For the benefit of those of us, like me, who are not familiar with present 315 allocations, were these TfL Rail or London Overground units?
(Equally, when the time comes, would it be possible to have an indication of which of the two operators they are being withdrawn from as well as the numbers please?)
London Overground only have units 801 - 817, the rest (818-861) are all TfL Rail sets. Another factor that should help clarify the difference at this stage is the lack of LO replacement units to enable their 315s to be withdrawn - only the TfL Rail/Crossrail units have been delivered for passenger use so far
"I don't make mistakes. I make prophecies which immediately turn out to be wrong." "And now, excuse me while I interrupt myself" - Murray Walker OBE
Student of Mechanical Engineering at the University of Nottingham (loosed upon the real world for a year)
I don't know why because I'm normally all about modern technologies but I'm actually sad to see them go, to be honest I'm actually surprised they haven't found use elsewhere.
I quite like 315s too, but don't forget Vivarail hasn't found many homes for D78 stock yet, so why buy another old fleet? And even if there was a good case in a year or two there are lots of BREL York EMU trains coming up for withdrawal soon, so there's quite a choice if one was needed.
Anybody know why these modern, sliding door units haven't been reserved by Vivarail as likely candidates for re-engineering?
(1) The units are NOT 'Modern' - they are around 40 years old and suffering from corrosion plus other age related problems.
(2) they have never been updated - unlike the D stock which received brand new bogies only a decade before withdrawal by TfL.
(2) They are 25KV units and consequently the traction gear cannot be fooled into thinking its working off 750V 3rd rail as per the 319flex units or the D stock via the installation of batteries / diesel engines.
Trains have had sliding doors for more than a century - indeed the old LNER-design class 306s, which were replaced by the 315s, had them. British Rail was unusual in sticking with slammers until the late 1970s - a legacy of the Southern Railway's conservative design policies. (Like Trigger's Broom or the Ship of Theseus (depending on your preferred cultural references), many 1960s-era SR units had originated as Edwardian-era steam-hauled stock, of which the underframes and bodies had been replaced at different times over the years - sometimes more than once - but still conformed to more or less the original layout.) The SR slam-door designs, rather than the more modern LMS and LNER designs, were the basis of most BR multiple unit designs until the late 1970s. (Even then, the PEP types could be seen as special cases - the 313s, 314s and 507s were destined for lines with long underground sections and, along with the 315s, were to replace or run alongside existing sliding door trains.
... a legacy of the Southern Railway's conservative design policies. (Like Trigger's Broom or the Ship of Theseus (depending on your preferred cultural references), many 1960s-era SR units had originated as Edwardian-era steam-hauled stock, of which the underframes and bodies had been replaced at different times over the years - ...
At least one book on the Southern Railway (S.R.) quotes from the minutes of meetings held by the Directors / Managers of the Southern Railway. It had been pointed out that these new modern stock were providing excellent service for the LMS and other railways and that the Southern should look into it.
The reply from the S.R. operating department was rather interesting,
1. Sliding door stock was alright for railways carrying relatively few passengers, but not the numbers carried by the S.R. 2. It was important to the S.R. that each passenger had a seat. (OK they still had standing into London Bridge even with the S.R. high capacity stock) 3. They had also noted that the time to unload sliding door stock was greater, and that it would have been impossible to run the peak timetable on the S.R. with the increased dwell times.
These intelligent points lived on into Southern region days.
Similar views were also made by the Metropolitan Railway!
Were the 312s the last EMU design to be built with slam doors?
Yes, they were built in two batches; The 1975 batch was for 19 x 312/1 for Liverpool Street - Clacton/Southend Vic services and 4 x 312/2 for London Midland to compliment their 310s out of Bletchley Depot. The later batch was 26 x 312/0 for the Kings Cross outer suburban lines which were still being delivered in 1978. They were the last of the Mk 2 derived EMUs and also the last of what are now referred to as "1st Generation" EMUs.
The production of 315s followed on from the 312s at BREL, York with the first few units arriving at Ilford late 79/early 80, though their design preceded them with the PEP experimental units then the Class 313 from 1975/6.
So the 315 is essentially a later build of an early 70's design. Modern it certainly is not and there will be much newer rolling stock heading for scrap soon.