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What was the purpose of the A1s?

Posted: Thu Jul 19, 2018 11:35 am
by Pyewipe Junction
This might sound like a stupid question, but with the 50 A1s, the LNER had (by my calculation) 399 'big engines'.

Were the A1s to replace the A3s, many of which had recently been rebuilt?

What about the proposal to build 25 express passenger diesels?

Re: What was the purpose of the A1s?

Posted: Wed Aug 01, 2018 10:23 pm
by pete2hogs
What's wrong with big engines? Better than putzing about with fowler 0-6-0's (still being built in 1940, IIRC)

Re: What was the purpose of the A1s?

Posted: Thu Aug 02, 2018 11:37 am
by Hatfield Shed
One would hope that all locomotive orders were authorised by the locomotive committee on the basis of providing adequate traction for the traffic departments projected operations.

In the case of express traction, new pacifics were required to replace the last surviving obsolescent atlantics which had their lifespan extended by the exigencies of war, and were then being steadily withdrawn and scrapped. (I don't have the references by me but my recollection is that the build and introduction into service of the final LNER pacific designs is mirrored almost 1:1 by withdrawals of the various atlantics still in service, with an average nine month 'lag' or offset between new pacific enters traffic, old atlantic withdrawn.)

As for diesels instead, these were experimental in UK terms. The BR establishment had the very similar LMS design available, and elected (wisely) to test that, and prove that it was inadequate in concept. It took another dozen years of development before adequate production designs of diesel traction units emerged, able to deliver in service what the pacifics were already proven to achieve.

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 2:14 am
by Pyewipe Junction
The more I think about it, the more I am convinced that the LNER diesel proposal wasn't serious - more like a case of 'kite flying' hoping to influence the incoming Railway Executive.

Were there really 50 Atlantics in service in 1946-8? (I assume this figure includes both ex-GN and ex-NE types.) And were they being used regularly on top-flight express services? I am not doubting the figures quoted, but I find the numbers surprising.

Another factor that must be considered (and don't forget we are talking about what might have happened, not what did happen) is the likelihood of the LNER introducing one, possibly two, classes of 4-8-2s for heavy passenger duties.

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 8:45 am
by jwealleans
The GC Atlantics made it past the war in the main as well, didn't they?

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 11:14 am
by Hatfield Shed
There were 53 LNER group atlantics that passed into BR hands from classes C1, C4, C6, C7. I suspect most of them only got an outing on a fast service when nothing in the way of a pacific, V2, B1, B16, B17 or K3 could be found. At least one commentator of the time observed that the Peppercorn pacific build resulted in better availability of the V2s for the fast freight turns.

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 3:13 pm
by 2512silverfox
I commuted on a fairly regular basis between Kings + and Newcastle in the years between 1946 and 1950. More often than not on the Tees Tyne with my father who travelled the route weekly. My spotting records do not show more than a handful of Atlantic sightings, and my memory, questionable after all those years, does not recall seeing any Atlantics other than station pilots and those parked at the edges of sheds out of use.

Indeed, the 4-4-0s were still to be seen, en passant, in parlous state and seemingly looking for jobs.

The new Pacifics were beginning to appear, to the excitement of the spotters, but all main line ECJS trains appeared to be Pacific (and sometimes V2) hauled. Even A3s and original A1s did not figure so frequently, some being transferred to the GC Area, and others further North.

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 6:26 pm
by 52D
Silver Fox i cant remember the sheds but Tweedmouth was one and maybe Darlington another that had Atlantics as standby locos for the non-stops so that could account for some of your sightings, I dont know if they lasted on this duty post war, im sure the last NER Atlantics were gone by 1948-50.

Re: What was the purpose of the A1s?

Posted: Fri Aug 03, 2018 7:00 pm
by john coffin
The last GNR Atlantic was 62822 a Grantham engine which was sent toward the knackers yard in November 1950.
There were 17 survivors into Nationalisation, but only 3 got BR paintwork and numbers.

As for the Pacifics, what has to be remembered is that we had just fought the war, and much production effort was put into
exporting goods, not importing them. The pre war Diesels were not particularly successful, and post war Diesel development
for such engines was not particularly advanced. The cost comparisons for importing American Diesels compared with obtaining
the A1/A2 Pacifics of both Thompson and Peppercorn I seem to remember worked out at about 10 steam engines to one diesel,
but more importantly, we would have had to import the diesel oil, whilst the coal was still "freely" available and relatively cheap.

Remember that even the Deltics were a strange compromise and extraordinarily complicated to service at the beggining,
whilst even now the new stuff being produced is compromised by the lack of national electrification.

Paul

Re: What was the purpose of the A1s?

Posted: Thu Feb 04, 2021 5:26 am
by rockinjohn
Hi along with the N2's(locals)/A3& A4(replete with garlic tablets on the main bearings),the most familiar,reliable day in day out members on Express turns out of the"X"to Leeds/York/Newcastle etc in steam days had to be the A1's, the same class members must have accured many miles above and beyond, especially the timken fitted members, oh for that past era boredom now.....

Re: What was the purpose of the A1s?

Posted: Sun Jul 23, 2023 5:37 pm
by MikeWild
I would like to slightly amend this topic by re-phrasing the question as 'What was the point of building the A1s?' or to put it another way 'What could an A1 do that an A2 could not?' or to put it yet another way 'Why did the LNER build a class of locomotives whose only significant difference to another class was a difference in wheel diameter of six inches plus consequential changes e.g. the frames ?' (I define the A2 here as those members of the class with Kylchap blast pipes and double chimneys.)
The LNER was a believer in horses for courses until Thompson took charge but even he wanted two classes of Pacifics.

Re: What was the purpose of the A1s?

Posted: Mon Jul 24, 2023 12:00 pm
by Hatfield Shed
I suggest this comes under the heading 'established custom and practise', and the 'inertia' that goes with it; supplemented by the confusion inherent to the nationalisation process. State of play:
1. The largest diameter wheel possible for a fast express locomotive, 6'8" was the limit of what was possible.
2. A smaller wheel for a mixed traffic design, which by that time had proven effective for the work up to 6'2".

Mr Bulleid had clearly noticed this convergence, and as a man not bound by custom and practise had already acted on it. Possibly no one left after his departure with enough clout to be heard, and prepared to break ranks for fear of any potential displeasure that might affect future career prospects, what with uncertainty all about?

In retrospect 'The A2 can fulfill the requirement and save us several tons of steel on every loco erected, compared to the A1 design.' seems very obvious.

Re: What was the purpose of the A1s?

Posted: Fri Aug 11, 2023 10:12 pm
by Eightpot
Can it be fairly said that it was Gresley that introduced the concept of the fast mixed traffic locomotive with 6' - 2" driving wheels in the shape of the V2 class?