Trains getting their TOPS classification changed.

[stadler]

Not previously mentioned is that GWRs 800/3s were originally ordered as all-electric 801/0s, and their carriage numbers remain as such.

Minor point but the 801s are bi mode rather than all electric. Both the current LNER ones and previously proposed GWR ones were always intended to be bi mode trains. The only difference is that the 801s have a much smaller fuel tank and much less powerful engine than the 800s and 802s have.

 

[Spartacus]

Minor point but the 801s are bi mode rather than all electric. Both the current LNER ones and previously proposed GWR ones were always intended to be bi mode trains. The only difference is that the 801s have a much smaller fuel tank and much less powerful engine than the 800s and 802s have.

They've one engine per set for emergency use only, I certainly wouldn't class them as bi-mode.

 

[Doomotron]

They've one engine per set for emergency use only, I certainly wouldn't class them as bi-mode.

I'd consider the diesel engine in an 801 the equivalent of the last mile engine in an 88. They couldn't really be used on their own.

 

[Helvellyn]

39x was originally for high speed stock (Pendolinos) so the javelins fit in (with the penchant for numbers ending in 0 or 5) 397 fits, sort of, as 197 is another CAF class.

Class 37x was originally for high speed units, hence the APT-P was Class 370, Eurostar Class 373 and then the latest Class 374 units.

the oddity was the Thameslink Class 371 proposal, followed by the Class 375 Electrostars (then classes 376-379).

Interesting about 455s and ‘510s’ - I had thought that 5xx class numbers were for non-Southern DC electric units.

Feels like BR was considering moving to use the 5xx series in order for all new third rail EMUs, just like the 3xx series was for ac overhead units, rather than continue the Southern practice of using a whole set of ten numbers for a "family" of units.

Can only presume they skipped Class 509 because Class 510 was then similar the Class 210 DEMUs (which in turn saw classes 208 and 209 skipped when they were introduced).

 

[Glaswegian]

Maybe not entirely what the OP was thinking of, but the first gen DMUs initially had multiple class numbers for power and trailer cars which eventually reverted to a single class per type. So, for example, for class 101 the DTCL were class 144 or 147, the TSL class 162, the TBSL class 168 and the TCL class 171, all eventually reclassified back to class 101.

How would this have interacted with the numbering of units? In particular, how would it have interacted with the SR practice of using only the last digit of the class number in the numbers of the units?

 

[norbitonflyer]

How would this have interacted with the numbering of units? In particular, how would it have interacted with the SR practice of using only the last digit of the class number in the numbers of the units?

Who knows. DMUs did not get official set numbers until many years later, other than on the WR, which only used three digit numbers with a depot prefix eg L301 for a Laira-based 3-car set

Weren't some more 'obvious' class omissions done because at least some of the relevant numbers were taken up with rolling stock, which once withdrawn meant it was later possible to 'backfill' them.

Notably the omission of classss 61-65, as there were still many mark 1 emus with power cars in the 6xxxx range.

The 50xxx and 56xxx DMU vehicles were renumbered into 51xxx and 59xxx to avoid TOPS clash with the class 50 and class 56.

No - both those ranges were already in use by DMU vehicles - (power cars 50000-52105, driving trailers 56xxx, trailers 59xxx) - the renumbering was into the 53xxx and 54xxx ranges respectively.

The Deltics had already gone, so the 55xxx single-unit DMUs did not need renumbering.

A handful of 59xxx trailers and 600xx Hastings unit vehicles were renumbered to make way for new locomotives.

 

[wickham]

Personally i would not count that. That was a completely different train. I believe that was a Networker design. It was intended for Crossrail but it was never designed by Bombardier and was a completely different train. There was eight of these proposed Networker trains (171 331 332 341 342 371 381 471) but none got built.

I beleive Class 171 was for Waterloo-Exeter replacement units and 471 for Waterloo-Bournemouth units: As mentioned here it seems at 341 was for Crossrail (or LIverpool St-Shenfield ?), but what were the others intended to be (331, 332, 341, 342 and 381), presumably all intended Network Southeast units?

 

[Sun Chariot]

No - both those ranges were already in use by DMU vehicles - (power cars 50000-52105, trailers 59xxx) - the renumbering was into the 53xxx and 54xxx ranges rerespectively.

Thanks - my memory was back to front and I was thinking that it was 53xxx and 54xxx ranges which already existed and stayed as is.

 

[43096]

Who knows. DMUs did not get official set numbers until many years later, other than on the WR, which only used three digit numbers with a depot prefix eg L301 for a Laira-based 3-car set

Almost.

L prefix was for Old Oak/Reading ("London")
P prefix was for Laira ("Plymouth")

 

[Sun Chariot]

Almost.

L prefix was for Old Oak/Reading ("London")
P prefix was for Laira ("Plymouth")

And also...
B (Bristol)
BX (Buxton)
CA (Cambridge, I think had sone 101s thus marked; my photos are boxed up)
C (Cardiff)
CH (Chester)
LO (Longsight)
NH (Neville Hill I think - I saw cl 110 NH669 with the prefix)
S (Swansea)
T(ylesley)

The excellent website www.railcar.co.uk has literally thousands of DMU images. Many enjoyable hours perusing their photos - especially the classes I didn't get many / any photos of.

 

[TheHovisKid]

The 50xxx and 56xxx DMU vehicles were renumbered into 51xxx and 59xxx to avoid TOPS clash with the class 50 and class 56.

Into 53xxx and 54xxx.....

A few 5910x were renumbered to clear the ARC 59s

 

[Spartacus]

I'd consider the diesel engine in an 801 the equivalent of the last mile engine in an 88. They couldn't really be used on their own.

They're not authorised for last mile type usage though, only in emergencies; I'm not sure one engine can power all systems and move the train at a sensible speed.

 

[Sun Chariot]

Into 53xxx and 54xxx.....

A few 5910x were renumbered to clear the ARC 59s

Thanks, yes, answered on post #36

 

[Doomotron]

They're not authorised for last mile type usage though, only in emergencies; I'm not sure one engine can power all systems and move the train at a sensible speed.

They can get up to about 60 on diesel (quite slowly) and they do so in service, but only when connected to an 800. They probably have done it on their own in exceptional circumstances, though.

My reasoning for calling them last mile engines is that the one engine is not really useful for regular diesel work, but is there if needed.