What operated British Rail 10800 in Mar 1961?
British Rail 10800 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 . Design was by George Ivatt and the locomotive was intended as a possible replacement for steam locomotives on secondary and branch lines . The single-cab layout ( long bonnet forward ) gave the driver a poor view of the road ahead . The view was no worse than a steam locomotives , so it would have been considered 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 departments 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 . Operationally it was successful enough for BR to order two classes of 54 similar locomotives in 1955 although these , destined to become BR Class 15 and BR Class 16 , used the improved YHXL engine . Extra Information . - Bogie wheelbase : - Bogie pivot centres : - Sanding equipment : Pneumatic - Heating type : Steam ( Water-tube boiler ) ( Clarkson thimble tube boiler ) – Clarkson - Main generator type : BTH - Aux generator type : BTH - Gear ratio : 66:15 - Boiler water capacity : - Boiler fuel capacity:* Rebuilding as an AC transmission prototype . In 1961 No . 10800 was bought by Brush Traction 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 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 motors 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 , running at 1,500 rpm rather than the Paxmans 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 100Hz 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 variable-frequency drives . Brushs 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 . External links . - The Railway Centre - The Railway Raptors