West Coast Railways Suspended (now reinstated)

[33056]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

Remington shavers?

 

[Sacro]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

George Foreman Lean Mean Fat-Reducing Grilling Machine?

 

[ac6000cw]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

I'm fairly sure it was either Remington or Gillette i.e. shavers/shaving products.

 

[DaleCooper]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

Victor Kiam, Remington

 

[MarkyT]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

Victor Kiam and the company he bought was Remington electric shavers.

 

[Pigeon]

I don't think anyone is suggesting that vacuum braked stock is unsafe, and as I pointed out above the improvement in stopping distance is down to disc brakes (which didn't arrive in any great numbers until Mk3 stock) not (as far as I know) the change from vacuum to air.

AIUI there is a difference between vacuum and air brake systems currently in use in the delay between braking demand and actual application becoming effective - italics to emphasise that it is not an inherent characteristic of vacuum or air that is involved, but a matter of how the systems are implemented. It arises from a combination of the pipe diameter used in relation to the volume of air that has to be moved to propagate the pressure change, and the means by which the pressure change causes application of the brakes - with vacuum it acts on the brake cylinders directly, whereas with air it operates a valve which connects the brake cylinders to atmosphere at the location of the valve itself. There is no inherent reason why a vacuum brake system could not be made with such a valve and with larger diameter pipework, it's just down to history that it's like that. The difference is only a matter of a few seconds and so is not significant except in very intensive working conditions. For extremely intensive working electro-pneumatic braking systems operate the local valve electrically to shave off a further few seconds, but retain the pressure operation as well as a backup.

Happy to be corrected by someone who actually works on the things

Does anyone care to share with the class or is this secret insider only knowledge?

Seconded... it is rather frustrating to keep reading "they did something mysterious which I can figure out but I'm not going to say what it is". If, as many posters have said, it is something which anyone who does drive steam trains on the main line will know about anyway, I can't see that it does any harm to satisfy the curiosity of those who don't.

At the moment I am guessing that the standard AWS/TPWS installation on a steam locomotive is badly designed in that it vents the brake pipe to atmosphere via a vent which is accessible from within the cab and can be blocked by stuffing a plastic bag or a hanky or something into it, thereby disabling the brake application without actually formally isolating the system. After all it wouldn't be the first time that a safety system has been designed on the assumption that people will not deliberately try to circumvent it - the thing with signalling systems having exposed electrical contacts allowing people to defeat the interlocking by shorting the contacts with a knife springs to mind - though I do find it surprising that such bad designs still make it into production these days.

 

[DaleCooper]

AIUI there is a difference between vacuum and air brake systems currently in use in the delay between braking demand and actual application becoming effective - italics to emphasise that it is not an inherent characteristic of vacuum or air that is involved, but a matter of how the systems are implemented. It arises from a combination of the pipe diameter used in relation to the volume of air that has to be moved to propagate the pressure change, and the means by which the pressure change causes application of the brakes - with vacuum it acts on the brake cylinders directly, whereas with air it operates a valve which connects the brake cylinders to atmosphere at the location of the valve itself. There is no inherent reason why a vacuum brake system could not be made with such a valve and with larger diameter pipework, it's just down to history that it's like that. The difference is only a matter of a few seconds and so is not significant except in very intensive working conditions. For extremely intensive working electro-pneumatic braking systems operate the local valve electrically to shave off a further few seconds, but retain the pressure operation as well as a backup.

I would think that the fact that a vacuum system can only work to a maximum (but unachievable) 1 atmosphere pressure differential also affects the theoretical relative performance of the two systems.

 

[HSTEd]

I believe they have an electro-vacuum system in use in South Africa. Apparently for historical reasons.

 

[Pigeon]

I would think that the fact that a vacuum system can only work to a maximum (but unachievable) 1 atmosphere pressure differential also affects the theoretical relative performance of the two systems.

Depends how big you make the brake cylinders. Available force depends on the pressure differential and on the square of the diameter of the cylinders. Hence vacuum brake cylinders are larger - which is a problem on Tube stock, but there is plenty of space on main line stock.

 

[Wolfie]

When I read this final part of your posting, I was mindful of a television advertisement many years ago in what I can just about remember as having an elderly American person who said that he enjoyed a product so much, that he bought the company. Can anyone recall what the product being advertised was?

"I'm Victor Kiam and I liked Remington razors so much that I bought the company..."

