GWR Autocoach operation.

[PMP99]

Apologies if this has been covered elsewhere, but I couldn’t immediately find anything.

 

All the pictures I have seen of single coach / 14xx operation show the loco running chimney first when the loco is leading. Did they ever run bunker first when the loco was leading?
 

(Obviously they ran bunker leading at times when in the middle of a multiple coach formation)

 

Any advice appreciated.

 

Graham

[Miss Prism]

I can't find any bunker-leading yet.

[Hal Nail]

 

[PMP99]

6 minutes ago, Hal Nail said:

 

Thanks, that looks an interesting thread. I hadn’t considered searching for ‘push/pull’ working (or pull-push) in this case.

 

Graham

[Piemanlarger]

I saw a video of a 48xx  bunker first the other day.

I'll see if I can find the details as it did catch my eye as being unusual. 

[petrox]

"Railways in and around Newton Abbott & Torquay" by C.R. Potts - page 62, 14xx & autocoach leaving Churston bunker first. I guess it is possible that it was not being worked in auto mode?

Pete

[Rivercider]

It does seem to be usual for a 14XX to be coupled with the chimney leading, I have quite a lot of photos in my book collection.

I have found two examples of a 14XX coupled the other way round, while definitely propelling the auto coach.

 

The Brixham Branch by C R Potts, (Oakwood Press) after page 80, 1466 is approaching Churston propelling the autocoach, and hauling a fish truck.

 

The Exe Valley Railway by John Owen page 26, 1450 is propelling the trailer towards Tiverton Junction.

Perhaps significantly the author says it  'was extremely rare on 'up' trains, the locomotive invariably hauling its coach out to the Junction and propelling it back'.

Perhaps something had happened to the booked auto set and this pair had been hastily used as a replacement?   

 

I also wonder if the bunker leading formation being less photogenic was sometimes ignored by photographers, so was perhaps actually more common than photographic records show?

 

cheers  

[chrisf]

Re the photo of 1466 at Churston:  I think 1466 was "the wrong way round" because it faced that way for regular work on one of the other local branches, either Ashburton or Moretonhampstead.

 

There is no reason for a bunker first auto fitted loco to work in non-auto mode when coupled to a trailer, though it did happen on at least one railtour.  Back in the day there were instances of auto trains whose day's work would leave them facing in the opposite direction.  One that comes to mind is the Barry working which was booked to traverse three sides of a triangle.

 

Chris  

[PMP99]

1 hour ago, Rivercider said:

 

 

I also wonder if the bunker leading formation being less photogenic was sometimes ignored by photographers, so was perhaps actually more common than photographic records show?

 

cheers  

Yes, that crossed my mind too. May well be a combination of that and a rarer operating practice.

[Compound2632]

Could the Great Western's mechanical control work with the engine facing the driving trailer? How was sandwich operation achieved? Did the control system had to be re-rigged on reversal so the train could be driven from the driving trailer at the other end?

 

In the Midland/LMS vacuum control system, the engine could be either way round.

[chrisf]

If I understand correctly, sandwich operation works because the trailers are opposite ways round and the gear on the loco is configured such that it will work whether the loco be chimney or bunker first.  If I've got this right, if the loco abuts the cab end of the trailer the rodding will not couple.  The mechanics of all this must have vexed some people on the GWR/WR to judge by the detailed instructions covering auto operation on the Staines West and Uxbridge branches published in the small print of the carriage working programme.

 

Chris

[Siberian Snooper]

In the Plymouth area where sandwich operation was prevalent the sidings were arranged such that a loco could pick up trailers on either end of the loco.

 

If you look at the attached map, to the west of Laira Junction and above the mainline you can see the auto trailer sidings.

 

https://maps.nls.uk/view/106006919

 

 

 

[Blandford1969]

3 hours ago, chrisf said:

If I understand correctly, sandwich operation works because the trailers are opposite ways round and the gear on the loco is configured such that it will work whether the loco be chimney or bunker first.  If I've got this right, if the loco abuts the cab end of the trailer the rodding will not couple.  The mechanics of all this must have vexed some people on the GWR/WR to judge by the detailed instructions covering auto operation on the Staines West and Uxbridge branches published in the small print of the carriage working programme.

