage and resulting power delivery at low speeds was ideal for the CoCo configuration. So given the demands of heavy frieght and gradient work as a replacment to the 37s and 40s etc, and supplement to type 4s and 5s, the 38s would have done well to benefit from wheel slip / traction control in CoCo set up.
Final comment on CoCo: if the loco was to be a true mixed traffic entitity then the fitting of a 400- 600 hp auxiallary would have rendered a 2000hp prime mover with SEPEX TMS in a modern loco more effective than any of the then current sulzer type 4s when hauling ETH stock. A CoCo would allow for both this and space to carry ballast, while most likely offering better wheel slip and power delivery management than a bobo at the time of potential ordering in the late 80s.
Conclusion on Format:
At the end of the day, given the class 38 order went ahead in the same time
frame as the actual class 60 order, , then the Mb engine would be the choice to offer standardisation between the type 5 and type 3 erm, 3.5. Hence the loco would really need to be a CoCo to carry the weight and no doubt tackle the thumping torque -amps delivery of the big two stroke PU. It may have even been desirable to use the exact same body shell to give even more standardisation.
Had the order been put out to tender a little later in hypothetical time, then one tendering partner would have been the GEC altsthom with their Prima format, which has by in large been manufactured in BoBo format in both electric locos and the GM 645 based builds including the class 67s. With the light RK in their portfolio, then the loco would almost certainly have been a bobo and perhaps run alongside the royal mail /BRB build of the rather horrid class 67s.
Had BR decided to be rid of the underpowered type 2 fleet at an earlier date when their obselecense was clear, say 1976, then they could have looked to rationalise over to 8lda and ETH for a great number of class 25s and then build a new BoBo with brush at the time of the 56 order, as per the Rhodesian mini-grids discussed above.
Workings for the Proposed Class 38
What would they have worked? Well of course they would have worked all those mid wieght, mid speed services and track maintainance duties which class 37s have only now been by-in-large withdrawn from. Thus the class 38 would have lead to an earlier demise of the majority of the class 37 and probably all other type 2 and 3s, if they lived up to their promise of longer service hours, lower MPC and faster HGR turn around.
The 38s would have offered the opportunity to replace the earlier sulzer 45/46s from freight duties and supplement 47 freights, perhaps offering a heavier over all standing lift. In pairs they would have outperformed all the single type 4s and 5s of the early 1980s ( a pair of 37s would out perform 56s and 58 in sinlge unit operations according to motherwell depot). In the rush to dieselise in a post war britain still having materials rationing, pairing locomotives was seen as wasteful. However it is common practice in most long haul countries, where by larger "robot" multiples are often only engaged for gradients or actually switched off when running the wagons on "light" return journeys. Given that a pair of 38s would put out "type 6" power with 12 cylinders and be able to run light journeys on one unit, there may well have been an ongoing appeal from managers at depots like motherwell, Eastfield, Immingham, gateshead and Cardiff Canton.
Passenger wise, the 38s would have seen some employment even if they were nominally a freight ony locomotive given the same developments in the private era as transpired. However any potential order would probably have kept an eye on WHL sleeper services, routes like bangor, scarborough, Hull, Aberystwyth, Welsh Border Route and the potential for electric units / forwarding services to be operated by a light and fuel efficient loco.
If the class had been ordered as a freight only, this would have been under the BR sector scheme and so there would have been some debate upon privitisation and the ubiquity of class 66s as to the class 38's utilitity.
Now we see that the class 15x series multiple units are seeing the end of their effective lives and indeed the later generation units are showing signs of deminishing reliability, the 38s could have picked up where the 37s left off, working long distance semi expresses and hauling both de-engined 156s etc and things like 318s on services to say Lincoln, Hull, Bangor, Abersysthwyhth and in Scotland.
Fleet Size and Order-Number ?
Given BRB were serious in replacing earlier loco types 2 and -3, then the order could have been in the region of 150 to 200 examples. The author considers that both a super low geared and a higher geared "stroke 4" passenger dedicated variant sub class could have been subsequent orders upon successful experiences in core frieghts.
