Alphanumeric Locomotive Classification

[AlanORourke]

Around 1900, HA Ivatt introduced an alphanumeric classification system on the English GNR. A capital letter indicated wheel arrangement; within each group loco classes were listed by number in descending order of tractive effort. Bazin used a similar system in the final years of the Great Southern & Western Railway in Ireland, and after 1925 the Great Southern Railways of Ireland adapted it to cover all the engines it had absorbed.

Just wondering if anyone knows exactly when Ivatt set up his system; or any other details of its origin.

Rgds Alan O’Rourke
Historical Model Railway Society Irish broad gauge steward

[Atlantic 3279]

Hello and Welcome Alan,

Without checking books etc, I cannot give an accurate date, but memory confirms that the scheme was introduced around 1900. I've never considered the question of what gave Ivatt the idea. Maybe others can help, if and when they have time?

Graeme King

[john coffin]

Hello Alan, I believe that you have not properly interpreted the way in which Ivatt introduced things, and it is made
more complex by the addition of various notes by Dr Tuplin who ascribed various classes with descriptions that none
of the older "experts" agreed with.

According to Groves, vol 3A, which was written with help from Kenneth Leech and others of GNR renown,
it suggests that in June 1900 Ivatt introduced a system which arranged classes by wheel layout, and then
in descending order, the wheel size which were further denoted by letters. Later in May 1906, a power classification
was also introduced. At which point the most powerful locos were at the front of the list with less powerful ones
further down the list. However, this broke down to some extent with the J21/22 which became 4 different classes
under LNER, ie, J1, J2, J5, J6.

At the beginning of the GNR, Sturrock Locos tended to be noted by the number of the first of each class, GA's tend to reflect
this fact. That seems to follow also, the locos of Cubitt and Bury.

According to Tuplin, Stirling locos were initially denoted by class number, then as modified, letters were added. However, these
do not always relate to details on drawings. So for instance it was always accepted that Stirling 0-4-2 were class F2, which suggests
that at some time a relevant Sturrock 0-4-2 might well have been called F1, however, no papers I have yet studied give details of that.

In 1922, when Gresley introduced the Pacific, the Stirling 8ft singles were basically extinct apart from No 1 still in storage at
Kings Cross, so that is why Nos 1470 and 1471, were designated A1.

Sadly like so many of these questions, there are more questions than answers, because at a time when the data was still available,
no one bothered to ask.

HTH
Paul

[Atlantic 3279]

Yes, I had always had the impression that the numeric part of the classification was at first arranged so that classes with largest driving wheels generally came first.
I believe the separate GNR system of power classification was also by a series of letters, the GNR J22 (later LNER J6) six-coupled goods engines for instance being "A engines" in the power classifications.

[john coffin]

Hello Graeme,
I am not so sure about the power classification since I think in the goods department it was much more
to do with the introduction of A and B class express goods trains, for which classes ( which later became) J1 and J2 were
introduced.

Whilst not explicitly stated in anything I have seen recently, I am sure that Gresley, since he was Ivatt's anointed successor.
would have been involved in the process. What is confusing is that class J1 was originally designated class E, whilst J5
were originally class B but uprated to class A, so what does that tell you about how coordinated the system was?
Since the J6 started out as class B also and was uprated to class A, and this happened around 1912, ie after Gresley became
CME, he must have been really involved in this re-classification.

The more we know the less seems clear.

Paul

[Hatfield Shed]

...Sadly like so many of these questions, there are more questions than answers, because at a time when the data was still available,
no one bothered to ask...

Nail, head, hit.
Someone in Gresley's team who saw the need for a method of systematic classification of the loco stock of the LNER. I would suspect that prominent and energetic mould breaking assistant to HNG; except for the fact that when he landed on the Southern, he made their loco stock classification 'system' yet worse...

[65447]

Having come from the GER, where all classes were denominated by the Letter Reference in the Order Book of the first order for a class, TW Worsdell introduced alphabetic classifications to the NER from 1886, although the alphabetic sequence of letters did relate to the wheel arrangement they were not applied in the same way that the late GNR/LNER developed. Other railways also used letter systems, but again not generally in the LNER alphabetic-to-wheel-arrangement. These introductions seem to have occurred across the world between c1900 and 1925, so there must have been some triggering event.
The TWW/NER system also used suffix numbers to denote variations to the types.

[Hatfield Shed]

... These introductions seem to have occurred across the world between c1900 and 1925, so there must have been some triggering event...

The military were very early into classification of standardised equipment, as their supplies moved from craft manufacture to factory production systems. As the railway companies expanded and 'the knowledge' began to exceed human memory I should think there was some knowledge transfer, and this was quite probably accelerated by the various conflicts of late C19th up to WWI.

[john coffin]

It is worth remembering that the wheel designation most commonly used was known as the Whyte system,
from America, and also that both many UK engineers for instance the Worsdells worked in the US for a time
in the 1800's and would have bought the information back to the UK when they returned.

the GNR sent a party out in Ivatt's time, and Gresley certainly was aware aware of things going on in the USA,
witness the relationship between the K4 Pacific's and Great Northern.

Paul

[65447]

It is worth remembering that the wheel designation most commonly used was known as the Whyte system,
from America, and also that both many UK engineers for instance the Worsdells worked in the US for a time
in the 1800's and would have bought the information back to the UK when they returned.

the GNR sent a party out in Ivatt's time, and Gresley certainly was aware aware of things going on in the USA,
witness the relationship between the K4 Pacific's and Great Northern.

Paul

Except the Whyte notation did not come into first use, in the USA, until after 1900...

[john coffin]

Given the way of the world, and the assumption that people tend to have these days that communication was slow
in the early years of railways, but it is worth remembering for instance that the B&O was working about the
same time as the Liverpool Manchester. and people from the USA came to visit the Rainhill trials.

As for Ivatt, he went to the USA from April to July 1899, so a reasonable man would assume that the Whyte
notation was being discussed in that period prior to its introduction at the beginning of the new century.

Worth noting that none of the preserved locos in pre grouping livery have the plates, but some in LNER
livery do.

Paul