Tail-loads on DMU/railbus services- shunting? Brake vans?

[russ p]

5 hours ago, Wickham Green too said:

It does, indeed, imply that as it makes no differentiation .... BUT it does specifically say "WHEN COUPLING TOGETHER TWO INTER-CITY DIESEL VEHICLES ..... The gangway covers must be off and the buffers in the "short" position." - which doesn't make a lot of sense on vehicle ends with no gangways from which to remove covers. 

 

That was probably referring to 123 and 126/ Edinburgh Glasgow stock inner driving vehicles 

[Wickham Green too]

But, as I say, there is no specific reference to coupling two Leading Ends* -other than the the drawings on page 84. These clearly show the absence of a gangway compared with page 85 Intermediate End drawings but there is nothing to explain any difference in operation ( nor does it say there is no difference - which it's probably trying to imply ).

 

*or a Leading End with something else

[The Stationmaster]

18 hours ago, Wickham Green too said:

It does, indeed, imply that as it makes no differentiation .... BUT it does specifically say "WHEN COUPLING TOGETHER TWO INTER-CITY DIESEL VEHICLES ..... The gangway covers must be off and the buffers in the "short" position." - which doesn't make a lot of sense on vehicle ends with no gangways from which to remove covers. 

No need to remove gangway covers if there aren't any gangways, do need to remove them when coupling gangway to gangway - simple as that.    Any railwayman involved would understand that so theInstruction makes perfect sense to me.   Don't forget these Instructions were written for folk who should have known what they were at and the reference to gangway covers is important because of the wide range of situations in which they were, or weren't, required to be in place - thus it also brings this Instruction into line with more general Instructions.

 

Everybody would realise that you couldn't remove then if there were no gangways there in the first place so they don't need to be told that.  And equally don't forget that some driving ends on the InterCity unitsdid have gangways and could be coupled gangway to gangway.

[Wickham Green too]

Sorry, I have to disagree ........... it was thought necessary to provide different drawings for  Leading and Intermediate ends so I - that is me personally, as an engineer - would expect one or two words to complement those drawings.

[The Stationmaster]

4 hours ago, Wickham Green too said:

Sorry, I have to disagree ........... it was thought necessary to provide different drawings for  Leading and Intermediate ends so I - that is me personally, as an engineer - would expect one or two words to complement those drawings.

Hardly necessary.  the purpose of te cdrawings - where teh relevant items are identified - is simply to show where things are.  the purpose of the Instructions is to tell people what to do in various situations. No need for such words as 'use the item labelled 10 to extend the buffers' - they know that, what they need to know is under what circumstances the buffers must be extended.

 

So when you are writing an instruction you start with teh enginerring description of the parts, and illustrations, and you turn taht - which is basicalluy not much use to an operator - into Instructions which tel; an operator what he needs to knw and whe to do or not to  it.

 

Example when teh Bedford - Bletchley line was resignalled earlier this century the signalling contractor produced a document with keyed illustrations describing how to operate the barriers in emergency situation such as various sorts of failure.  I then had the job - because Railtrack didn't have anyone with the right sort of knowledge availble - of writing the Instructions for the operator who would operate the barriers in local control etc.   The resultant Instruction had to be compliant with normal Rules & Regs, referenced to them in the relevant places, and written using their terminology.  I obviously used the manufacturer's keyed illustrations for 'naming of the parts' but that was all they were useful for because any use of themby name had to be written into the relevant stage of th  Instructions (and translated from American to normal railway terminology.   Just the same here - the illustrations are good for 'naming of the parts' but that's about it because the rest has to be written from the roots and format set by other e relevant Rule Book and General Appendix items

[keefer]

IIRC on the Swindon Inter-City units (later used for Edinburgh-Glasgow), the 'leading' i.e. full-cab end cars did not have control jumpers/sockets, so would not normally be coupled to anything else in service.

However the other vehicles of sets were arranged, the full-cab car would have to be on the end.

The 126s had end control jumpers on the DMBS so were not affected in the same way.

Re: 'Lightweight' DMUs, I do recall reading somewhere that the were restrictions on tail-loads and also, if for some reason they were dead in a hauled train, the LW cars had to be at the back so as not not overload their drawgear.

 

Edited April 3, 2023 by keefer
Spelling

[Aire Head]

On 31/03/2023 at 22:54, roythebus1 said:

A "swinger" was also a vehicle with automatic brake that had the automatic brake inoperative. Not to be found on the rear-end of a train unless it has a hand brake!

 

Surely the Metropolitan Railway used the Undergound "standard" Ward coupler? Not miniature buckeyes.

Interestingly I've seen in the 1940 dated supplement to the 1937 LMS General Appendix that a single Unfitted vehicle is allowed to be attached as the rear vehicle to a "local passenger" train provided a screw coupling is used.

