Bulleid MN "Merchant Navy" Class 4-6-2

When in March 1938 the Board of the Southern Railway authorised construction of ten locomotives of a new mainline passenger design neither they, nor anyone who knew of CME Oliver Bulleid's work whilst assistant to Nigel Gresley on the GNR and LNER, could scarcely imagine the machine that eventually emerged from the works. After an eight coupled configuration had been turned down by the Civil Engineer a more conventional Pacific wheelbase was settled upon, but thereafter very little else was conventional about this engine. Bulleid was an imaginative and perhaps intuitive (rather than precise) designer leading to many changes of mind throughout the design and construction process. The boxy bodywork, described as "air-smoothed" rather than streamlined (being designed to go through carriage washing plants) and Bulleid-Firth-Brown (BFB) wheels were merely the cloaking for a host of innovative features - some untried and untested - and methods of construction introduced with the laudable aim of easing the workload for (and no doubt reduce the costs of) loco crew and maintenance staff. In fact some innovations introduced cause and effect to ripple through the design with one innovation introducing extra weight somewhere in the loco requiring another innovation elsewhere to reduce weight.
MN Poster This is a photograph of a Southern Railway poster featuring the new MN class portraying by its technology the railway company as being a modern progressive organisation.

photograph by Michael Taylor

Nº21C1 Channel Packet caused quite a sensation when first unveiled to the public on 18thFebruary 1941 with her unusual shape and, for Britain, number. In the early years of these locomotives they were frequently known by the nick-name "Channel Packets" rather than "Merchant Navies", after the first in the class. She is in matt malachite and has cast number plates, though that on the sloping front will soon be removed and replaced with a painted number on the vertical face immediately below.

photograph: Roy Vandersteen collection

Novel features included an all-time high boiler pressure of 280lb p.s.i., clasp brakes, welded steel firebox with thermic syphons, steam operated firedoors (novel in Britain), a steam driven electrical generator providing comprehensive headcode, inspection and cab lighting, a cab layout permitting the driver and fireman to work without getting in each other's way, but chief of all a totally enclosed motion encased in an oil bath situated between the frames. This motion itself included the new feature of a chain driven three throw crank shaft operating valve gears for each cylinder. In his motion gear Bulleid was strongly influenced by automobile design with its potential increased reliability and reduced maintenance compared to conventional locomotive motion design.
21C1 Nº21C3 Royal Mail engaged in changing engines at Salisbury on a Plymouth-bound train. The number can now be seen to be painted on the vertical face. The letter 'C' is also noticeably larger than the numerals.

photograph: Mike Morant collection

The "Southern" plate on the smokebox door was unpopular with loco crews as it resembled an upside-down horseshoe so was soon replaced with a "Southern Roundel" with the added section carrying the date of the manufacture. Despite a wooden mock-up being made immediately after nationalization, the roundel was not replaced with a similar one bearing the legend "British Railways". In the early days of BR the numbers, by now simply painted, carried the prefix 'S' in front of the Southern number, but when the locos were renumbered in the 350xx series, this was replaced by a cast LMS-style plate on the smokebox door, hidden in the photograph below by the train headboard.
Nº21C4 Cunard White Star at Waterloo with a special train for the maiden ordinary passenger carrying voyage of the "Queen Elizabeth", 16th October 1946. Note the "quartering" of the buffers and the letter 'C' which is now slightly smaller than the numerals!.

Whilst an Exmouth Junction engine, a low flying German aircraft shot at Nº21C4 on 30th November 1942 at Crannaford, near Whimple.

photograph courtesy Jerry Ricketts and stated to be in the Public Domain when posted on the newsgroup.
It will be removed if the original author deems that to be necessary.

It was originally intended to name this class after Allied victories. Nº21C1 had been lined up for the name The Plate but in 1941 there had been few victories to commemorate. Consideration was then given to naming them after Commonwealth capitals but the Chairman of the Union Castle Line then suggested naming them after shipping companies which had called at Southampton Docks in peacetime.
35027 Nº35027 Port Line at Victoria. She is in the experimental blue livery applied to all bar three of the Merchant Navy class locos. Note the difference in appearance when compared with Nº21C1 and Nº21C3 above. Many modifications to the "air-smoothed" casing were tried before this general arrangement was settled on, mainly in an effort to avoid smoke drifting down and obscuring the driver's view! She now has the "Vee" shaped cab that, with its angled front spectacle plates, increased vision and reduced glare.

Port Line is carrying the prestigious "Golden Arrow" regalia of headboard, arrows and British and French flags.

photograph: Roy Vandersteen collection

Nº35004 Cunard White Star enters Waterloo heading plum and spilt milk liveried stock.

photograph by Mike Morant

35014 Nº35015 Rotterdam Lloyd hauling the Bournemouth Belle. Location is thought to be near Surbiton. This headboard is of the Southern Railway design.

A few years earlier, on 20th June 1947, Nº21C15 had the distiction of hauling the inaugral "Devon Belle" from Waterloo to Wilton.

photograph: Mike Morant collection

Nº35006 Peninsular & Oriental S N Co on shed at Exmouth Junction sometime between December 1948 when she was renumbered and March 1951 when she was painted in BR blue. This loco, now restored at the Gloucestershire Warwickshire Railway, had a unique claim - she was the only one of her class to remain at one shed (Salisbury) for the whole of her SR/BR career. She also had the same tender attached throughout, though this was sold separately from the engine after being sent to Woodhams at Barry Island.

photograph: Mike Morant collection


All photographs are copyright

First | 2nd

Modified Locos | Data | Nameplates | Tenders | About those fires...

This page was last updated 18 May 2004

SR Target