The newly formed Southern Railway inherited locos from across the Southeast, and due to their age, quite a few of the more dated 4-4-0s needed replacing. Richard Maunsell, who had been the last Chief Mechanical Engineer of the SE&CR, continued his position upon the grouping of the railways in 1923. He led the Southern Railway into a new era of design.
Building on his tried and tested ideas, Maunsell borrowed new ideas from designers and previous colleagues at other railways. As a designer, he was
known for his skills in engineering management, hiring teams to create economical designs. The U class is the perfect example of this type of practical
composition and design evolution.
The initial batch of U Class locos was created due to a combination of the operational requirements for a semi-fast and cross-country capable loco, and
as an immediate reaction by the Southern Railway to the fatal Sevenoaks Railway accident. The accident involved a SE&CR K Class ‘River’ 2-6-4 tank
engine. These engines were known for rocking so it was decided that the entire class would be rebuilt as 2-6-0 tender locos.
Taking inspiration from his previous 2-6-0 design, the N Class, Maunsell and his team developed the first ‘River Rebuilds’. They also used new developments used on other Mogul locos, such as the GWR 43xx.
Twenty locos were converted throughout 1928, and these were redesignated as the U Class; but sadly, the ‘Rivers’ lost their named identities in the process.
The U Class did receive a rather memorable nickname as an alternative. Built during the interwar period, this quintessentially Southern loco was dubbed the
U-Boat, which is probably due to surprise encounters with German submarines of the First World War being fresh in the memory of those who lived adjacent
to the English Channel.
Prior to the accident, an order had been placed for further K Class locos, but instead of pursuing this unsuccessful design, the order was amended to be 20
brand-new U Classes instead. The construction was shared between Brighton and Ashford works. As construction was drawing to an end, an order for a
further ten locos was placed; this order was completed in early 1931 by Ashford works.
A total of 50 locos were classified as the U Class. However, the rebuilds and new builds looked distinctly different. With a higher running board on the newly
built examples, they sported a much smaller wheel splasher. The cabs were also different, as the rebuilt locos retained the 4 look-out windows of the K
Class, whereas the new builds had 2 large ones.
Maunsell used a straight-sided, smaller 3,500 gallon tender on the Earlier rebuilt versions of the U. Later, newly built locos featured a larger 4,000 gallon
version; these had inward-sloping raves to prevent coal spillage. Although they were built without them, smoke deflectors were later added to the whole class by the Southern Railway in the mid-1930s.
Working across most of the South, the U-Classes were reallocated to a variety of sheds throughout their lives. Although Moguls were generally used for
freight duties, the U-boats were utilised as a mixed traffic loco; this was due to their reliability as an all-around performer.
Passing to British Railways, these busy locos continued dependably right through to 1966 when the last of the class was finally withdrawn. Four examples have since been preserved, and these consist of a mix of one rebuilt ‘River’ and three newly built locos.
Our highly detailed OO Gauge rendition of the SR U Class will represent the locomotives that were part of the newly built batches. It will be available in a variety of guises, covering its Southern Railway and British Railways liveries.
The range features a selection of detailing variants, including flush and riveted buffer beams, flat or rounded domes, flat-fronted cylinders or cylinders with
piston tail rods, snifting valves on Southern Liveried locos, and smoke deflectors on all models apart from the earliest representation. All models feature the 4000-gallon tenders. Two BR livery models will also feature AWS gear on the right hand side running board.
You can look forward to a smooth-running mechanism, factory-installed speakers, NEM coupler pockets, an ESU 21-pin decoder socket (DC models), fitted MoPower stay-alive capacitor, tender pickups, and firebox flicker with a dynamic fire draw effect (DCC/Sound fitted models).
We are pleased to say that the project is already at the tooling stage and engineering prototypes are expected in early 2026.
The order book is open, and you can pre-order your models directly from us today or from any of our Official Retailers.
Order your model now by clicking on the item below:
