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25 miles Carstairs to Edinburgh with no brakes?

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Posted (edited)

if the brake pipe is blocked by ice, or wet coal dust as happened to me once on an MGR, the brake will be isolated from the driver's control behind the blockage, but will eventually leak on as pressure is lost form the system, which is 'fail safe' in the sense that air pressure keeps the brakes off and they will apply themselves as the pressure falls.  This can take some time, though, more in general with air than with vacuum.

 

Two accidents to my knowledge, involving an up steel train running away down Beattock and colliding at high speed with a coal train entering Quintinshill up loop, 1970?, and a postal running away down Filton Bank ecs from Filton to Temple Meads, were caused by a failure to connect the brake pipes in the first place; the drivers simply set off with a train of isolated brakes.  Much is taken on trust; a crew relieving a train en route for example take the relieved crew's word for it that all is in order as stated on the signed load slips.  One would assume that staff are careful for their own safety at least, but assumptions are made and risks taken, fortunately rarely.

 

As for Mike's comment about it being an uphill struggle to impress upon staff in the 70s the need to carry out full continuity tests with air brakes, well, maybe at Radyr!  I can assure him that no train I picked up ever went anywhere unless I'd either carried out the test myself or had witnessed it being done, and neither did any train I was working that had had the continuity destroyed at any time, vacuum or air.  I do not recall anyone ever criticising or discouraging me from doing this, no matter how late we were!

Edited by The Johnster
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3 minutes ago, The Johnster said:

if the brake pipe is blocked by ice, or wet coal dust as happened to me once on an MGR, the brake will be isolated from the driver's control behind the blockage, but will eventually leak on as pressure is lost form the system, which is 'fail safe' in the sense that air pressure keeps the brakes off and they will apply themselves as the pressure falls.  This can take some time, though, more in general with air than with vacuum.

 

Two accidents to my knowledge, involving an up steel train running away down Beattock and colliding at high speed with a coal train entering Quintinshill up loop, 1970?, and a postal running away down Filton Bank ecs from Filton to Temple Meads, were caused by a failure to connect the brake pipes in the first place; the drivers simply set off with a train of isolated brakes.  Much is taken on trust; a crew relieving a train en route for example take the relieved crew's word for it that all is in order as stated on the signed load slips.  One would assume that staff are careful for their own safety at least, but assumptions are clearly sometimes made and risks taken, fortunately rarely.

 

As for Mike's comment about it being an uphill struggle to impress upon staff in the 70s the need to carry out full continuity tests with air brakes, well, maybe at Radyr!  I can assure him that no train I picked up ever went anywhere unless I'd either carried out the test myself or had witnessed it being done, and neither did any train I was working that had had the continuity destroyed at any time, vacuum or air.  I do not recall anyone ever criticising or discouraging me from doing this, no matter how late we were, except at Margam which was always a bit of a struggle in terms of train preparation...

 

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54 minutes ago, The Stationmaster said:

You used to have to do it more often during freezing weather (Caradoc's post also refers).

 

I must say though that in my experience the running brake test rule was often honoured more in the breach than the observance.

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14 minutes ago, The Johnster said:

if the brake pipe is blocked by ice, or wet coal dust as happened to me once on an MGR, the brake will be isolated from the driver's control behind the blockage, but will eventually leak on as pressure is lost form the system, which is 'fail safe' in the sense that air pressure keeps the brakes off and they will apply themselves as the pressure falls.  This can take some time, though, more in general with air than with vacuum.

 

Two accidents to my knowledge, involving an up steel train running away down Beattock and colliding at high speed with a coal train entering Quintinshill up loop, 1970?, and a postal running away down Filton Bank ecs from Filton to Temple Meads, were caused by a failure to connect the brake pipes in the first place; the drivers simply set off with a train of isolated brakes.  Much is taken on trust; a crew relieving a train en route for example take the relieved crew's word for it that all is in order as stated on the signed load slips.  One would assume that staff are careful for their own safety at least, but assumptions are made and risks taken, fortunately rarely.