 

I can only image the swinging effect on a typical 9ft wheelbase vehicle of the period!

[Michael Hodgson]

44 minutes ago, Aire Head said:

Interestingly I've seen in the 1940 dated supplement to the 1937 LMS General Appendix that a single Unfitted vehicle is allowed to be attached as the rear vehicle to a "local passenger" train provided a screw coupling is used.

 

That was practice on some LMS branches, but I thought only where the gradients were limited. and then only on certain services nominated in the WTT (middle of the day rather than the peak commuter runs) and restricted to urgent traffic that couldn't wait till tomorrow's pick-up goods.  But the exigencies of WW2 might well have justified temporary relaxation of the rules by 1940.

[Wickham Green too]

2 hours ago, The Stationmaster said:

.... when you are writing an instruction you start with teh enginerring description of the parts, ....

I have written instructions - and I've always been careful to explain any pitfalls that could be encountered.

 

Anyway, we don't know why the Leading End buffers were different from the bog-standard Intermediate End buffers so cannot be sure that they retract by the same amount to leave the usual 3.5'' gap ....................... nor whether there was a risk of vertical disengagement - as described by Jim Snowdon on the last page - with no rubbing plate damping.

Experience with various electric and diesel-electric units would have shown whether rubbing plates were, indeed necessary by the time those Inter-City units were built - and they were still being fitted to new class 312 as late as 1977.

[Aire Head]

1 hour ago, Michael Hodgson said:

That was practice on some LMS branches, but I thought only where the gradients were limited. and then only on certain services nominated in the WTT (middle of the day rather than the peak commuter runs) and restricted to urgent traffic that couldn't wait till tomorrow's pick-up goods.  But the exigencies of WW2 might well have justified temporary relaxation of the rules by 1940.

 

I suspect so because it isn't in the 1947 general appendix meaning presumably any such allowance was probably in the sectional appendix for the Branchlines in question. As far as I can tell this wasn't a Midland Division thing as it doesn't appear in the Midland Division sectional appendix either though 🤷🏼‍♂️

 

Interesting though nonetheless!

[roythebus1]

The 312s used "standard" BR corridor connections and no buffers except on the outer ends which had rubbing plates and retractable buffers. Did the TP inter-city diesels have standard BR corridor connections throughout and retractable buffers? Did the Swindon IC units have standard BR corridor connections or pre-nationalisation smaller corridor connections which needed side buffers?

 

[jim.snowdon]

1 hour ago, Wickham Green too said:

I have written instructions - and I've always been careful to explain any pitfalls that could be encountered.

 

Anyway, we don't know why the Leading End buffers were different from the bog-standard Intermediate End buffers so cannot be sure that they retract by the same amount to leave the usual 3.5'' gap ....................... nor whether there was a risk of vertical disengagement - as described by Jim Snowdon on the last page - with no rubbing plate damping.

Experience with various electric and diesel-electric units would have shown whether rubbing plates were, indeed necessary by the time those Inter-City units were built - and they were still being fitted to new class 312 as late as 1977.

The important part is that those Inter-City units, ie the 124 & 126 sets, were built on the premise that they were full train sets - they would not be run in multiple with another complete set so the drawgear at the outer ends was provided only for shunting, dead movements and recoveries. The oddity was providing buckeyes on the outer ends of the 124s, but that may have been considered as a convenience when moving odd vehicles around in the depots given that the rest of the vehicles in the sets were buckeye coupled. In the end, they lost them, so it can't have been that much of a convenience.

 

[jim.snowdon]

12 minutes ago, roythebus1 said:

The 312s used "standard" BR corridor connections and no buffers except on the outer ends which had rubbing plates and retractable buffers. Did the TP inter-city diesels have standard BR corridor connections throughout and retractable buffers? Did the Swindon IC units have standard BR corridor connections or pre-nationalisation smaller corridor connections which needed side buffers?

 

The 123 and 124 sets did have retractable buffers and pullman gangways within the sets - https://www.rmweb.co.uk/topic/129641-class-124-dmu-trans-pennine-bogies-4mm-source/ , unlike the later EMU sets for the Southern Region.

 

[The Stationmaster]

5 hours ago, Aire Head said:

Interestingly I've seen in the 1940 dated supplement to the 1937 LMS General Appendix that a single Unfitted vehicle is allowed to be attached as the rear vehicle to a "local passenger" train provided a screw coupling is used.

 

I can only image the swinging effect on a typical 9ft wheelbase vehicle of the period!

 

3 hours ago, Aire Head said:

 

I suspect so because it isn't in the 1947 general appendix meaning presumably any such allowance was probably in the sectional appendix for the Branchlines in question. As far as I can tell this wasn't a Midland Division thing as it doesn't appear in the Midland Division sectional appendix either though 🤷🏼‍♂️

 

Interesting though nonetheless!