However the type of sub 1000 tonne traffic was drying up and becoming uneconomic. Also passenger traffic was strategically set over to multiple units: there was hope on a larger degree of standardisation, economic viability and reliability, all of which have proven dubious and probably not of any benefit if you compared the second or third generation DMUs with running class 31,33 and 37 (with 35 in there for historical noeworthyness!)
In the privatisation period, then private owners would have been very happy to exclude everything from class 20 to class 37 and rather own a single type 3 for lighter workings where a class 66 burns a lot of diesel! However, they were otherwise delivered fleets of pretty reliable "legacy" locos at bargain basement prices: some speculate that the acquisition of locos was less than scrap value in the total equation. There was no impetus for a new type 3 post privatisation due to this and now with network rail being national they struggle on with legacy 37s etc while 66s and 60s are often seen on rather puny track maintainance or even weed killer trains, and class 67s have appeared on many services which were otherwise completely adequately delivered by class 37/4s. In 2008, a large number of class 60s were stored as were many 67s and even 92s. It was claimed that there was not the demand for these locomotives.
As of time or writing, with no credible incentive to reduce axel weights or introduce locomotives on semi-fast services poorly served by DMUs, then there is little sign of any possible replacement to the recently pensioned type 3s.
Conclusions
The worrying issue for us at the time of the 37/9 trial, was if class 37s would routinely become "slugs". However, the refurbishment and "reallocation" programme showed the 12 CSVT to be a venerable and over engineered item which would last at least another ten years as planned, and of course nearly three decades in profit making service in reality.
If the RK 6 was chosen, then the loco would have almost certainly taken a BoBo format, while the MB275 lump would necessitate six axels. Intriguingly, the RK 8 could also be fitted into an RA6 / 7 Bo Bo loco as brush had done some years earlier to their Zimbabwe-Rhodesian "mini grid" bobos. My speculation ends there.
From all accounts however, the straight sixes were always planned to go in a new loco or be a test bed for reduced "unit" cylinder practicality for the larger "8s", and the latter was the project goal which prove desirable and came to fruition.
But what would the class 38 have actually looked like? How would it perform? Would it be like the 60 - freight dedicated -or like it's type 3 cousins, a jack of all trades?
Historical Context
All of the type threes and the nearly type three class 31, had shown that their superior punch in a small package made them winners over the under powered type 2s. At this approximate power banding, 1.4kw, it was deemed potentially useful to continue with newer locomotives which would work medium freight services, track maintainance and perhaps passenger trains. Another main purpose of the 37/9 trial was to estabish if reduced number of cylinders could be effective in operation: ie the far higher power per cylinder offerings in fewer and in line cylinder arrangements would be as reliable as the somewhat over engineered V12 and V16s of the 1950s,60s and 70s which were to be replaced.
The obvious choice of test bed for the proposed class 38 was of course the class 37. The engine compartment and radiator surface-area could accomodate a wide range of power units (PU's) : all from the two straight sixes chosen, through the GM645 unit and even up to the v16s in valenta/ Vp 185 or perhaps an RK 270 v16 - remember the portugeuse C1800s where shorter and lighter than the cl. 50.
At the time though the principle cost concern was what diesel mechanics call "unit man hours", a unit being a single cylinder and thus a multiple of these being considered the key cost driver. Heavy maintainance on the RK16 was costly, and the newer RK 12 has often been quoted as "over powered" and relatively unreilable by drivers and enthusiasts.
The eventual move to fewer cylinder "units" prove not to be quite as smooth as the 37/9 trial, with the expensive mistakes made on the class 60 with the MB275T/ 8 PU. However, no matter the teething issues with the PU in the "tugs", man hours and replacement components are indeed the major cost in maintaining a PU. Thus both straight 6 PUs chosen fulfill this criteria and establish if higher pressure PUs could operate at least as reliably as the best examples of the class 37s at Cardiff Canton where the trial was initiated.
What Form for the Class 38 ?
The class 38 would of course have been a standard "slab end" loco and would have followed the conventions at the time in being either similar or even standard in some elemetns to the two other UK locos viz. 56/58 or the US built class 59 perhaps. Given the contract had been placed with Brush Traction Ltd, as per the class 60, then the appearance would have been no doubt standard to the front end of the 60s. In essence the class 60 body is just a reworking of the 47 and 56 stressed frame.