 

As for Mike's comment about it being an uphill struggle to impress upon staff in the 70s the need to carry out full continuity tests with air brakes, well, maybe at Radyr!  I can assure him that no train I picked up ever went anywhere unless I'd either carried out the test myself or had witnessed it being done, and neither did any train I was working that had had the continuity destroyed at any time, vacuum or air.  I do not recall anyone ever criticising or discouraging me from doing this, no matter how late we were!

 

One of my former Control colleagues had worked with the guy responsible for preparing the steel train involved in the Quintinshill accident; Suffice to say his opinion of that man is not printable, even with the use of asterisks for every letter (I believe staff were killed in that crash).

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37 minutes ago, The Johnster said:

if the brake pipe is blocked by ice, or wet coal dust as happened to me once on an MGR, the brake will be isolated from the driver's control behind the blockage, but will eventually leak on as pressure is lost form the system, which is 'fail safe' in the sense that air pressure keeps the brakes off and they will apply themselves as the pressure falls.  This can take some time, though, more in general with air than with vacuum.

 

Two accidents to my knowledge, involving an up steel train running away down Beattock and colliding at high speed with a coal train entering Quintinshill up loop, 1970?, and a postal running away down Filton Bank ecs from Filton to Temple Meads, were caused by a failure to connect the brake pipes in the first place; the drivers simply set off with a train of isolated brakes.  Much is taken on trust; a crew relieving a train en route for example take the relieved crew's word for it that all is in order as stated on the signed load slips.  One would assume that staff are careful for their own safety at least, but assumptions are made and risks taken, fortunately rarely.

 

As for Mike's comment about it being an uphill struggle to impress upon staff in the 70s the need to carry out full continuity tests with air brakes, well, maybe at Radyr!  I can assure him that no train I picked up ever went anywhere unless I'd either carried out the test myself or had witnessed it being done, and neither did any train I was working that had had the continuity destroyed at any time, vacuum or air.  I do not recall anyone ever criticising or discouraging me from doing this, no matter how late we were!

All I will say is that I worked at a lot more places than Radyr and unlike Radyr most of those places dealt with fully fitted trains of one sort or another.  On one interesting occasion in the early '80s when I was passenger shunting during an unofficial strike at a well known London terminus often associated with bear I was a little surprised by how many Drivers told me 'we don't bother with the Continuity Test on air brake trains mate, nothing's happened to the train since it came in.'  

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49 minutes ago, caradoc said:

 

One of my former Control colleagues had worked with the guy responsible for preparing the steel train involved in the Quintinshill accident; Suffice to say his opinion of that man is not printable, even with the use of asterisks for every letter (I believe staff were killed in that crash).

That was the one where someone connected the through pipes (and only the through pipes) on a rake of air-braked, vac-piped, SAB wagons going from Ravenscraig to Trostre, wasn't it? There was also a case of a passenger train on the WCML where a blanking plug was wedged in the main air-pipe, effectively make the train unfitted.

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53 minutes ago, caradoc said:

 

One of my former Control colleagues had worked with the guy responsible for preparing the steel train involved in the Quintinshill accident; Suffice to say his opinion of that man is not printable, even with the use of asterisks for every letter (I believe staff were killed in that crash).

The driver and guard of the steel train, who were of course also culpable to an extent, and the guard of the coal train, were killed instantly; it is not pleasant to dwell on what they must have felt in the final moments.  

 

My feelings about the train preparer are probably in line with your colleague’s. 

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2 hours ago, The Johnster said:

if the brake pipe is blocked by ice, or wet coal dust as happened to me once on an MGR, the brake will be isolated from the driver's control behind the blockage, but will eventually leak on as pressure is lost form the system, which is 'fail safe' in the sense that air pressure keeps the brakes off and they will apply themselves as the pressure falls.  This can take some time, though, more in general with air than with vacuum.

