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

Problem is, they're converting the units from DC to AC traction systems. This amounts to basically a complete retractioning - and AC systems, while they do have some notable advantages over the "classic" type of DC control used by the D78s in their life on LU, also bring in a lot of complexity.

Fair enough, but it still wasn't then too late to do a version retaining more of the original train equipment such as the camshaft controlled dc motors scheme. That would have been less of an upheaval maybe.
Anyway I hope they do get the new schemes working well.

And there's a "D Stock" on the pier...

There's a lot of railway history around Philadelphia; including what I believe to be the world's first locomotive boiler explosion.

Good luck to them, an interesting idea.

I do wonder if the D-stock can become a universal spot-hire/infil train to plug gaps in procurement, allow new routes to be tested without huge investment etc.

Maybe as well as the swap-out propulsion systems, they need to work on virtual gauging etc so they can drop in more easily

As for what happens when they run out of D stock vehicles - it is clear VivaRail already have flagged up some ideas including retrofitting existing DMU stock to operate either entirely on battery or battery diesel hybrids. Check out the comments at around 5:50 minutes in this video interview with the former Vivarail MD Adrian Shooter.

A key point of re-using the D78s was that the basic bodies and chassis were not yet life-expired. I'd imagine the 315s are pretty worn out by now.

The 315s are indeed pretty much life expired and would need work to make the accessible so I highly doubt they'll be seeing future use, the 317s similarly.
The only significant market for used deep level sock has been the Isle of Wight. Even discounting the diminutive loading gauge, by the time the 1972 stock are finished on LU they'll be going on 60 and are already needing work to stop them falling apart. Despite being 2 decades younger, the 1992 stock aren't in much better shape - build quality was lower and they've had a very hard life - add to that all the electronics being obsolete and their retirement will be to the scrapyard. 1973s were what the IoW were always said to be waiting for and they are in relatively good nick as I understand it, someone may take a look at the state of them when they do finally leave the Picc - but if they think there is a market for a train that small.

Reintroducing Pacers anywhere in the UK that isn't a heritage railway would be politically unacceptable so even if they weren't all worn out and of questionable crashworthiness it would be a fool who spent significant money on them - and Adrian Shooter is no fool.

My guess would be Networkers and Sprinters, but there are people who know far more about things like this than me

I like the concept of topping up batteries whilst the train is travelling as an alternative to extended dwell times charging batteries at the route terminus. Its so logical.

Overseas this concept has already been proven successful with buses, where its called in-motion charging (IMO) but here in the UK only the railways see the value of this concept.

I wonder if LU have ever thought of adopting this concept as a way of removing potential dangers of electrified rails from most stations.

The coming Picc trains will have battery power to reach the next station in event of power failure. Present trains do not. I wonder if this will lead to simplification of current rails around pointwork as a start.

Erm, I think you will find 'The IOW People' (as in the ones trying to run the service) were only too well aware of the need for new stock and how knackered the 38 stock was over the last decade.

If you are in the business of apportioning blame / or overlooking the problem then you need to direct your attention to the Whitehall district of London.

Unlike TfL, mainline TOCs are UNABLE to order any new trains unless specifically granted authorisation by the DfT in Whitehall. This is because new or extra trains will impact the amount of money the TOC has to pay to leasing companies and thus exposes HM Treasury / DfT into paying higher subsidies (you can be as sure as hell that private shareholders won't foot the bill for something imposed on the contract retrospectively). 

Thus new trains have usually only come in as part of refranchising / re tendering of contracts as this allows for HM Treasury to pick the cheapest bid while still getting new trains.

Unfortunately for the IOW it only returns a single MP to Parliament (and so was dismissed as 'not important' in political circles) plus the DfT have been desperately hoping they could come up with some sort of non railway solution to rid themselves of the system (and thereby avoid the problem of rolling stock replacement). therefore come franchise / contract renewal its been consistently overlooked by Whitehall mandarins while the SWT / SWR franchise doesn't have the authority to have intervened off their own bat anyway.

Hence we had to wait until the Ryde to Shankin line faced the very real prospect of suspending services for good through not having any trains before the politicians in Whitehall finally got off their backsides and did what the 'IOW people' had been shouting about for over a decade and sorted some newish rolling stock.

If the American model takes off, they don't need an infinite number of them, they hire out on a short/medium term to prove viability of a given route.

Down here in the southern wilderness, we have heard that the Boundary Commission have declared that the lsle of Wight parliamentary constituency should be split in two.

This means that the I.o.Wight railway could suddenly become interesting to the two political parties that could win these two new seats

Because of this, don't be surprised at promises of oodles of money being thrown at the remaining I.o.W. Line and the (remote) possibility of re-extending down to Ventor
(whether practical or not, it sounds good to local voters).

Whether D Stock could fit thought the Ventnor tunnel is debatable

However, because of the "two constituencies" proposal for the Island, don't discount ANYTHING being promised for the I.o.W. line