 

Chris

In fairness it does not matter which way round the coach is onto the connection. In sandwich mode both the mechanical links are left connected. the thing that is changed  is the rod connecting to the regulator. There are 2 which come up into the cab, one from each end. You just simply disconnect one and attach the other. They are of course awkward, or at least that on 1450 always seems to be. 

[JimC]

I wonder if it's significant that the trailers could only be driven from one end. That must have forced certain limitations on what could be done. 

 

Do we have anyone here who has driven a 14 or a 64? Could they comment on whether cab first or boiler first is more congenial? 

Edited January 23, 2021 by JimC

[Michael Hodgson]

If you're the driver of an auto train, you spend half your shift in the coach being propelled and you really don't care which way the fireman on the loco is facing.  You spend the other half of the shift on the loco, and probably find it more amenable to drive chimney first.  So when it comes to coupling up, why would you do it bunker first unless that's impractical because there's no turntable handy ?

[Darwinian]

Harold Gasson in one of his books recounts breaking the whistle chain between loco and trailer which swung down hitting the coach/cab. Could the whistle connection be made at the smokebox end or did the driver have to rely on the autocoach bell alone when being propelled? 

In general as mentioned above the loco could be turned to suit the working but if a replacement autocoach was needed maybe it was not always possible to turn it immediately.

[Blandford1969]

55 minutes ago, Darwinian said:

Harold Gasson in one of his books recounts breaking the whistle chain between loco and trailer which swung down hitting the coach/cab. Could the whistle connection be made at the smokebox end or did the driver have to rely on the autocoach bell alone when being propelled? 

In general as mentioned above the loco could be turned to suit the working but if a replacement autocoach was needed maybe it was not always possible to turn it immediately.

The whistle chain could be connected at either end. The one thing to note is the bell is not that loud, or at least it does not seem so when driving from the trailer having had the whistle chain break! . Personally I when in the loco cab I prefer driving smokebox first. Those windows are the biggest of any engine I've ever driven and give a marvellous view.  

[The Johnster]

The reason that auto traiilers only had a driving cab at one end is that they were originally designed to be used in conjunction with steam railmotors, which had cabs at both ends, coupled so that a driving cab was at each end of an SRM/Trailer set, and later, when the SRMs were converted to auto trailers, these used the 'trailing' end cab and the loco section, with it's cab, was replaced by seating and/or van accommodation.  A trailer could be coupled to either end of an SRM but the cab had to be 'outwards'.  In the Plymouth area, 4 car sets of SRM/Trailer sets ran, a prediction of later 'sandwich' operation.  One must bear in mind the rather piecemeal development of these trains; they were originally a response to compettiion for suburban work from the then new electric tramways, and were an urban 'thing' rather than the rural bucolism we tend to associate them with. Indeed, urban commuter auto traffic partly or entirely running on main lines was a feature of auto work until it's end.

 

The GW was by no means alone in contending for traffic with electric trams in this way, and the initial response was Steam Railmotors.  Almost everywhere, these were victims of their own success and trailers had to be provided to cope with the traffic.  Of course, these trailers needed a means of being driven from the other end of the train to the SRM cab, or one would have had to run around, defeating the quick turnaround capability of the trains that was part of the plan in the first place.  The simplest way to do this was with rods and joints linking the loco's regulator handle to one in the other cab, an extension of the original single SRM method; when the driver moved the regulator in the cab at the other end of the train, the regulator handle on the loco moved in concert, as if handled by a ghost...  The upshot, predicatble with 20/20 hind vision, was that the SRMs struggled with the trailing loads and better speeds were needed than their small driving wheels could provide.

 

The next step, assisted on the GW by taking place over a period during which a large number of redacted Victorian tank locos were becoming available, was to increase the number of trailers and use a loco.  You could now manage the loads (well, most of the time anyway), had greater speed available, needed to stop for water less often, and the loco could be (though usually wasn't) used for other work when the auto work was finished for the day, or before it started.  In addiction to new trailers and the incoporation of rural branches into the fold of auto working, the SRMs were converted to trailers, but as and when rather than as a program, so the process took several years over 3 decades.

 

There were exeptions of course, but the SRMs and the trailers were built in two lengths, 59'6" and 70', and were of two distinct types, 'suburban' and 'branch', the main difference being the provision of a guard's compartment on 'branch' trailers.  Initially, passengers entered and detrained through the driver's and guard's doors, the latter being the cab the driver wasn't using in the case of the 'suburban' trailers.  By the late 20s, new trailer design had settled to the well known pattern of 2 saloons separated by a wide vestibule which could be accessed by retractable steps, a development of the 'branch' trailer, and were no more than 59'6" in length, with the exception of the final saloon design, the A38/9, which used a Hawksworth underframe and was a 64footer.