 

Two accidents to my knowledge, involving an up steel train running away down Beattock and colliding at high speed with a coal train entering Quintinshill up loop, 1970?, and a postal running away down Filton Bank ecs from Filton to Temple Meads, were caused by a failure to connect the brake pipes in the first place; the drivers simply set off with a train of isolated brakes.  Much is taken on trust; a crew relieving a train en route for example take the relieved crew's word for it that all is in order as stated on the signed load slips.  One would assume that staff are careful for their own safety at least, but assumptions are made and risks taken, fortunately rarely.

 

As for Mike's comment about it being an uphill struggle to impress upon staff in the 70s the need to carry out full continuity tests with air brakes, well, maybe at Radyr!  I can assure him that no train I picked up ever went anywhere unless I'd either carried out the test myself or had witnessed it being done, and neither did any train I was working that had had the continuity destroyed at any time, vacuum or air.  I do not recall anyone ever criticising or discouraging me from doing this, no matter how late we were!

It is possible even the situation with ice in the brake pipe that the pelage can be so slow as even when all the air has leaked off that the brakes will not apply as the control chamber will have leaked off also.........

 

 

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Posted (edited)
5 hours ago, martin_wynne said:

It's interesting that a safety alert has been issued to the industry reminding staff to do brake continuity tests. That's seems a bit fundamental to me -- like a reminder not to pass signals at danger.

 

Martin.

 

The exact RAIB wording is:

 

"The train operator issued a safety alert to the industry on 5 August 2019 (NIR 3350/224) reminding railway staff of the importance of carrying out the brake continuity test after all other train preparation activities"

 

My italics.  That suggests to me that they did do a brake test and then someone shut the valve afterwards.

Edited by DY444
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1 hour ago, DY444 said:

 

The exact RAIB wording is:

 

"The train operator issued a safety alert to the industry on 5 August 2019 (NIR 3350/224) reminding railway staff of the importance of carrying out the brake continuity test after all other train preparation activities"

 

My italics.  That suggests to me that they did do a brake test and then someone shut the valve afterwards.

The RAIB report should, in due course, be interesting reading as to the actual sequence of events, so long as all of the staff concerned are absolutely open and honest about it.

 

Jim

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7 hours ago, The Stationmaster said:

On one interesting occasion in the early '80s when I was passenger shunting during an unofficial strike at a well known London terminus often associated with bear I was a little surprised by how many Drivers told me 'we don't bother with the Continuity Test on air brake trains mate, nothing's happened to the train since it came in.'  

 

That kind of thing can put you in an 'interesting' position. I have been told to ignore procedures which I understood were safety-related. When I insisted on carrying them out, I have had to deal with reactions up to and including threats of violence.

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5 hours ago, DY444 said:

 

The exact RAIB wording is:

 

"The train operator issued a safety alert to the industry on 5 August 2019 (NIR 3350/224) reminding railway staff of the importance of carrying out the brake continuity test after all other train preparation activities"

 

My italics.  That suggests to me that they did do a brake test and then someone shut the valve afterwards.

 

 

It is worth reminding folk on here that the CS Mk5s are fitted with Dellner couplings on each end - the first coaching stock in the UK so fitted.  This means that unlike traditional coaching stock where the shunter connects the red and yellow pipes, shackle and ETH cables, CS Mk5s are coupled with the dellners, and the shunter "merely" couples the ETS cables and the 61 pin jumper. The air pipe connections are "made" through the coupler head like moat modern multiple units.

 

Apart from the CS staff and RAIB, the rest of us don't know what happened a Carstairs that morning, and it isn't really healthy to speculate. The RAIB report will tell us in the fullness of time. It is perhaps fortunate that the driver of 1B26, the signaller and the Train Manager had the presence of mind to interact.  I was on duty that morning in a "neighbouring" TOC Control office and it was quite scary to watch the events unfold through phone calls and log messages. Fortunately our crew and trains were safe and we can only speculate (if we feel the need to) until the RAIB report is published. 

 

    

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1 hour ago, pH said:

 

That kind of thing can put you in an 'interesting' position. I have been told to ignore procedures which I understood were safety-related. When I insisted on carrying them out, I have had to deal with reactions up to and including threats of violence.

