A Q1 for you, just in case you hadn't seen one before......

One was saved as part of the National Collection, and is seen here at the Bluebell Railway back in 1980. I think it's at York now.

A little help for next time:

It's pronounced "GLOSS-ter," not "Glohw-ses-tehr":

https://www.oxfordlearnersdictionaries. ... gloucester

Well, when it comes to excuses, just think about the Southern Pacific GS class, which the SP declared as "general service" instead of "Golden State".

And in fact, while the Merchant Navy construction officially was permitted, the serial building was delayed due to material shortage. So I don't see any stupidity but rather a sort of wisdom, as the wartime need for steel set the priorities right and equalled out any wishful thinking.

By the way, as the fast passenger trains between London and the Channel ports were suspended due to wartime, the Merchant Navies were used as - guess what - mixed traffic engines!

Mike

I'm going to take a slight detour to comment on the weakness of European couplings. Yes, drawbar capacity is very limited, but the major advantage, at least for a passenger train is the lack of slack in the train when the cars are cranked down tight to the buffers. The train moves as one unit. Running the Wolsztyn Experience passenger trains over 10 years ago, the contrast in the way engineers brake that train versus a U. S. train is night and day. A U. S. engineer wouldn't dream of stopping an American passenger train with just the locomotive brake, but that is the standard way of stopping the 2 or 3 car trains in Poland. And they do it by coasting, applying a little brake, coasting, applying a little brake (and I mean like a half-a-second shot of air), and pretty much coasting to a stop. The general pattern for operating the Wolsztyn-Posnan train, with 17 intermediate stops in 52 miles, was get up to speed (50-55 mph), stay there for 3 or 4 minutes, then start coasting for the next station stop, eventually using short burst of air to slow the train down, preferably finishing by coasting to a stop in the next station. Nothing at all like dragging a U. S. passenger train down from 25-30 mph under power coming into a station to a stop in a train length, which is how Amtrak does it in the corridor.

I was doing some quick research, and while I didn't find any sources that directly answer your question - I came across a few that might be helpful to you all the same.

This book has a chapter on WWII oversight on Britain's railways. Hopefully the discussion of agencies and citations might help to identify specific sources in the UK National Archives: https://www.icevirtuallibrary.com/doi/abs/10.1680/vor.33436.0005

Historians have done quite a bit of research into the management of Britain's wartime economy, and think there is a good chance that you will be able to find some sources and active researchers that can offer some insights on your question.

Here are a few contemporary papers that might be helpful:

Experiences with British Railways Standard Locomotives (1954)
https://journals.sagepub.com/doi/abs/10.1243/JILE_PROC_1954_044_028_02?journalCode=jila

Some Notes on the “Merchant Navy” Class Locomotives of the Southern Railway (1946)
https://journals.sagepub.com/doi/abs/10.1243/PIME_PROC_1946_154_040_02

Here are a few books that seemed to have interesting material on the development of the class. Searching 21C1 in Google Books can reveal some snippets.

British Locomotives from the Footplate
Oswald Stevens Nock, 1950

Locomotive Practice and Performance in the Twentieth Century
Cecil John Allen, 1949

But that is what I kind of love about the Q1... its just so... wrong in all the right ways. Its hard to believe it ran on the same island as the stuff Stanier and Gresley made, let alone the very unified look of anything the Great Western did. From what I gather, the British age of steam was very concerned about aesthetics, doing things that seem strange to almost all foreign steam builders such as the inside frame cylinders for example, all in the name of preserving that aesthetic (for example like how a Great Western Panier tank due to its inside frame cylinders and valve gear had to stop at very specific wheel locations to allow the driver to grease the rods, and any other position would make it impossible to access them to properly grease them).

... and other than the Q1's inside frame cylinders, there is almost nothing else on that engine attempting to be aesthetically pleasing. Its such an eyesore... and it ran on the same network as H.K. Porter and Vulcan USA built 0-6-0T's, and ex-LBSCR Terriers and E2's. If the LMS, Great Western and LNER were trying to be modern and uniform the Southern has a strange eclectic nature to it that is really neat.