Victor Kiam, Remington

Victor Kiam and the company he bought was Remington electric shavers.

Beaten to it! Note to self - read to end before posting!

 

[Marklund]

When I was working in the industry just before its publication I was greatly impressed with the IAD Rail Systems HPSS product and recommended it for projects I was involved with, in line with Network Rail's national engineering guidelines.

Thanks a lot. :roll: Awful things.

 

[mcmad]

I was greatly impressed with the IAD Rail Systems HPSS product and recommended it for projects I was involved with, in line with Network Rail's national engineering guidelines. I understood, at the time that a frangible component was intended to be introduced.

No frangible component was produced for the HPSS sytem, as far as I am aware the only system with one is the Hydrive system currently used for NR60 and longer NR56 switches.

Since the first set of switches to be encounter had the route not been set would have been to run through the trailing (clamp lock fitted?) end of the switch diamond and then immediately the facing end, which would have been set diverging route then I doubt the outcome would be pretty even at low (sub 50mph) speed.

Thanks a lot. :roll: Awful things.

Indeed....

 

[Llama]

Which clearly wasn't enough in this case?

Wouldn't want to be saying that in my defense!

The fact that the AWS was made ineffective rather than isolated could in some ways be thought as being more damning of the driver.

 

[Jonfun]

It arises from a combination of the pipe diameter used in relation to the volume of air that has to be moved to propagate the pressure change, and the means by which the pressure change causes application of the brakes - with vacuum it acts on the brake cylinders directly, whereas with air it operates a valve which connects the brake cylinders to atmosphere at the location of the valve itself. There is no inherent reason why a vacuum brake system could not be made with such a valve and with larger diameter pipework, it's just down to history that it's like that.
Happy to be corrected by someone who actually works on the things

Hello, you called?

Unless you meant to say "release" rather than "application" of the brakes I'm afraid I don't think you correctly understand the vacuum, or indeed air brake system as it would be fitted to, say, Mk1 coaching stock - neither operate in the manner you describe.

On my phone at the moment but I'll happily explain the difference later on if needed.

Jon

 

[ilkestonian]

The fact that the AWS was made ineffective rather than isolated could in some ways be thought as being more damning of the driver.

It wasn't just the driver who was on the footplate.

Just saying...

 

[Elecman]

What difference does that make, the driver has sole responsibility for the train and its safety

 

[edwin_m]

That is an interesting if somewhat confusing document! When I was working in the industry just before its publication I was greatly impressed with the IAD Rail Systems HPSS product and recommended it for projects I was involved with, in line with Network Rail's national engineering guidelines. I understood, at the time that a frangible component was intended to be introduced.

The document states there is a risk but there is a very low probablity that non-frangibility could result in a 'permanent' derailment rather than just a 'wheel-jump' over the rails except possibly for very light weight vehicles, of which a Bullied pacific or for that matter an HST power car would not be examples. the overall risk of the run through occuring in the first place is significantly reduced by having TPWS (and TPWS+ where required at particularly high speed junctions) . . . hmmmm.

The problem with the document is that it is primarily part of a great exercise by RSSB to expunge the railway group standards series of all matters where only one duty holder is responsible, their revised terms of reference being now only to provide standards where separate organisations within the railway group have to cooperate to establish safety. Thus point run through is now in RSSB eyes a wholly NR issue and therefore following this 'impact assessment' there needs to be no further mention of it in current RGS documents. It is that process that has seen the entire signalling principles series of documents (amongst many others) withdrawn, to be replaced (no doubt) by a series of identical but internal Network Rail documents. The unfortunate side effect of this is that the current NR documents in their latest form are no longer publicly accessible, as were the RSSB series. At least the withdrawn documents are still available at RSSB but as an interested member of the public now I can no longer see any subsequent updates.

Thanks for the potted summary - and I agree with you the disappearing RGSs are a pain. In theory I have access to the NR standards via my employment, but it always seems much more difficult to find anything there than in RGS.

 

[ilkestonian]

What difference does that make, the driver has sole responsibility for the train and its safety

I simply think this condemnation of the driver before the facts are known is a little distasteful. Clearly something untoward appears to have happened given the information released by the RAIB, but until the full picture is known I don't think anyone should be acting as judge and jury.

 

[amcluesent]

It's my lads birthday next week and he's pestering me to buy a cowboy outfit. I said I didn't know West Coast Railways was up for sale...

 

[Pigeon]

Hello, you called?