In the 1980s I was put down in front of my staff by a very senior manager and member of the signal engineering profession. He told me the procedure I was using to produce designs for signalling alterations was time and money wasting and was to be stopped immediately. After he left the office I told the staff to carry on as normal and ignore what he had said. They agreed with my position and carried on as before. Shortly after during what I considered to be a reorganisation too far I engineered myself a move to a different job. Less than 12 months later Clapham happened and suddenly the methods we had been using were flavour of the season. 

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As someone who was a passenger on this very service, I'm very much looking forward to seeing what the RAIB find. The seriousness of what was happening didn't fully hit until we'd cleared the platforms at Waverley and the Train Manager was running through the corridor to his cabin to bring the train to a halt. There was then a rather animated 'discussion' between him and the driver after we'd stopped within Calton Tunnel.

 

It was my first journey on CS, and what a journey it was! The coaches seem quite smart when you step on, but the seats are really uncomfortable and don't recline enough. The ride quality was hit and miss, with several instances throughout the night where you could hear and feel the bogies not coping very well with whatever trackwork it was running over. There was one point where I thought we'd come off the track it was that bad! The older stock we got from Fort William a few days later was pretty ratty inside but was far more comfortable, except for the lack of A/C making it a sweatbox.

 

There was a delay leaving Carstairs, which seemingly was due to issues trying to get the ETH cable in. The hostest from the lounge car came through and was talking to the TM or Shunter about there being no power in the kitchen to prepare breakfast. The staff (3 of them) all seemed stressed out, even before leaving London and were a touch rude at times.

 

To me, CS seemed to play down the severity of the incident. I think they were lucky the incident didn't wind up being a test of how crashworthy the MK5's are.

 

Andy.

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Posted (edited)
11 hours ago, Covkid said:

 

 

It is worth reminding folk on here that the CS Mk5s are fitted with Dellner couplings on each end - the first coaching stock in the UK so fitted.  This means that unlike traditional coaching stock where the shunter connects the red and yellow pipes, shackle and ETH cables, CS Mk5s are coupled with the dellners, and the shunter "merely" couples the ETS cables and the 61 pin jumper. The air pipe connections are "made" through the coupler head like moat modern multiple units.

 

Apart from the CS staff and RAIB, the rest of us don't know what happened a Carstairs that morning, and it isn't really healthy to speculate. The RAIB report will tell us in the fullness of time. It is perhaps fortunate that the driver of 1B26, the signaller and the Train Manager had the presence of mind to interact.  I was on duty that morning in a "neighbouring" TOC Control office and it was quite scary to watch the events unfold through phone calls and log messages. Fortunately our crew and trains were safe and we can only speculate (if we feel the need to) until the RAIB report is published. 

 

    

This is really useful.

 

I have no direct experience of Dellner couplers. Do the air connections self seal when commanded to part or do you still rely on isolating cocks?

 

Edit because the original question was really stupid.

Edited by david.hill64
Stupid original question

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11 hours ago, Covkid said:

 

 

It is worth reminding folk on here that the CS Mk5s are fitted with Dellner couplings on each end - the first coaching stock in the UK so fitted.  This means that unlike traditional coaching stock where the shunter connects the red and yellow pipes, shackle and ETH cables, CS Mk5s are coupled with the dellners, and the shunter "merely" couples the ETS cables and the 61 pin jumper. The air pipe connections are "made" through the coupler head like moat modern multiple units.

 

Apart from the CS staff and RAIB, the rest of us don't know what happened a Carstairs that morning, and it isn't really healthy to speculate. The RAIB report will tell us in the fullness of time. It is perhaps fortunate that the driver of 1B26, the signaller and the Train Manager had the presence of mind to interact.  I was on duty that morning in a "neighbouring" TOC Control office and it was quite scary to watch the events unfold through phone calls and log messages. Fortunately our crew and trains were safe and we can only speculate (if we feel the need to) until the RAIB report is published. 

