British Railways 10800 was a
diesel locomotive built by the
North British Locomotive Company for
British Railways in 1950. It had been ordered by the
London, Midland and Scottish Railway in 1946 but did not appear until after the 1948 nationalisation of the railways.
The locomotive was designed by
George Ivatt
Henry George Ivatt (4 May 1886 – 4 October 1972), known as George Ivatt, was the post-war Chief Mechanical Engineer of the London Midland and Scottish Railway. He was the son of the Great Northern Railway locomotive engineer Henry Ivatt. ...
as a possible replacement for
steam locomotives on secondary and
branch line
A branch line is a phrase used in railway terminology to denote a secondary railway line which branches off a more important through route, usually a main line. A very short branch line may be called a spur line.
Industrial spur
An industr ...
s. The single-cab layout (
long bonnet forward) gave the driver a poor view of the road ahead. However, the driver's view was no worse than that from a steam locomotive cab, so it would have been acceptable at the time.
During its brief time on the
Southern Region between 1952 and 1954, 10800 gained the nickname 'The Wonder Engine', from the locomotive department's daily query, 'I wonder if it will go today'.
Description
Due to having been ordered by the LMS before the creation of British Railways (BR), 10800 became the first BR mixed-traffic diesel-electric locomotive when it was delivered in 1950. It was successful enough in operation for BR to order two classes of 54 similar locomotives in 1955 although these classes, destined to become the
British Rail Class 15
The British Rail Class 15 diesel locomotives, also known as the BTH Type 1, were designed by British Thomson-Houston, and built by the Yorkshire Engine Company and the Clayton Equipment Company, between 1957 and 1961. They were numbered D8200-D ...
and
British Rail Class 16
The British Rail Class 16 also known as the North British Type 1 was a type of diesel locomotive designed and manufactured by the North British Locomotive Company. A total of ten were produced, these being numbered D8400-D8409.
The type was or ...
, used the improved YHXL engine.
Extra Information
*Bogie wheelbase:
*Bogie pivot centres:
*Sanding equipment:
Pneumatic
*Heating type:
Steam (
Water-tube boiler
A high pressure watertube boiler (also spelled water-tube and water tube) is a type of boiler in which water circulates in tubes heated externally by the fire. Fuel is burned inside the furnace, creating hot gas which boils water in the steam-gen ...
) (
Clarkson thimble tube boiler
A thimble tube boiler is a form of steam boiler, usually provided as an auxiliary boiler or heat-recovery boiler. They are vertical in orientation and would be considered a form of water-tube boiler.
Description
The characteristic feature of th ...
)
*Main generator type:
BTH
*Aux generator type: BTH
*
Gear ratio
A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage.
Gear teeth are designed to ensure the Pitch circle diameter (gears), pitch circles of engaging gears roll on each other without slipping, pr ...
: 66:15
*Boiler water capacity:
*Boiler fuel capacity:*
Rebuilding as an AC transmission prototype
In 1961 No. 10800 was bought by
Brush Traction
Brush Traction is a manufacturer and maintainer of railway locomotives in Loughborough, England. It is a subsidiary of Wabtec.
History
Hughes's Locomotive & Tramway Engine Works
Henry Hughes had been operating at the Falcon Works since t ...
and rebuilt for experiments in
AC power transmission. Brush named the locomotive ''Hawk''. DC transmission in diesel-electric locomotives was reaching its limits, at least for single-generator locomotives. The brushgear and
commutator of a DC generator became prone to flashover for engine powers greater than around 2,700 bhp. The most straightforward solution, rather than redesigning the DC generator, was to adopt an AC
alternator
An alternator is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current. For reasons of cost and simplicity, most alternators use a rotating magnetic field with a stationary armature.Gor ...
instead, which could use a much simpler slipring connection to its field rotor rather than a commutator.
Although the advantages of AC transmission were obvious, the best means to implement suitable
traction motor
A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, elevators or electric multiple unit.
Traction motors are used in electrically powered rail vehicles ( electric multiple ...
s was not. Should these be the familiar DC motors (requiring AC–DC rectification)? Or should AC traction motors be developed, and if so, how would their speed be controlled? High-power solid-state electronics was in an early state at this time, although Brush were keen to become leaders in the field.
A more powerful engine would be required, to give a realistic trial, and Brush already had a suitable one on hand, as a spare from the development of
''Falcon''. This was a
Maybach MD655 of 1,400 bhp. The Maybach was also a high-speed
diesel engine
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...
, running at 1,500 rpm rather than the Paxman's 1,250 rpm. The Paxman was itself considered a high-speed engine, running significantly faster than the
English Electric or
Sulzer medium-speed (< 1,000 rpm) engines which had been adopted for high-powered British Railways locomotives. The new 100 Hz AC generator was rated at , a conversion efficiency of 91%. The output was at 1,325V / 600A. New AC traction motors were used, with
squirrel cage motors supplied by
thyristor
A thyristor () is a solid-state semiconductor device with four layers of alternating P- and N-type materials used for high-power applications. It acts exclusively as a bistable switch (or a latch), conducting when the gate receives a current ...
variable-frequency drive
A variable-frequency drive (VFD) is a type of motor drive used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and, depending on topology, to control associated voltage or current va ...
s.
Brush's experience with AC transmission, gained with ''Hawk'', would be put to use a few years later with the development of the 4,000 bhp single-engined AC transmission
HS4000 ''Kestrel''.
''Hawk'' was used until 1968, after which its control equipment was becoming irrelevantly obsolete and was superseded by the direct experience from ''Kestrel''. During the
1972 miners' strike the engine and generator were removed as a standby generator for the Brush Falcon works. After this, parts began to be stripped until it was finally scrapped around 1976.
References
Further reading
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External links
*
The Railway Raptors
{{British Rail Locomotives
* 10800
NBL locomotives
Brush Traction locomotives
Railway locomotives introduced in 1950
Scrapped locomotives
Unique locomotives
Bo-Bo locomotives
Standard gauge locomotives of Great Britain
Diesel-electric locomotives of Great Britain
Individual locomotives of Great Britain