Chains as a measurement.

[furnessvale]

We seem to cope with 1/2 packets of butter being 250g. And of course the sponge recipe of another poster is in ratios. Just the same in metric. Just don't mix up the systems.

I thought that, then it struck me that the 2 may be eggs. In which case we would also have to re-educate our hens to lay metric size eggs.

 

[InOban]

I believe that the standards for eggs (small/medium/large) are metric. I think a standard egg is 50g.
But we are a long way from chains! I think that sooner or later the railway will have to go metric. Having to teach new staff a system of measurement which they have never met before is a waste of time, and at risk of errors.

 

[Railsigns]

I think that sooner or later the railway will have to go metric.

It is the intention that this will take place as ETCS is rolled out across the network, although it has yet to be completed on the Cambrian lines (kilometre posts were installed at 500 m intervals but subsequently removed, leaving just the posts in place so that they can be easily reinstalled in the future).

 

[Mojo]

We seem to cope with 1/2 packets of butter being 250g. And of course the sponge recipe of another poster is in ratios. Just the same in metric. Just don't mix up the systems.

Absolutely. The 2-4-4-4 method for baking cakes also doesn’t take into account the fact that not all eggs are created equally! A far better method is to weigh the eggs (still with shell on) and use the same amount of sugar, butter and flour.

 

[najaB]

Elsewhere too. Standard wood sizes were long "four by two" (4 inches by 2 inches) for the larger pieces, or "two by one" (likewise)...

Except a 2x4 isn't 2 x 4 inches - it's 1 1/2 x 3 1/2.

https://en.wikipedia.org/wiki/Lumber#North_American_softwoods

 

[bearhugger]

Not the neatest thing...

View attachment 40005

Thanks for posting @kentuckytony

 

[Joseph_Locke]

Welcome sir not seen you posing for a while. A bike chain?

Sorry, communication now re-established following transfer of technology from Windoze to open source and forgot my forum password. It then took a WEEK to get it reset. And no, a proper, heavy, slightly rusty 22-yard-in-100-links chain

 

[edwin_m]

No other part of our economy has used anything other than metric for decades, except of course, for the need to convert road distances into miles.

It's actually very similar. All the designers will use metric measures but for the railway operators the speeds have to be expressed in miles per hour and the position along the route (which doesn't always align with distance) in miles and chains. This is for the very good safety-related reason that traincrews need to be presented with information in a consistent way (on signs and in the Sectional Appendix). Also the zero point from which those positions are measured is usually the one set originally by the Victorian builders, and the route the mileposts follow to get back to zero can provide some insights into railway history!

Historically, the Scottish Region used miles and chains, just like the rest of BR. In 1986, the Scottish Region went its own way and re-issued the Sectional Appendix with all measurements in miles and yards. As you've said, it has since reverted to miles and chains.

I'm comfortable with position being measured in miles and chains but the use of yards is confusing because a yard is so close to a metre.

Weight is a force measured in Newtons (SI).(Pedant Alert!)

Further pendant alert: newton, like all SI units, is given a small initial letter when spelt out in full.

 

[Joseph_Locke]

The railway already is metric, and has been since the early 70s like everyone else. We have a standing national exemption under EU law to display speeds in MPH, and a law on statute requiring mileposts (sic), but other than that - platforms are 915mm high, rails are 18.288m long, track gauge is 1435mm. The fact that those are cumbersome conversions of antiquated distances like 3 feet, 60 feet and 4 feet 8 and one half inches is purely co-incidental.

 

[InOban]

It occurs to me that with the universal adoption of GPS devices, there is little need to define a location as so many chains or metres from a signal or other datum point.

 

[Railsigns]

It occurs to me that with the universal adoption of GPS devices, there is little need to define a location as so many chains or metres from a signal or other datum point.

I can't imagine the location of a temporary speed restriction being specified in the weekly notice as a pair of GPS coordinates going down well with drivers.

 

[Dai Corner]

I can't imagine the location of a temporary speed restriction being specified in the weekly notice as a pair of GPS coordinates going down well with drivers.

Indeed. Which is easier to remember or write down (made up example)

Latitude: 51.559
Longitude: -3.006

Or 134m 17ch

 

[InOban]

I was assuming that the driver was provided with a device which could be remotely uploaded with the locations of TSRs etc. Less risk of transcription errors.

 

[Railsigns]

I was assuming that the driver was provided with a device which could be remotely uploaded with the locations of TSRs etc. Less risk of transcription errors.