 

    

 

I appreciate that but the stock still has a brake pipe isolation valve as the RAIB statement explicitly states:

 

"The train comprised eight Mark 5 coaches hauled by a Class 92 electric locomotive that had been attached at Carstairs. On the approach to Edinburgh the driver discovered that his train’s braking performance was well below normal. The RAIB’s preliminary investigation indicates that he had no control of the brakes on the coaches because a brake pipe isolating valve was in the closed position when the train left Carstairs station. This meant that the only effective brakes on the train as it approached Edinburgh were those on the locomotive, which were insufficient to maintain control of the train. The train was brought to a stand by the operation of an emergency device in one of the coaches by the Train Manager, which caused the train brakes to apply."

 

It is therefore not in doubt that the brake pipe isolation valve was closed and the only element of speculation in my post was my suggestion, based on the wording of the paragraph about the industry bulletin, that a brake test was probably carried out and the valve closed afterwards.  As I see it there are only two possibilities; a brake test was done and the valve closed afterwards or a brake test was not done at all.  

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7 hours ago, david.hill64 said:

This is really useful.

 

I have no direct experience of Dellner couplers. Do the air connections self seal when parted or do you still rely on isolating cocks?

The air reservoir connection is normally self sealing, just as it is with conventional pipes, as it is not a critical part of the brake system should the coupling part. The brake pipe connection, if this stock has one, is trickier, as with the Westinghouse type automatic air brake, it must not be self sealing in order for the brake to be automatically applied, but it has to be capable of being closed off at the ends of the train, hence on conventional pipes it has to have a cock. The purpose of the brake pipe continuity test is to confirm that not only are all the brake pipes connected but also that all the brake pipe cocks have been opened, making the pipe continuous.

 The Westinghouse type air brake is not universal, particularly on more modern multiple unit stock, where the air brake may be electrically controlled, with train integrity proved by a round the train circuit, usually through the coupler's electrical connections. Even then, this has to be automatically terminated at the back of the train and with hands-free coupling and uncoupling, ie without the use of manually operated switches, care has to be taken in the design of the electrical equipment to prevent the parted ends of the train automatically reconfiguring if the coupling parts (and Scharfenberg couplings have been known to part in service).

Of the Caledonian Sleeper stock, all I know is that they have Scharfenberg couplings. The detail of the brake control arrangements are not in the public domain.

 

Jim

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16 minutes ago, jim.snowdon said:

The air reservoir connection is normally self sealing, just as it is with conventional pipes, as it is not a critical part of the brake system should the coupling part. The brake pipe connection, if this stock has one, is trickier, as with the Westinghouse type automatic air brake, it must not be self sealing in order for the brake to be automatically applied, but it has to be capable of being closed off at the ends of the train, hence on conventional pipes it has to have a cock. The purpose of the brake pipe continuity test is to confirm that not only are all the brake pipes connected but also that all the brake pipe cocks have been opened, making the pipe continuous.

 The Westinghouse type air brake is not universal, particularly on more modern multiple unit stock, where the air brake may be electrically controlled, with train integrity proved by a round the train circuit, usually through the coupler's electrical connections. Even then, this has to be automatically terminated at the back of the train and with hands-free coupling and uncoupling, ie without the use of manually operated switches, care has to be taken in the design of the electrical equipment to prevent the parted ends of the train automatically reconfiguring if the coupling parts (and Scharfenberg couplings have been known to part in service).

Of the Caledonian Sleeper stock, all I know is that they have Scharfenberg couplings. The detail of the brake control arrangements are not in the public domain.

 

Jim

Yes I realised my question was stupid: I should have asked if they are self sealing in a commanded separation. Clearly in an uncommanded separation they must not seal! I will edit!

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Posted (edited)
24 minutes ago, jim.snowdon said:

The air reservoir connection is normally self sealing, just as it is with conventional pipes, as it is not a critical part of the brake system should the coupling part. The brake pipe connection, if this stock has one, is trickier, as with the Westinghouse type automatic air brake, it must not be self sealing in order for the brake to be automatically applied, but it has to be capable of being closed off at the ends of the train, hence on conventional pipes it has to have a cock. The purpose of the brake pipe continuity test is to confirm that not only are all the brake pipes connected but also that all the brake pipe cocks have been opened, making the pipe continuous.

