Vivarail's 'D Train' - 'D' stock reborn

To get around the Telegraph Paywall, it is possible to read a cached version here.

As miff says, a very moving obituary.

That really does put the withdrawal into context!

So near - so far.

The interiors of these recycled trains were really attractive and when they actually ran seemed well liked by passengers.

However from the outset the idea of converting a generally reliable LUL electric multiple unit to run on diesel power was risky. This was even more risky when they chose to shoe horn in road vehicle engines, generators, radiators and control gubbins all into very cramped rafts hung below the vehicle where there was often not sufficient air flow across the radiators.

Sadly towards the end of VivaRail, the right answer for Marston Vale was almost there. Dump the diesels, fuel tanks etc and fill those rafts with batteries making it a battery electric Class 230. The traction motors won't care where the power comes from and coupled with a fast charging system at each end of Bedford-Bletchley the line could have been among the first to enjoy emission free services without incurring the expense of knitting.

They were actually trialling the fast charging system at Bletchley. The 40 mile range they demonstrated by the class 230 battery demonstrator was more than adequate for a 32 mile round trip to Bedford without intermediate charging. Moving to battery power would however mean the trains would not suffer the infuriating reliability issues witnessed during the summer time whith overheating issues linked to the radiators getting clogged. It is also sad to think that the proposed Greenford battery trial using the demonstrator unit has also presumably been abandoned too. So near...

I believe that the TfW version resume driver training next week (or was it month?!). So they will still live on. Must admit when there were reports of a "Thermal Incident" outside Wrexham the other day, I did wonder! Turns out it was just 175008 having a trip down memory lane and BBQ itself (again!)

Battery performance degradation is a real but very complex thing that depends on multiple things, the most significant being the battery chemistry and how it is treated (the best way depends on the chemistry). The effects differ depending on the different chemistries, but my understanding is that the performance of the batteries that would be used has almost no reduction in capacity until it relatively suddenly falls off a cliff, at which point it would be replaced.

So when will it start? Where will the 230 get repaired?

I don't suppose we ever know the true facts down to this level of detail but it would be interesting to understand cause and effect here i.e. was engine unreliability a result of poor design or poor selection, then was inability to sort it out a contributor to collapse of the company, or a symptom of it if the company was already so low on resources as to be unable to sort it out.

And I do mean true facts. Anyone can sit at a keyboard and speculate or print canteen gossip or "my friends mate in the know says" stuff.

I doubt we will ever know the true sequence of events; apart from anything else too much will be bound up in confidentiality agreements even post bankruptcy as the other parties will hold to them.

All ways, you can understand why the Train Operating Company dropped it as soon as they could on simple reliability grounds. It almost gave them the ideal reason to drop it.

These ideas are all very nice - but look too at the (digression) of GW 769s (ex 319s) those too have been dropped and going off lease all 19 of them without ever turning a wheel in revenue service. One can argue all one likes about DfT instructing cuts and post covid impact, but the fact is all the testing never yet got GW 769s t work reliability, and the axe fell on them because of this.

Long ago there was a famous learned society technical paper by the BR SR CM&EE *** who was in charge at the time the 71s were converted into 74s _ which was another reliability disaster _ and a key point he was made was, in simple terms, if you want to rebuild something into something else, don't.


*** WJA Sykes ?

That is hard to say - because there are five units and almost the whole time they have been there the service has seldom used more than one unit a day.

OK someone will be along to point out that on days x y and z there were 2 out, but the general case has been 1 unit.

So on publicly visible trainspotter data can't tell it all 5 actually are in full working order and capable of work, or they can only manage one at a time.

Equally professional data like Roger Ford's Modern Railways golden spanner data things are distorted exactly because the fleet is more generously provided for - on the mainland a fleet of 10 units would have 9 diagrams, and 20 units 19 diagrams, and so on. Since they have at least 3 if not 4 not in traffic, there is plenty of time for TLC.

On top of that ongoing infrastructure work means reduced mileage; the current Pier work for example. OK it;s only half a mile per trip less, but nonetheless adds up over weeks.

On the whole I suggest 484s must work on the "no news is good news" basis - if they were a shambles there would be smoke signals across the Solent bringing news.

Thus far the 484s seem to be reasonably reliable. Admittedly that should be fairly easy with ample back up units on the island. Yes the line was closed for several hours when a tree blocked the line in January - but that is hardly an issue with the 484s.

However there was a recent (also January) issue with the wrong kind of ice - which saw all trains suspended...

www.islandecho.co.uk/trains-between-ryde-and-shanklin-suspended-due-to-icy-conditions/

Amusing to see some responses suggesting the return of the 38 stock - which also struggled with poor rail adhesion issues.

The big challenge for Island Line is to negotiate with the staff to agree practical changes to significantly reduce platform dwell time (basically speed up the door release and closure process) which is a flaw with the 484.

Until the line offers reliable turn up and go services, or at least clockface services, which give time to link to ferry and hovercraft connections, sadly I don't see any prospect of significant traffic growth, as most people will choose taxis, private cars or the island bus network.

A stock OPO conversion worked well. The 59/62 stock was just replaced.

None of your examples are as drastic.

Repowering / retractioning an EMU to make an EMU (three times) ? Converting passenger stock to departmental ? Done routinely.

74s / 230s / 769s all involved changing the underlying traction type - from straight electric to assorted forms of diesel + electric. Not done regularly. Or to my knowledge, successfully.

Sykes was the same engineer at SR CM&EE who got Rep and TC out of LH stock, converted 33s to push pull, and so on, and must have been around for the pre-27 stock for IOW. That level of modification worked.

In all my experience, though, large modifications always end up taking longer and costing more than expected even when an allowance has been made for this truism.

Ditto the standard and 1938 tube stock trains which went to the IOW - very successful

I wonder how the battery trial on the Greenford branch will fare

Looks like there is still some life left in this project.