Unless you meant to say "release" rather than "application" of the brakes I'm afraid I don't think you correctly understand the vacuum, or indeed air brake system as it would be fitted to, say, Mk1 coaching stock - neither operate in the manner you describe.

On my phone at the moment but I'll happily explain the difference later on if needed.

Jon

Ah - yes, when you're on a decent device, that would be great, thanks

Having been to look things up I think I was getting confused between some aspects of vacuum and air - I was thinking that air brakes, like vacuum brakes, "charged" both sides of the cylinder and then "discharged" one side of it to apply the brakes. On checking I find that they have a separate local reservoir which is connected via the magic valve to an uncharged brake cylinder to apply the brakes, and the cylinder is vented locally to atmosphere to release them. Is that more like? It makes sense in terms of what you say about applying vs. releasing. But I am still thinking that vacuum brakes rely on discharging the vacuum in the brake cylinders via the train pipe and the driver's brake valve, which seems to be at odds with what you're saying, so it would be handy to have the pukka explanation, thanks.

 

[E&W Lucas]

Seconded... it is rather frustrating to keep reading "they did something mysterious which I can figure out but I'm not going to say what it is". If, as many posters have said, it is something which anyone who does drive steam trains on the main line will know about anyway, I can't see that it does any harm to satisfy the curiosity of those who don't.

.

Please use a little common sense. There is no way any responsible railwayman is going to post the detail of how to bypass a safety system on a public railway forum, just for the amusement of enthusiasts. In fact, as has been shown above, it's not even common knowledge amongst those who have some knowledge of steam, and that's how it should be. It's knowledge I wish I didn't have, and I certainly won't be sharing it in detail.

Suffice is to say that there is a (improper) course of action, which if taken, will cause exactly the sequence of events with the AWS/ TPWS equipment, as described in the interim report. I can't think of anything else, which would do the same.

Re vacuum brakes, try getting your head around Direct Admission valves. Covered in the 1951 Manual for Enginemen.

To answer other above posts, vac brakes aren't used elsewhere on the network, that I can think of. There is no inherent problem with the system, it's more an issue of crew familiarity. Special certification required to work it.

 

[MarkyT]

Thanks for the potted summary - and I agree with you the disappearing RGSs are a pain. In theory I have access to the NR standards via my employment, but it always seems much more difficult to find anything there than in RGS.

Going back to Railtrack days, it was great when RSSB put all the RGSs on their website after responsibility for the documents was transferred out of the company. Prior to that, we only had access to them via the company CD, where the pdfs were protected against copying and pasting text. That meant if you were trying to write standards compliance statements in specs and correspondence, you had to find alternate means of quoting clauses from those standards. Either you had to manually re-type everything you wanted to quote or screen capture or print and scan for use with OCR (for which there was no company supplied facilities!). One particular large project actually paid a hacker to crack the disc as they had a complete new interlocking system to approve, they couldn't contemplate retyping every single word of the signalling related standards to input to a requirements management database system, and even a project of that significance could not persuade the internal standards publishers of the time to release an unprotected copy to them! The RSSB site changed all that releasing the files with copy protection removed. Sanity! There was a rumour that the RT contract/legal people were extremely paranoid about misquoted standards and insisted on the copy protection measure after some unscrupulous supplier had faked compliance for a product by maliciously misquoting a standard. I couldn't understand how copy protection could actually prevent someone determined to do that, but I know the policy made working life unnecessarily hard for everyone else honestly writing technical documents making reference to those standards.

 

[Llama]

It wasn't just the driver who was on the footplate.

Just saying...

No, but as stated above the driver has responsibility for the operation of the train.

The significant facts surrounding the incident were highlighted by the RAIB.

 

[cjmillsnun]

Please use a little common sense. There is no way any responsible railwayman is going to post the detail of how to bypass a safety system on a public railway forum, just for the amusement of enthusiasts. In fact, as has been shown above, it's not even common knowledge amongst those who have some knowledge of steam, and that's how it should be. It's knowledge I wish I didn't have, and I certainly won't be sharing it in detail.

Well said. Safety systems are there for a reason. I don't know how it was done, but I can make an educated guess as to the sort of thing that could do it. Needless to say I won't be sharing my thoughts.

If we are to find out how it was done, then that'll be through the RAIB report, although I will make another educated guess that they won't make those particular details public.