 The Westinghouse type air brake is not universal, particularly on more modern multiple unit stock, where the air brake may be electrically controlled, with train integrity proved by a round the train circuit, usually through the coupler's electrical connections. Even then, this has to be automatically terminated at the back of the train and with hands-free coupling and uncoupling, ie without the use of manually operated switches, care has to be taken in the design of the electrical equipment to prevent the parted ends of the train automatically reconfiguring if the coupling parts (and Scharfenberg couplings have been known to part in service).

Of the Caledonian Sleeper stock, all I know is that they have Scharfenberg couplings. The detail of the brake control arrangements are not in the public domain.

 

Jim

The brake pipe isolating cock is the low mounted valve on a horizontal pipe immediately to the left of the bottom of the gangway - it was discussed some time back in another thread when I wondered what it was and expressed concern about it being mounted so low down.  It is visible, in the closed position in the photo linked below. (which was originally linked in the Caledonian Sleeper thread).   The isolating cock is approximately level with the bottom of the gangway to the left of it and vertically below the ETH female connector.  It is in the closed position in the photo linked below and is clearly visible if you click on the link or v can otherwise enlarge the photo. incidentally the phoy to shows a test run, nota. train in public service.  I understand from conversation with another forum member who confirmed that it is the Brake Pipe isolating cock that the letters 'BPIC' indicate 'Brake Pipe Isolating Cock' .

 

What is not clear is whether or not the air pipes through the Dellner coupler heads self seal when they are on the rear vehicle although - I'm told - it is probable that they do and that if a breakaway occurs there is a mechanism in the coupling which prevents them self sealing.  Perhaps the RAIB Report will clarify that one way or the other unless any other members of the forum have more complete information on this aspect. 

 

PS. I've just remembered that having observed Class 387 splitting it would appear that the couplings self seal on a planned separation of vehicle (unless there is an isolating valve controlled from the cab?).

 

3) 15002 at Dumbarton Central on 18th April 2018

 

Edited by The Stationmaster
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If the RAIB are happy to release information that the train set off with the brakes isolated, then that's probably what happened, and reminders about the importance of brake checks are pertinent (but don't actually tell us anything more about what happened).

 

What really matters as far as preventing a repeat is why that happened, and all there is in the public domain on that score at present is uninformed speculation. We will no doubt find out when the full report is published.

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1 hour ago, The Stationmaster said:

The brake pipe isolating cock is the low mounted valve on a horizontal pipe immediately to the left of the bottom of the gangway - it was discussed some time back in another thread when I wondered what it was and expressed concern about it being mounted so low down.  It is visible, in the closed position in the photo linked below. (which was originally linked in the Caledonian Sleeper thread).   The isolating cock is approximately level with the bottom of the gangway to the left of it and vertically below the ETH female connector.  It is in the closed position in the photo linked below and is clearly visible if you click on the link or v can otherwise enlarge the photo. incidentally the phoy to shows a test run, nota. train in public service.  I understand from conversation with another forum member who confirmed that it is the Brake Pipe isolating cock that the letters 'BPIC' indicate 'Brake Pipe Isolating Cock' .

 

What is not clear is whether or not the air pipes through the Dellner coupler heads self seal when they are on the rear vehicle although - I'm told - it is probable that they do and that if a breakaway occurs there is a mechanism in the coupling which prevents them self sealing.  Perhaps the RAIB Report will clarify that one way or the other unless any other members of the forum have more complete information on this aspect. 

 

PS. I've just remembered that having observed Class 387 splitting it would appear that the couplings self seal on a planned separation of vehicle (unless there is an isolating valve controlled from the cab?).

 

https://mark5812.smugmug.com/UKpicturesclassorder/Rolling-Stock/i-p45ktvB/A

 

Thank you, just the picture needed to answer the question.