Despite what sounds like a very inviting authority it was only permitted 'where specially authorised' (in the relevant Sectional Appendix).  And judging by those GWR examples I have traced the number of places that happened was very limited indeed.  And if the line involved a rising gradient it was not normally permitted.

 

[Michael Hodgson]

9 hours ago, The Stationmaster said:

 

And if the line involved a rising gradient it was not normally permitted.

 

And a line with a falling gradient is of course one with a rising gradient if you were to allow such  trains to run in both directions. 

Very few lines are dead flat - even if you go to East Anglia!

[Aire Head]

9 hours ago, The Stationmaster said:

 

Despite what sounds like a very inviting authority it was only permitted 'where specially authorised' (in the relevant Sectional Appendix).  And judging by those GWR examples I have traced the number of places that happened was very limited indeed.  And if the line involved a rising gradient it was not normally permitted.

 

Oh its certainly something I won't be able to depict given my modelling of the Midland lines in Yorkshire!

[Wickham Green too]

12 hours ago, jim.snowdon said:

... The oddity was providing buckeyes on the outer ends of the 124s, but that may have been considered as a convenience when moving odd vehicles around in the depots given that the rest of the vehicles in the sets were buckeye coupled. In the end, they lost them, so it can't have been that much of a convenience. 

Indeed, not much of a convenience when the vast majority of locomotives or other units would not have been buckeye fitted

[The Stationmaster]

1 hour ago, Michael Hodgson said:

And a line with a falling gradient is of course one with a rising gradient if you were to allow such  trains to run in both directions. 

Very few lines are dead flat - even if you go to East Anglia!

Interestingly that was exactly the case in one example which I have come across on the GWR - only permitted in one direction.

[jim.snowdon]

6 hours ago, Wickham Green too said:

Indeed, not much of a convenience when the vast majority of locomotives or other units would not have been buckeye fitted

True, but I wonder if there were greater plans for 'main line' dmus that never came to fruition. Were the 126, then 123 and 124 fleets the start of a wider plan for the conversion of longer distance main line services to multiple unit operation, a change that eventually happened with the HST fleet and the later Voyager fleets. The 124s, as the last of the first generation dmus were a whole step ahead of anything that had gone before, bar the 123 sets , being designed to be flexible in their makeup, all the way to 12 car trains.

 

[TinTracks]

https://www.railcar.co.uk/topic/tail-loads/other-regions

Hi. There's a few interesting bits of info and pics on the attached link.

 Your thread jogged my memory of something I saw when I was a young 'un back in the 60's. I recalled seeing a two car DMU pulling a van that looked, to me, very similar to the old Hornby Dublo 4W Utility van at Redcar Central (Darlington to Saltburn Branch) . At that time I recall thinking it odd to see a SR van ''oopt north'' ( I know better now though!) Inspired by your thread I did a bit of searching and came up the above link. Crikey!! If you scroll down to the tales from the North Eastern it even gets a mention.

 Turns out a PMV was pulled by a two car DMU between Darlington/ Saltburn and Darlington/ Bishop Auckland. It also mentions a DMU pulling a fish van at Whitby Town.

     Hope you find the link of interest. Regards, Rich 

Edited April 4, 2023 by TinTracks

[jim.snowdon]

Looking for other dmu related matters turned up this example via wikipedia - taken in 1967 by Hugh Llewelyn - a class 128 parcels unit plus an ex-116 DMS converted for parcels use with three GUVs in tow on the way in to Paddington.

 

[russ p]

48 minutes ago, jim.snowdon said:

Looking for other dmu related matters turned up this example via wikipedia - taken in 1967 by Hugh Llewelyn - a class 128 parcels unit plus an ex-116 DMS converted for parcels use with three GUVs in tow on the way in to Paddington.

 

 

Is that in blue no yellow end or panels? 

[keefer]

looks like early-blue w/white roof domes, small numbers and yellow gangway shield.

Railcar has a WR Tail-loads booklet - relevant here is that DPU (2x230hp engines derated to 200hp) + DMU (2x150hp) has a maximum trailing load of 160t (except WLL) and 'special timings' between Paddington & Oxford (presumably to avoid delaying the Class 1 passenger services).

GUVs were 30t tare with max. load of 14t

https://www.railcar.co.uk/topic/tail-loads/wr-1968

[keefer]

13 minutes ago, russ p said:

 

Is that in blue no yellow end or panels? 

came up recently on another thread (can't remember which).

DPU at Didcot, 1967 (might actually be the same one as above):

Edited April 4, 2023 by keefer

[jim.snowdon]

50 minutes ago, russ p said:

Is that in blue no yellow end or panels? 

The notes with the original picture state blue, with yellow gangway covers, although they appear to be absolutely filthy.