Why 'A3'?

The LNER was never shy about classifying modified classes with a suffix (eg. D49, D49/1, D49/2, D49/3).

Why then did the modified Gresley A1s get a whole new classification to become class A3?
Why were they not instead known as class A1/1? (I'm not talking about 4470 which did eventually become an A1/1 in 1945).

When Thompson created his fleet of A2s the Raven A2s had all been withdrawn. And yet 'A2' was left vacant and we ended up with A2/1, A2/2 and A2/3s before the A2 slot was finally used in 1947.

Was there a reason, or did things just happen that way?

 

Hmm, good point - I'd never thought of that before! The only reason I can think of is that the whole class were being converted, rather than a few examples as in the case of the D49s etc. But then that doesn't explain the slightly odd way the A2s were classified.

 

Put simply: development order. Gresley A1 shortly followed by Raven A2. The update of the A1 developed by Gresley was considered to be enough of a change to warrant becoming A3 and of course, A4 shortly afterwards.

It's an interesting question. I think the LNER only started using the /1s and /2s after the A3s had first appeared on the scene.

Actually Thompson used "A2" for each new development of his 6ft 2in Pacific in turn except for the A2/1 class. The P2 rebuilds were originally class A - and then like the B1 which was intended to be class B - became A2. These became A2/2 when the A2/1 was developed. The A2/3 was originally the standard class A2, the /3 being added when Peppercorn's design superseded them. In railway history terms, LNER historians have been a little guilty of only referring to the final classifications and not making it more clear that there were changes made to the classifications.

 

Presumably because with the higher boiler pressure the A3s were considered as a "new" class rather than a variation of the original A1 class. The A2s on the other hand retained the same boiler but had detail variations such as shorter wheelbase, double chimney, multiple valve regulator etc within the same basic specification.

Remember also that when the original A3s were introduced the Raven A2s were still in use with the first example withdrawn in 1936 hence A3 was the next available classification - followed by the A4s as the improved A3s with the addition of streamlining.

That gives rise to a further question in that given the A5 classification given to Robinson's GCR Class 9N 4-6-2T what classification would have been given to any future Gresley / LNER Pacific design and why did the "tank" series of Pacific designs start at A5 ?

 

When the LNER set up their classification system in 1923 some letters with both tender and tank classes had a gap to allow for new tender classes in future. However the size of the gap was presumably a bit of a guess as to what might be needed, whereas developments didn't work out like that. The extreme example is that whereas there was only space for two new Pacific tender classes alongside the two existing ones, there was room for 12 new 0-6-0 tender classes, of which 4 ended up being used (J38-J41).

Gresley seems to have been happy to skip around the tank classes on running out of space - so another Gresley Pacific after the A4 would probably have been A9.

 

Similar thing happened with the Great Eastern 4-4-0s. Some were progressively rebuilt (with new different design boilers) to go from D14 through D15 to D16.

Also V1 2-6-2 tanks with 180 psi boilers being either built new or converted to V3 with 200 psi ones.

 

They were using class part numbers very early on for some classes, but it wasn't that common. Example classes I've just picked randomly from the green books: D32 (split into D32/1 and D32/2 in 1924); D30 (also split 1924); or B5 (1925). Some had different diagrams which didn't receive official part numbers until slightly later, such as class B4 (1927).

 

So what was an A10? I've recently seen that designation used in relation to Flying Scotsman.

 

I think the A10 referred to A1's not yet converted to A3 when Peppercorn's A1's were introduced.

 

Was it not ET who introduced the A10 classification to make way for his rebuild of 4470?

 

That is correct - under Thompson, the remaining Gresley A1s became class A10 and the new A1 was Great Northern (which we know as A1/1 - which is what it became when Peppercorn took over).

 

Based upon historical precedent, what would be the correct LNER class notation for the new P2, 2007 Prince of Wales, given the significant number of enhancements that will be incorporated ?
Given the amount of changes the originals had in their lifetimes it could get a bit complicated

 

IIRC the LNER got as far as P2/3 so if that is correct, 2007 would be a P2/4 but does it really matter?

 

In the modern age, might that be changed to P2r4 or P2.4?

 

P2.4

 

If tradition is followed, shouldn't 2007 be a P2 and all the rest reclassified?

Dave

 

Well if you want to follow *that* tradition you could just as well call it P1!

 

Good point.