60103 "Flying Scotsman" near Bicester in June 2018. ©Peter Trimming
In 1928, after the success of the A1 class, the LNER introduced what was to become the iconic A3 class of 4-6-2 express passenger locomotives. They were built to run on the whole length of the East Coast Main Line from London Kings Cross to Edinburgh Waverley, some services running non-stop. The most famous of these locomotives was the 'Flying Scotsman', the locomotive being named after the train which ran non-stop daily North from Kings Cross.
This was the longest non-stop service in the UK and really tested both the locomotive and crews (2 were used for each run, changing over via the corridor tender) and much use of water troughs was made. The locomotives received relatively few modifications in their lives, the main one being the tenders of which there were corridor and non-corridor versions depending on the intended use of the locomotive. The only other big modification was to the boilers, with higher pressure boilers being introduced, the main visual indication being the larger 'banjo' dome fitted to these. Some A3's were also fitted with German style smoke deflectors to help improve the drivers view when double chimneys were fitted.
Most A3's lasted until 1963 with a few lasting until 1965 and one until 1966, by this time some being relegated to more mundane freight duties as the diesels took over the front line passenger services. One A3 has been preserved, Flying Scotsman, and is now owned by the National Railway Museum.