One variation could have been employing a "Bone" format akin to class 20 and 58: at the time of the 60 order, the bone format had been clearly shunned on BR with a preference for walk through bodies allowing all weather access for inspection. With the whole design strategy being based on in line PUs, then a good deal of inspection and repair could be achieved in situ within a full width body. Furthermore, this would allow for more space for inclusion of a (redesigned!) silencer unit.
To Co or not To CoCo....
The MB275 unit is despite being only 5 mm wider in cylinder bore, considerably heavier than the RK270-6Tt unit, and in fact heavier than the original 18 tonne 12CSVT fitted in the Class 37. Being two stroke, the engine has longer stroke than the RK 270 (mm) and in general is far sturdier built to accomodate higher compression. In addition the crank case is a larger volume with large inspection ports for each "big end/con rod" connection to the crank shaft.
Therefore if the MB275 had been chosen then the loco would almost certainly have been a CoCo.
Power Unit Deciding Ultimate Bogie Arrangement
BRB had been somewhat dissatisfied with the RK reliability and service costs and also the delivered performance in classes 56 and 58. The PUs required more servicing than desirable, and it was seen that less cylinder units could offer cheaper servicing. Dissatisfaction was also all too evident at some customers like Foster Yeoman who ordered the GM 645 based class 59s as a result of poor class 56 performance, the road to GM EMD being paved and the UK industry's fate being more or less sealed as 'also ran'. I actually saw a FS stone test train with double class 56s in 1985 at Bristol Temple Meads Station, a service which a single 59 could tackle. So the Ruston RK 6 (or eventually 8) engine was not perhaps the lead runner.
In the final reckoning of course,m the superior power rating of the the MB 275 stratight 8 over the RK 8 lead to the former being chosen for the type 5 project, the class 60. The RK 8 in traction set up would be at a maximum rating of about 2800hp in the late 1980s, probably being favoured at a lower 2500hp to extend service interval. Coupled to SEPEX or GEC-Alsthoms latest power delivery & wheel slip control at the time, then a 2500 rating would have outperformed all the 12LDA locos and probably the standard class 56s and 58s.
On the other hand, in defence of the Rustons offering, there were several classes existing at the time which had a longevity expected with their RK / C/ SVT power units: 08, 20, 31, 37, 50, 56 and 58. Many components were "backwards compatible" eg new pistons from 58s into 37s, engine blocks from withdrawn 56s in class 50 life extension and so on. The MB 275 was completely unproven in a traction environment at that time, and Mirrlees had not enjoyed a very enviable reputation for their other traction power units, being swapped out of at least two types of brush locomtives and not favoured in the HST/ IC125 contract despite being trialled.
The RK 6 is four stroke and therefore uses less lubrication oil and probably has a longer heavy-refurbishment programme than the 6 cyl, MB275. Class 37s had proven to be masters of the type 3 power range, over-shadowing performance of their heavy and sluggish big sisters the 40s and providing more reliable service than all other type 4s. So this also stood in favour of Ruston's offering.
Details of the 37/9 trial are not fully released to the public, but however several commentators at the time stated better delivery with the MB but better service interval on the RK. The RK unit was fitted with some complex turbo lag synchronisation control, delivering fuel slowly until the turbo pressure was achieved. Hence the name "slugs".
With the smaller and much lighter RK6 being chosen form of the locomotive, the class 38 layout could then be left a little bit more open: Co Co configuration with the compact RK270 6T would have necessitated ballasting for heavy freight allocation, or indeed in any intended guise over six axels, as it weighs several tonnes less than the 12 CSVT, being essentially a single bank of that v12 engine and more like a class 08 RK footprint! This ballasting could have been a usefulk feature, with variable axel loading facilitated by lifting out the ballast depending on route and train type allocations.
An alternative just for the sake of arguement, could have been an AIA configurations: this could free up the trailing axel for advanced hydraulic braking or a dedicated rheostatic brake "motor". There are some electrical advantages in having only four traction motors to feed at this ampage/ voltage range in traction power application: these are much speculated upon by class 31 enthusiasts in comparison to the more powerful 37s. Also given the advanced SEPEX traction motors being a likely part of the order, then this electro-mechanical advantage could have rendered CoCo uneconomic: ie utilising a maximum kilo newton starting and continuous effort for the total power out put and axel loading over two SEPEX thus negating using standard TMs or bothering to employ six such advanced TMs.