 

Preventing the automatic reconfiguring of these types of couplers is an interesting subject, and one I had to deal with in my time on the DLR with the B stock. London Underground were amongst the first (if not the first) to adopt automatic couplers with the 1935 stock, and their solution to the problem was the coupling "engine", which would usually be located inside the offside of the cab. That worked by the person doing the (un)coupling having to manually operate a rotary switch that both shut off the brake pipe and dealt with any round train circuits, such as the door interlock circuit. That principle was still in use on the D78 stock (the last LU stock where I had much to do with the control wiring), with the only real difference being that the train continuity, and thus the brakes, were proved electrically instead of pneumatically. (After the 1972 stock, subsequent stocks had the Westcode EP brake equipment instead of the previous EP/Westinghouse systems.)

The DLR B90 stock presented more of a problem as it had been designed to allow for (un)coupling to be done using just a push button on the driver's desk and, as I discovered during the design approval process, if the coupler parted unintentionally, the control relays would automatically reconfigure to an end of train state. Between myself and the BN design engineers, that got rearranged with a number of cross-coupler feeds (so that if mechanical continuiy was lost, certain relays could not be fed) and a latching relay.

I can't comment on the 387s, but from observation it does require actions to be undertaken in both cabs, as was also the case with the BSI couplers on the 165/166 fleet before them.

 

Jim

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Posted (edited)

This is the pic (linked to in another thread) that Mike (Stationmaster) referred to:

End details of 15008 ( 967000150086 ), SC-008, a Caledonian Sleeper 8 seated 7 - 1, CAF Mk5 coach, seen at Carlisle Citadel Station.

(c) Ray Forster on Flickr

 

Isolating valve visible on LHS, below the 3 jumper cables.

Edited by keefer
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17 hours ago, SWT442 said:

 

It was my first journey on CS, and what a journey it was! The coaches seem quite smart when you step on, but the seats are really uncomfortable and don't recline enough. The ride quality was hit and miss, with several instances throughout the night where you could hear and feel the bogies not coping very well with whatever trackwork it was running over. There was one point where I thought we'd come off the track it was that bad! The older stock we got from Fort William a few days later was pretty ratty inside but was far more comfortable, except for the lack of A/C making it a sweatbox.

Crewe always feels like that, on any stock at slow speed.

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Wondering if that BPIC has a similar function to the Main Res Pipe Isolating Cock on a unit, to isolate the air connection on an auto coupler

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Posted (edited)

Disclaimer - I'm a shunter but I've never dealt with Caledonian sleeper stock. Personally speaking I think the Dellner on hauled stock is an unnecessary complication and nothing is wrong with two pipes and a screw or buckeye coupling 

 

Two things immediately jump out looking at the picture on Flickr that Keefr posted a link to.

1) compare the two air pipe holes in the coupler head. Bottom one (presumed main res) has a brass fitting, akin to the star valve to self seal on the yellow main res pipe on a traditional air pipe setup. Top hole doesn't have this, so on that logic, the top hole (brake pipe) isn't self sealing.

2) on logic of 1), the red cock seals the brake pipe to allow 5 bar to be created and the brakes released. If this is so, it appears a brake test is completed by opening this cock and allowing the pipe to fall to zero through the upper hole in the coupler.

 

If the RAIB have said the brakes were isolated and the loco had no control of the brake, then it is a possibility that a brake test was completed, but the air that was expelled was that which was trapped in the coaches, between the cocks at each end of the set. It is for this reason, that when doing a brake test, it's advisable to wait for the air to blow back through to ensure that the pipe between stock and loco is connected and taps open correctly.

 

Please note, I am not saying this is what happened or trying to imply blame, but trying to show a bit of light on brake test procedure. 

 

Mention has been made of taps that need to be squeezed to open and close them. A lot of recent wagons have European standard cocks, which have done away with the need to squeeze and instead are heavily sprung. This springing makes them a lot harder to open in a controlled manner and the lack of tab to squeeze also means there's a risk of them closing in traffic.

 

Jo

Edited by Steadfast
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