 

[alxndr]

Since the first set of switches to be encounter had the route not been set would have been to run through the trailing (clamp lock fitted?) end of the switch diamond and then immediately the facing end, which would have been set diverging route then I doubt the outcome would be pretty even at low (sub 50mph) speed

They are not clamplocks.

 

[Jonfun]

Ah - yes, when you're on a decent device, that would be great, thanks

Having been to look things up I think I was getting confused between some aspects of vacuum and air - I was thinking that air brakes, like vacuum brakes, "charged" both sides of the cylinder and then "discharged" one side of it to apply the brakes. On checking I find that they have a separate local reservoir which is connected via the magic valve to an uncharged brake cylinder to apply the brakes, and the cylinder is vented locally to atmosphere to release them. Is that more like? It makes sense in terms of what you say about applying vs. releasing. But I am still thinking that vacuum brakes rely on discharging the vacuum in the brake cylinders via the train pipe and the driver's brake valve, which seems to be at odds with what you're saying, so it would be handy to have the pukka explanation, thanks.

Vacuum brakes work, as the name suggests, by the locomotive's exhauster removing the air from the train's braking system to a pressure of between 21 and 25 inches of mercury below atmosphere (hereonin referred to as inHg) depending on the design of locomotive (ex GWR ones typically use 25 whereas anything else uses 21).
In each brake cylinder there are two sides, one (the reservoir) which is protected by a valve so that air can be removed but not re-enter, and the other which is maintained at the same pressure as the train pipe.
When both sides of the cylinder are at equal pressure (whether that be atmosphere, 25 inHg, or anywhere in between) then the brakes will be released.
We'll assume now that the locomotive has created a 21 inHg vacuum in the system.
To request a brake application, the driver (or Guard, or passenger via a Passcom cord) will open their valve which allows air into the system, which increases the pressure in the train pipe, let's say, to 13 inHg.
The train pipe is connected to a device on each cylinder called a DA (Direct Admission) Valve, which detects the increase in pressure and admits a proportional amount of air from outside - not the train pipe - to the brake cylinder.
Owing to the non-return valve we talked about earlier, the reservoir side of the cylinder remains at the same pressure (21 inHg), but the other side is higher (13 inHg), and it is this pressure differential which moves the brake apparatus to physically apply the brakes.
Releasing the brakes, the locomotive simply runs it's exhauster which removes the air from the train pipe and brake cylinders to return them all to a pressure of 21 inHg, thus there is no pressure differential and the brakes release.

You've pretty much nailed it now with regards to air brakes. The train pipe is charged to a high pressure and to apply the brake the pressure is reduced.
Each vehicle has an auxilary reservoir (charged from the main reservoir pipe where provided or via the train pipe where not), and subsequently a device called a distributor or triple valve (although I like the term "Magic Valve" so I'm going to steal that from now on ) in a similar way to the vacuum DA valve detects a drop in the train pipe pressure and then admits a proportional amount of air from the auxiliary reservoir into the brake cylinder; again there is a pressure differential acting in the brake cylinder which moves the apparatus to apply the brakes.
When the 'Magic Valve' detects the train pipe pressure is back to normal then the air is released from the cylinder returning both sides to atmosphere and thus releasing the brake.

 

[TDK]

The fact that the AWS was made ineffective rather than isolated could in some ways be thought as being more damning of the driver.

It wasn't the AWS it was the TPWS, read the report
--- old post above --- --- new post below ---

What difference does that make, the driver has sole responsibility for the train and its safety

And the company employing the driver has the responsibility to ensure they are competent to carry out their duties including training, notices, booking on procedures, fit for duty, monitoring fit for duty, ensuring the driver maintains route knowledge, supplying training for new systems and route amendments this list is just the tip of the iceberg

 

[Llama]

Thanks...

Both AWS and TPWS were made ineffective, so that brake demands from either would not actually apply the brakes, as stated in the report. The report doesn't say the TPWS temporary isolation switch was isolated, nor was the AWS full isolation switch isolated.

 

[E&W Lucas]

It wasn't the AWS it was the TPWS, read the report

Forget modern traction. What they did, would prevent either system from applying the brake. Initially, this was to release the application caused by the failure to cancel an AWS warning. This also made the subsequent TPWS intervention unable to apply the brakes physically.

 

[fergusjbend]

Well said. Safety systems are there for a reason. I don't know how it was done, but I can make an educated guess as to the sort of thing that could do it. Needless to say I won't be sharing my thoughts.

No need to. Its in Stephanie Browne's piece in this week's Rail.