The obvious option for reduced cost though would have been to produce a BoBo locomotive: Less materials in a shorter locomotive. The RK 6 engine is only slightly larger and heavier than the 280mm bore 6LDA 28 engines engines fitted to so many type 2s on BR and further a field. Although I find no interwebie quote for the type 3 rated 8LDA unit from the class 33, It is probably slightly heavier than the RK 6.
The success of the class 33 could have pointed to a SEPEX based locomotive being a sensible BoBo "Little sister" to the class 60 project. In fact the entire class 38 project had already been achieved by Brush traction when they re-engined their own "mini grids" : a class of BoBo locomotives made for Rhodesia / Zimbabwe. These were fitted latterly with RK 8 cylinder engines with a rating IIRC of around 1800 to 2000 hp and a tonnage under 80 gross. These suprising cousins to the 56s did have some good web listings and images a few years ago, an excellent british export locomotive site being amongst them. However, due no doubt to both copyright issues on images used and sources, and the closed nature of Zimbabwe as far as the internet goes, details of these locos are beyond my patience to find. I would be grateful for any links to provide some providence in this case. I would be very grateful for any links placed in "comments" below, by means of providing providence for this class of loco!
Total wieght at under 78 tonnes would later be advantagous for track access charging. However, there are several stumbling blocks for this BoBo arrangement: firstly the type of duties expected of a type 3 would include the torturous routes negotiated by 37s:
One reason 37s were introduced to the WHL and FNL/Kyle routes was to both accelerate trains while reducing corner wear over the type 2 bobos. By 1986 though, articulated CP5 bogies had been deemed a success though so a BoBo could have been practical in a new build. So this is one factor to consider: route availability and effective wear and tear.
The RK 270 is a longer unit than the 6lda, thus taking up much of the space in a locomotive as in the class 33. This would mean that features like rheostatic heat dissapators or indeed an auxilliary ETH generator would be excluded. One final factor I come upon to negate the use of Bobo is that a modern CoCo is in effect an AAA configurations: each traction motor can be independently removed or supplied less power ( in fact any 37 TM could be bumped out of connection, so they were in fact not a series connected CoCo) Heat dissapation is also a major consideration in a 1.4kw plus PU system and 37s had proven that their high ampage and resulting power delivery at low speeds was ideal for the CoCo configuration. So given the demands of heavy frieght and gradient work as a replacment to the 37s and 40s etc, and supplement to type 4s and 5s, the 38s would have done well to benefit from wheel slip / traction control in CoCo set up.
Final comment on CoCo: if the loco was to be a true mixed traffic entitity then the fitting of a 400- 600 hp auxiallary would have rendered a 2000hp prime mover with SEPEX TMS in a modern loco more effective than any of the then current sulzer type 4s when hauling ETH stock. A CoCo would allow for both this and space to carry ballast, while most likely offering better wheel slip and power delivery management than a bobo at the time of potential ordering in the late 80s.
Conclusion on Format:
At the end of the day, given the class 38 order went ahead in the same time
frame as the actual class 60 order, , then the Mb engine would be the choice to offer standardisation between the type 5 and type 3 erm, 3.5. Hence the loco would really need to be a CoCo to carry the weight and no doubt tackle the thumping torque -amps delivery of the big two stroke PU. It may have even been desirable to use the exact same body shell to give even more standardisation.
Had the order been put out to tender a little later in hypothetical time, then one tendering partner would have been the GEC altsthom with their Prima format, which has by in large been manufactured in BoBo format in both electric locos and the GM 645 based builds including the class 67s. With the light RK in their portfolio, then the loco would almost certainly have been a bobo and perhaps run alongside the royal mail /BRB build of the rather horrid class 67s.
Had BR decided to be rid of the underpowered type 2 fleet at an earlier date when their obselecense was clear, say 1976, then they could have looked to rationalise over to 8lda and ETH for a great number of class 25s and then build a new BoBo with brush at the time of the 56 order, as per the Rhodesian mini-grids discussed above.
