Diagram of the Leader.

Leader was a revolutionary class of steam locomotive designed by Oliver Bulleid. It was originally commissioned by the Southern Railway but it was completed by British Railways in 1949. Image File history File links Bulleid_Leader. ... Image File history File links Bulleid_Leader. ... In physical chemistry, and in engineering, steam refers to vaporized water. ... A locomotive (from Latin loco motivus) is a railway vehicle that provides the motive power for a train, and has no payload capacity of its own; its sole purpose is to move the train along the tracks. ... Oliver Vaughan Snell Bulleid (19 September 1882 - 25 April 1970) was a British railway and mechanical engineer best known as the Chief Mechanical Engineer (CME) of the Southern Railway between 1937 and the 1948 nationalisation, developing many well-known locomotives. ... The Southern Railway in the United Kingdom was the smallest of the four railway systems created in the Grouping ordered by the Railways Act 1921. ... British Railways (BR), later rebranded as British Rail, ran the British railway system, from the nationalisation of the Big Four British railway companies in 1948 until its privatisation in stages between 1994 and 1997. ...

These locomotives had an unusual configuration with two power steam bogies, utilising sleeve valves and chain drive. The boiler and "tender" were placed on a common frame (thus it is often referred to as an 06-60 tank engine) with the boiler placed horizontally off centre by six inches, to create a corridor that linked the central fireman's compartment and the cabs at either end. The body was streamlined, the complete machine resembling a modern diesel locomotive, rather than a traditional steam engine. Chains were also used to operate the valve gear. Bogies This game was started by BBCs Dick and Dom as part of their hit childrens TV show, Dick and Dom in da Bungalow. ... Roller chain and sprocket Mack AC delivery truck at the Petersen Automotive Museum with chain drive visible Chain drive was a popular power transmission system from the earliest days of the automobile. ... A boiler is a closed vessel in which water or other fluid is heated under pressure. ... Tender may mean: one of several types of boat or ship, all sharing the general function of servicing another type of air or sea vessel: seaplane tender - supplies and services seaplanes submarine tender - resupplies submarines motor torpedo boat tender - resupplies motor torpedo boats ships tender - used to transport people... A tank engine (occasionally tank locomotive, especially in England, notably used in reference to Thomas the Tank Engine) is a steam locomotive that carries its own fuel and water on it, instead of pulling it behind it in a tender. ... In fluid dynamics, a streamline is the path that an imaginary massless particle would make if it followed the flow of a fluid in which it was embedded. ... Great Western Railway No. ... The Walschaert valve gear on a steam locomotive (a PRR E6s). ...

History

Five locomotives were to be built, but 36001 was the only one steamed, the others only reaching various stages of completion. 36001 was soon found to be a poor steamer. The welded boiler, with thermic syphons through the firebox, was designed using the experience gained in Bulleid’s highly successful Merchant Navy Class. However, the firebox itself, originally built without a brick arch, plus the special arrangements needed to allow for smokebox cleaning, made for poor blast. The sleeve valves, chosen because of the restricted space in the powered bogies, also gave trouble. The compartment for the fireman was excessively hot and cramped, to the point where firemen had to be called to volunteer to work on it, as opposed to being allocated. Their lot was not improved when a brick arch was eventually incorporated, as there was then a tendency for flames to enter the cab! The height of the tank filler cap was above the standard water tower height and the off-set boiler needed two and a half tonnes of lead alongside to level the engine, resulting in a great increase in axle load (resulting in the track being pushed out of gauge). In addition, the reversing gear often jammed. The drive and valve chains both stretched over time, making valve-timing unpredicable. Rebuilt 35024 East Asiatic Company at Exeter St Davids, 1962 with Atlantic Coast Express headboard. ... It has been suggested that Gauge (engineering) be merged into this article or section. ...

36001 was tested around Bristol and Eastleigh, using the LNER Dynamometer car as used by LNER 4468 Mallard on its record-breaking run. Ironically, once the engine began to show signs of improving, British Railways gave up on the project and the locomotives were scrapped. Today, all that is left of 36001 is one numberplate in the National Railway Museum. It has been suggested that this article or section be merged with Greater Bristol. ... Location within the British Isles Arms of Eastleigh Borough Council Eastleigh is a railway town in Hampshire, UK; and the main town in the Eastleigh borough. ... The London and North Eastern Railway or LNER was the second-largest of the Big Four railway companies created by the Railways Act 1921 in Britain. ... The Southern Pacific Railroads dynamometer car #137, July 1937. ... Mallard at York Number 4468 Mallard is a London and North Eastern Railway Class A4 4-6-2 Pacific steam locomotive built in the 1930s by the LNER and designed by Sir Nigel Gresley in England. ... British Railways (BR), later rebranded as British Rail, ran the British railway system, from the nationalisation of the Big Four British railway companies in 1948 until its privatisation in stages between 1994 and 1997. ... Locomotives arranged around the turntable in the Great Hall. ...

Leader was originally seen as a great disaster. On January 18, 1952 the locomotive was front page news in the Sunday Dispatch Newspaper: in the paper’s opinion, Leader was a waste of £500,000. Nowadays, many believe, in retrospect, that the design could have changed transport history and prolonged the use of steam traction, had it not been scrapped before its time. January 18 is the 18th day of the year in the Gregorian calendar. ... 1952 (MCMLII) was a Leap year starting on Tuesday (link will take you to calendar). ...

External links

• “Leader” class locomotive