Even so, a railway is linear in nature. A simple linear dimension is the most straightforward way to define a point along the railway.

 

[Ploughman]

And the battery cannot fail on a page of the latest notice on paper.

 

[cjmillsnun]

GPS has its own issues. No good in tunnels, not great in cuttings or anywhere out of LOS of the satellites. It's ideal for aviation as they tend to fly above anything that can get in the way.

Miles and chains is known by drivers and is ideal.

 

[cjmillsnun]

Cricket would be simpler in metric. 22 yards is 20.1168m and nobody would notice if the .1168 (less than 5 inches) was dropped.

It would make a difference as run outs would be harder.

 

[cjmillsnun]

I have access to the legacy as built cabling drawings for the Western and they're all in imperial measurements, some of them for the Swindon works go back to the 1940s, would be impossible to try and convert them to metric.

It wouldn't be impossible. It wouldn't be easy, but 1mm is a small enough measurement that any imperial measurement could be changed to mm. That said, I probably wouldn't bother.

 

[ComUtoR]

I can't imagine the location of a temporary speed restriction being specified in the weekly notice as a pair of GPS coordinates going down well with drivers.

Indeed. Which is easier to remember or write down (made up example)

Latitude: 51.559
Longitude: -3.006

Or 134m 17ch

Regardless of whatever its posted in. I still won't read them

And the battery cannot fail on a page of the latest notice on paper.

We are getting more and more notices digitally.

 

[Dai Corner]

And the battery cannot fail on a page of the latest notice on paper.

Out of interest, are cabs provided with facilities for charging mobile phones or tablets?

 

[InOban]

GPS is only one of the technologies which modern train control systems use to determine exact location. They could automatically slow the train for a TSR...

 

[InOban]

Out of interest, are cabs provided with facilities for charging mobile phones or tablets?

I read in another thread that drivers are expressly forbidden to use mobiles when driving.

 

[Dai Corner]

GPS is only one of the technologies which modern train control systems use to determine exact location. They could automatically slow the train for a TSR...

They could start, accelerate, maintain speed, decelerate and stop trains at predetermined locations too. But that's probably for another thread!

 

[Domh245]

GPS is only one of the technologies which modern train control systems use to determine exact location. They could automatically slow the train for a TSR...

I don't think GPS is accurate enough for a train to know which track it is on on a multi track approach (something like London Bridge for example) - if one line has a TSR and the others don't the train won't know if the TSR applies to it or not and slow down unnecessarily, reducing capacity. That (and other reasons) is why all the successful digital signalling systems use beacons or other fixed infrastructure to determine location instead of GPS

 

[MichaelWells]

I don't think GPS is accurate enough for a train to know which track it is on on a multi track approach

The Test Trains use GPS linked with a Tacho to know where it is, it can select the correct line even on multi track approaches, although sometimes does take the wrong route and it needing to be corrected. This is fine until you're working through the Thameslink Tunnels like I was last Night, and the system thinks your on the international platforms at St Pancras.

 

[Sunset route]

GPS is only one of the technologies which modern train control systems use to determine exact location. They could automatically slow the train for a TSR...

That’s assuming all the boards are the right order in the right place. The amount of times drivers report to me that TSR and ESR are incorrect positioned and you have to caution until they are corrected. We don’t even have miles and chains in our signalling centres let alone GPS references lol

 

[ComUtoR]

That’s assuming all the boards are the right order in the right place.

Or your new digital notice updates the latest ESR to 'WITHDRAWN' and you discover that it is still in place. :/

 

[Domh245]

The Test Trains use GPS linked with a Tacho to know where it is, it can select the correct line even on multi track approaches, although sometimes does take the wrong route and it needing to be corrected. This is fine until you're working through the Thameslink Tunnels like I was last Night, and the system thinks your on the international platforms at St Pancras.

By test trains, I assume you mean the 700s testing the ERTMS installation in the Thameslink Core as opposed to the 313? As far as I'm aware though, all ERTMS installations use Eurobalises to determine exact train position.

 

[MichaelWells]

By test trains, I assume you mean the 700s testing the ERTMS installation in the Thameslink Core as opposed to the 313? As far as I'm aware though, all ERTMS installations use Eurobalises to determine exact train position.

not quite. 73/9s and Mk2s.

 

[Stuart-h]

I'm fairly sure and I stand to be corrected when the railways were first built they had chain gangs. They used the chain as a set messured distance when the routes were being layed.