Workings for the Proposed Class 38
What would they have worked? Well of course they would have worked all those mid wieght, mid speed services and track maintainance duties which class 37s have only now been by-in-large withdrawn from. Thus the class 38 would have lead to an earlier demise of the majority of the class 37 and probably all other type 2 and 3s, if they lived up to their promise of longer service hours, lower MPC and faster HGR turn around.
The 38s would have offered the opportunity to replace the earlier sulzer 45/46s from freight duties and supplement 47 freights, perhaps offering a heavier over all standing lift. In pairs they would have outperformed all the single type 4s and 5s of the early 1980s ( a pair of 37s would out perform 56s and 58 in sinlge unit operations according to motherwell depot). In the rush to dieselise in a post war britain still having materials rationing, pairing locomotives was seen as wasteful. However it is common practice in most long haul countries, where by larger "robot" multiples are often only engaged for gradients or actually switched off when running the wagons on "light" return journeys. Given that a pair of 38s would put out "type 6" power with 12 cylinders and be able to run light journeys on one unit, there may well have been an ongoing appeal from managers at depots like motherwell, Eastfield, Immingham, gateshead and Cardiff Canton.
Passenger wise, the 38s would have seen some employment even if they were nominally a freight ony locomotive given the same developments in the private era as transpired. However any potential order would probably have kept an eye on WHL sleeper services, routes like bangor, scarborough, Hull, Aberystwyth, Welsh Border Route and the potential for electric units / forwarding services to be operated by a light and fuel efficient loco.
If the class had been ordered as a freight only, this would have been under the BR sector scheme and so there would have been some debate upon privitisation and the ubiquity of class 66s as to the class 38's utilitity.
Now we see that the class 15x series multiple units are seeing the end of their effective lives and indeed the later generation units are showing signs of deminishing reliability, the 38s could have picked up where the 37s left off, working long distance semi expresses and hauling both de-engined 156s etc and things like 318s on services to say Lincoln, Hull, Bangor, Abersysthwyhth and in Scotland.
Fleet Size and Order-Number ?
Given BRB were serious in replacing earlier loco types 2 and -3, then the order could have been in the region of 150 to 200 examples. The author considers that both a super low geared and a higher geared "stroke 4" passenger dedicated variant sub class could have been subsequent orders upon successful experiences in core frieghts.
However the type of sub 1000 tonne traffic was drying up and becoming uneconomic. Also passenger traffic was strategically set over to multiple units: there was hope on a larger degree of standardisation, economic viability and reliability, all of which have proven dubious and probably not of any benefit if you compared the second or third generation DMUs with running class 31,33 and 37 (with 35 in there for historical noeworthyness!)
In the privatisation period, then private owners would have been very happy to exclude everything from class 20 to class 37 and rather own a single type 3 for lighter workings where a class 66 burns a lot of diesel! However, they were otherwise delivered fleets of pretty reliable "legacy" locos at bargain basement prices: some speculate that the acquisition of locos was less than scrap value in the total equation. There was no impetus for a new type 3 post privatisation due to this and now with network rail being national they struggle on with legacy 37s etc while 66s and 60s are often seen on rather puny track maintainance or even weed killer trains, and class 67s have appeared on many services which were otherwise completely adequately delivered by class 37/4s. In 2008, a large number of class 60s were stored as were many 67s and even 92s. It was claimed that there was not the demand for these locomotives.
As of time or writing, with no credible incentive to reduce axel weights or introduce locomotives on semi-fast services poorly served by DMUs, then there is little sign of any possible replacement to the recently pensioned type 3s.
Conclusions
The worrying issue for us at the time of the 37/9 trial, was if class 37s would routinely become "slugs". However, the refurbishment and "reallocation" programme showed the 12 CSVT to be a venerable and over engineered item which would last at least another ten years as planned, and of course nearly three decades in profit making service in reality.
If the RK 6 was chosen, then the loco would have almost certainly taken a BoBo format, while the MB275 lump would necessitate six axels. Intriguingly, the RK 8 could also be fitted into an RA6 / 7 Bo Bo loco as brush had done some years earlier to their Zimbabwe-Rhodesian "mini grid" bobos. My speculation ends there.
From all accounts however, the straight sixes were always planned to go in a new loco or be a test bed for reduced "unit" cylinder practicality for the larger "8s", and the latter was the project goal which prove desirable and came to fruition.
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