Brighton Atlantic: 32424 Beachy Head

As I understand, slightly crossed wires. The issue is from the Bluebell Railway Trust, who would support the project financially, not the BRPS. Quite properly, for a project such as this that has a long duration and high cost, there are checks in place to ensure it is likely to be viable in funding and people; I think this is just a reflection of those checks taking place. That all feels proper to me: I am sure that like many I would love to see an E class built, but absolutely don't want to see half an E class abandoned somewhere. The same checks would be in place for any proposed project of that scale.

Tom

 

Tom, as always, a very helpful response and as you say, robust due diligence and careful planning is the right thing to be doing. As always, press articles need to be taken with a pinch of salt. The E class strategy has some sound thinking behind it and I will be supporting it as and when it goes through its relevant approval processes.

 

I suspect its probably not sensible to "ratify" it until the project is at a stage where such action is necessary.

 

One thing I suspect the Trust may be considering as well is thus, is there an actual enthusiasm out there enough to sustain this project or indeed start it? I only suggest this as it would seem to me the Atlantic team speak of keenness to do this sure, but have they actually considered if other people are so keen?

I get the impression on here on this forum for example, quite a few people seemed put off by the idea, as many were hoping for the team to do the K Class Mogul next. Plus another issue I've noticed people take with this idea, is the E Class just doesn't seem that striking and interesting enough an engine to build a replica for.

Now personally I wouldn't be against a E Class being built, although I will admit it doesn't appeal to me appearance wise as others would. A part of me actually would have liked them to build another D Class honestly, as it's all pretty clear the one in the national collection won't be running again, and as it's the most well known and well regarded of the SECR passenger locos it just makes more sense to me to build another one to be actually used.

I mean come on, who wouldn't want to see a D Class on the Bluebell? A perfect match I'd say.

 

Out of curiosity, is anybody involved with the project able to explain the design rationale behind the loco having an air system and air assisted reverser? From my understanding of a recent conversation, the loco in original form (and subsequently the new build) is not able to work an air braked train which seems a bit odd given the pneumatic complexity of the loco.

 

Errrr ..... What with the LBSC being using the Westinghouse system, I'm confused. Are we speaking of the putative SECR E?

Time for a dedicated thread for the reanimation of Mr Wainwright's fine design? What say you, folks?

 

I'm wondering if its because the was no space for a vac brake cylinder, so a smaller air braked one was substituted?

 

If you did not have enough space for a vac pot, perhaps you could use a steam brake on the loco?


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It doesn't matter what you could do, my query is in relation to what is there! While drawings exist for many things, what is not recorded typically recorded is the decisions behind the various design choices that were made.

 

Not sure I am quite following the question - as I understand, it is air braked with an air-assisted reverser because that is what the original had.

@Grashopper will undoubtedly know better than me the intricacies I’d modern air-braked trains: my understanding is that the loco would be able to haul a train fitted with the single air pipe system (as on the Isle of Wight) but there is no provision for the modern two pipe system. (Just wondering if that is the source of the comment about “not being able to haul air braked trains”?)

Tom

 

Tom, was at the end of an RF shift so I was tired... pretty sure "they" said it would not be able to work charter stock, but no mention of single pipe stock so you may well be correct. Not that Bluebell currently has any single piped air braked coaches (although it is in the LTP to have a set of Brighton air braked coaches)

 

I believe the restriction is that it won’t be able to work charter stock, but it could work single pipe air braked stock if any existed.

Tom

 

This link seems to suggest in the last paragraph of the 4th from last section that a single piped loco can work with twin piped stock.

http://www.railway-technical.com/trains/rolling-stock-index-l/train-equipment/brakes/

Is this a correct interpretation?

 

IIRC, dual pipe air brakes ( red & yellow pipes) were fitted to freight stock in the early days, but the through reservoir pipe ( yellow) was disconnected. The actual braking pipe is the red pipe, and therefore modern carriage stock will still have brakes that operate on just the red pipe. At low speeds on heritage railways, the use of just the single red pipe is ample, it is just that the reservoirs are back-filled from the train pipe. Also bear in mind that modern stock uses distributors for operating the brakes, whereas the IOW (and London transport I think) use the original style Triple Valves.

EP brakes ( most Southern EMU's & DEMU's ) have extra bits added for electrical control of the release, but the basis is still the single red pipe....

 

My understanding as someone with virtually no air brake experience is that a single pipe will work dual pipe stock but the graduable element of the dual pipe system is no longer available. With a single pipe system you can apply the brake gradually but you cannot release gradually. Repeated application of the brake will also deplete the reservoir pressure if it does not have time to recharge between applications.

 

That is my understanding as well.

 

My understanding is subtly different. The graduated release function on distributors works based on a reference pressure, set from the peak train pipe pressure with a non-return valve. This is completely independent of the main reservoir pipe, which is charging the auxiliary reservoirs at all times its pressure exceeds theirs. The reservoir pipe has no effect on the functioning of the system, except that you'll get more applications without emptying the reservoirs and, when it's at 100psi, faster applications.

Where running a 'classic' Westinghouse engine with a modern dual pipe train may prove awkward, is that the classic brake vale is arranged for graduated application, but not graduated release, so accurately controlling a rising train pipe pressure may be difficult. It's probably therefore easier to treat it as though you don't have graduated release.

 

Is the dual pipe system only used on passenger stock? I was watching a container train passing through Basingstoke yesterday and noticed that the wagons only had a single pipe each (with red ends)

 

Interesting competency management issue there, a brake that is rarely used will be hard to remain familiar with, and it will be difficult to teach as well unless one hires a compatible rake of carriages!

 

That is largely correct. The earlier airbraked freight vehicles such as the FFA and FGA type freightliner wagons were dual piped as were HAA merry go round hoppers and rail tank cars built with or converted to air braked in the 1970's and early 1980's.

At a later date, most tank cars were converted to single pipe operation.

Cheers, Neil