 

The linkage system was not ideal and might have been done differently if the GW was starting from scratch in the 20s; there were other railways' systems that were based on air, vacuum, or steam operation, as well as types relying on overhead cables (TVR).  But in the event the system was already established and it was easy to convert trailers from absorbed railways at the grouping.  As has been said, the linkage was 'handed' so the trailer could only be coupled to the loco so that the driving cab faced away from the loco (bunker or smokebox end made no difference) if the auto gear was to be used.  The amount of play in the linkage joints meant that only two trailers could be coupled to the locos with the auto gear in use; any more and the regulator movement in the trailer cab could not be replicated aboard the loco.  The second trailer away from the loco was coupled to the first in the same way that the first was coupled to the loco.

 

So, auto train formations could be; loco/trailer, loco/trailer/trailer. trailer/loco/trailer, trailer/loco/trailer/trailer, trailer/trailer/loco/trailer, or trailer/trailer/loco/trailer/trailer.  Thee was no reason that normally hauled traffic could not be coupled in rear, subject to the loco's haulage capacity, or that trailers being hauled by auto fitted locos had to have the auto gear connected, but it was essential for propelling.  Auto trailers could also be hauled as normal coaches by locos not fitted with auto gear, but not propelled, even with a driver in the leading cab.

 

The trailer cabs were somewhat minimalist, having a regulator handle, vacuum brake setter and gauge, handbrake standard, and a treadle operated gong, as with two 70' trailers the whistle is 150 odd feet behind the front of the train and speeds up to 70 or so....  There was also a battery electric buzzer communication between driver, guard, and fireman.  With one exception no windscreen wiper was provided, but following a collision at Snow Hill gravity fed sand boxes were fitted to assist braking.

 

As they were alone unsupervised on the footplate for at least half and sometimes nearly all of a duty, passed firemen were preferred for auto duty, as in addition to his normal work managing the boiler and the fire, he would be prevailed upon to operatw the reverser, blower, and anything else the loco required of him. 

 

There were some trailers gangwayed within sets, notably in the Plymouth Area, whcih included driving trailers split by the gangway in the 'intermediate' inner trailers; the driving cabs must have been very rarely if ever used.  There were TVR sets gangwayed within the sets as well, numbered in the main coaching stock series, but in this case no driving compartment was provided for the intermediate trailer (AFAIK, anyway).  There were also compartment trailers, converted from brake 3rds and with intermediate trailers without driving cabs converted from matching all 3rds.  Both clerestory and non-clerestory Dean coaches were rebuilt in this way, the 'Cliton Downs' trailers being well known. 

 

In the 1930s, some Collett flat ended brake composites were similarly converted to auto for use on the Lydney-Sharpness 'Severn Bridge' service, which was jointly run with the LMS who stipulated that first class accommodation was available.  The cab ends had a single rectangular window and were the first of what were universally but not officiall called the 'Cyclops' type.  There were no intermediate non-driving matching coaches in this case.

 

The 'Cyclops' pattern was repeated, this time with Collett brake 3rds, also flat enders, for use in South Wales, where a timetable alteration in 1953 extended auto services in the Newport and Cardiff Valleys divisions, and these had matching non driving all third intermediate trailers to make 2 car sets.  There were more driving trailers than intermediates.  All of these compartment trailers were painted coach colour at the cab end and plain black at the other end, and (again, only TTBOMK) only the South Wales brake 3rd drving trailers were renumbed into the auto number series.  The two diagrams of 'Cyclops' flat end driving trailers were the only auto coaches fitted with windscreen wipers, presumably manually operated but I'm happy to be corrected on that point!

 

As the auto gear was standard across the fleet, any trailer could work with any auto fitted loco or any other trailer so long as they were facing the right way, but the gangwayed sets tended to stay in their pairs.  Once coupled up, the crews liked to leave the gear alone during the duty, and shunting was often carried out with the trailer attached at small stations where officialdom wotted not of what they were wont to wot.  This was allowed in some places by the relevant Sectional Appendix instructions. 