.

The problem here is, it wasn't the British "minders" that were "stupid" in approving these locos for mixed-traffic application.

No, this was a misunderstanding by the OP of British rail freight traffic, and the appropriate application of steam propulsion to it accordingly. And I'm not calling him "stupid," just under-educated in this regard.

Here is a paper by Mr. Bulleid that discusses design considerations that influenced the design of the Q1.

Locomotives I Have Known
O. V. S. Bulleid, June 1, 1945

I was able to find a copy of this paper on-line:

https://web.archive.org/web/20200812162036/http://users.fini.net/~bersano/english-anglais/english-anglais/OVS%20Bulleid/Locomotives%20I%20have%20known.pdf

One somewhat minor point on the Merchant Navy class design was that their shape and dimensions were engineered to permit the locomotive to be cleaned using a car washer rack, reducing the man hours needed to wash each locomotive.

Here is a brochure from the naming ceremony of the "Merchant Navy" class locomotive "General Steam Navigation" at Waterloo Station, February 20, 1945 that has some additional information.

https://collection.sciencemuseumgroup.org.uk/objects/co8060176/southern-mixed-traffic-locomotives-merchant-navy-class-naming-ceremony-of-general-steam-navigation-leaflet

I hadn't heard about the design being related to the use of wash racks. Were there wash racks in use at this time? I would think they would be problematic with open-window, wood-bodied rolling stock?

Just because it's a mail train doesn't make it light.

I'd imagine most US mail trains were much heavier than a passenger train.

I've seen photos of US mail/express trains being pulled by double headed 4-8-4s/4-8-2s, probably in the 20+ car range. Not something a 4-6-2 could handle.

The "light 4-8-4s" of a modern design were probably about as close to "general purpose" as a late post war steam design could be. thinking of engines with roller bearings/ type e super heat etc like NCSTL 576, NdeM 4-8-4s.

N&W J 4-8-4s with their smaller drivers would also have been mostly interchangeable with many freight types such as a 2-8-4s, or mikados used on time freights.

After N&W rented diesels pending their own passenger GP-9's they tried the J's in freight service. They were not good at it because of the suspensions being tightened to achieve 100 mph on 70 inch drivers. N&W also had an outstanding and more powerful fast freight locomotive in the Class A 2-6-6-4 which also has 70 inch drivers.

Remarkably, at the time Reading Company was bullding fast freight 4-8-4's with the T-1 class having 70 inch drivers and 27x32 cylinders, same as a J, and they did well with 5000 ton Alphabet Route trains, keeping ahead of passenger trains between 4-track sections of railroad. Best I timed a T-1 was 75 mph, which was track speed on the NY Branch, pulling a 16-car Ramble. Timing was my Hamilton watch with numbered catenary poles as mileposts so it wasn't "sandhouse talk."

Phil Mulligan

This is interesting because I have always presumed the fastest parts of the New York Branch were north/east of where the electrification ended around West Trenton. What were the peak speeds experienced further toward E-port/Jersey City, and how far did that Ramble go?

A lot of British railroad practices and projects never made much sense to me.
But as for the production of these engines, what was stupid about it in your mindset? Was it a bad design, or just a supposed waste of materials in wartime?
I don't profess to know much about these engines in any context.
I've heard this before.
I, too, have had to explain the vastness of North America to Europeans before. When I was in Huntsville at the Space and Rocket Center one time, I encountered a German group, many of whom spoke no English (which runs in the face of all I've been told over the years that all of them must take English in school). Anyway, with my ancient college German, I talked with a couple of them and found they wanted to just zip over to New York City for a day by car (and then maybe swing through Washington DC on the return). They were quite surprised when I explained how far that was from North Alabama.
The first time I crossed the pond in 1988, I was utterly shocked how small the European countries really were when you were on the ground.