 

On the Lambourne branch, a featuer of the traffic was tail traffic of horseboxes, and in conjuntion with the longer distance and a number of ground level halt platforms needing the retractable steps, auto trailers were hauled by Dean Goods or 2251 tender locos as normal coaches.  Auto fitted locos could haul stock in the 'normal' sense of course, but were in demand for auto work and it was more common to see a 'normal' loco hauling auto trailers than an auto fitted locos hauling normal stock; this is not to say it never happened.  Of course, when a normal loco was hauling auto trailers as normal stock, it didn't matter which way round the trailers were. 

 

Locos were originally fully depreciated small tanks, available at no cost, 2021s, Metros, 517s being typical, both saddle and pannier 0-6-0s with inside and outside frames being used.  The first purpose built new auto loco was the Collett 48xx, later 14xx, a development of the 517 class, though there were still auto fitted 517s and Metros in very early BR days (doubt any carried BR livery)  1471, a 517, for many years the Woodstock branch loco, was unofficially named 'Fair Rosamund' (Henry II's mistress, and a local girl said to be the 'fairest in all England), a set of nameplates being carried.  The next development was a response to a need for more power for London area suburban work, a 2021 developed with 5'2" driving wheels as the 54xx class.  An adaptation of this with 4'7" driving wheels, the 64xx, was developed for the heavier loads and steeper gradients of South Wales and the Plymouth Area.  Finally, in 1953, a number of Churchward 4575 class small prairies were fitted with auto gear for service in South Wales in connection with the new timetable mentioned earlier, along with the A43/A44 compartment Cyclops and intermediate non driving trailers.  Non auto versions of the 48xx and 64xx, the 58xx  and 74xx respectively, followed the introduction of their parent classes.

 

I think that covers most of it, Graham.  I'd recommend John Lewis's books if you can find them anywhere (out of print and overpriced of course).  If I can help any more, just ask!

 

 

 

[Hal Nail]

Feels churlish to try and add to that comprehensive reply other than to point out that it was probably rare to find an auto trailer in a siding with only the cab end accessible, as would have taken a deliberate shunt to get it there?!

 

In terms of how they generally contrived to find a trailer facing the right way for a bunker connection (reminding me a bit of the similar brake van orientation thread), it wasn't just a case of turning the loco as many branches always had the loco the same way round. I'm curious to know were all coaches pooled for all lines (in the area) or would there be a branch regular? 

 

I've read that the first and last Fowey train (or loco movement) of the day ran over the freight only line from St Blazey. That would imply the coach either stayed attached to the loco, or was left at Fowey overnight, and whichever was the case, it must have required a separate trip to somewhere to swap the coach. Nevertheless I've seen at least 5 different trailer types attached just to 1419, let alone different examples of those.

Edited January 24, 2021 by Hal Nail

[Gordon A]

On 23/01/2021 at 06:25, chrisf said:

If I understand correctly, sandwich operation works because the trailers are opposite ways round and the gear on the loco is configured such that it will work whether the loco be chimney or bunker first.  If I've got this right, if the loco abuts the cab end of the trailer the rodding will not couple.  The mechanics of all this must have vexed some people on the GWR/WR to judge by the detailed instructions covering auto operation on the Staines West and Uxbridge branches published in the small print of the carriage working programme.

 

Chris

 

I think I have seen pictures of four auto coaches, two either side of the engine in the Plymouth area, so there did exist an auto working coupling on the cab end of the coach. 

[Poor Old Bruce]

On 22/01/2021 at 23:13, Compound2632 said:

In the Midland/LMS vacuum control system, the engine could be either way round.

 

The Buxton to Millers Dale PP trains usually ran with the chimney end coupled to the coach(es).

[David Bigcheeseplant]

Locos had a the same connection on both ends, which was a a short square mounting. On a autocoach there was a longer articulated square rod that folded up to the luggage end while not in use but connected to the loco. The driving end of the autocoach had the same connection as that on the loco.

 

steam railmotor could not be connected to autocoach at the engine end only the trailing end.

[Compound2632]

Given the simplicity of the Midland/LMS vacuum-controlled regulator system, I'm mystified as to why the Great Western persisted with its mechanical system.

[rab]

Just now, Compound2632 said:

Given the simplicity of the Midland/LMS vacuum-controlled regulator system, I'm mystified as to why the Great Western persisted with its mechanical system.

Probably because the GW always thought their way was best

[Poor Old Bruce]

If it ain't broke, don't fix it!