The role of 55018 Ballymoss is being played by 55022 Royal Scots Grey

Built around two hugely powerful Napier "Deltic" engines, a development of a naval engine fitted to World War 2 torpedo boats, the Deltics were built in 1961 and 1962 to replace the famous streamlined A4 Pacific class of steam locomotives on the prestigious London-Edinburgh route. 22 were built and soon brought the average London-Edinburgh time down to under 6 hours, regularly topping 100mph in the process. As the East Coast Main Line was upgraded, so timings dropped still further with the Flying Scotsman limited-stop service clocking in at 5h30m by the late 1970s.

In 1978, the "High Speed Train" (HST) was introduced and the Deltic's days were numbered - first relegated to hauling the sleeper services (as briefly immortalised in an early episode of Yes, Minister) and fast mail and parcels services, before eventually being withdrawn entirely in 1981-82.  The 22 locomotives were named either after racehorses or regiments, both naming themes popular in steam days, and six were preserved in working order as well as two cabs and the pre-production prototype at the National Railway Museum. The Deltics have become a favourite in preservation and even many of the most hardened steam buffs will admit a sneaking admiration for the sheer grunt of the big engines.

D9000 was numerically the first of English Electric’s production Deltic locos to emerge from Vulcan Foundry in Newton-le-Willows 1960. In August 1961, D9000 is recorded as hauling the up Flying Scotsman from Edinburgh to Kings Cross for the first time. In June 1962 she was named at a ceremony at Edinburgh Waverley station. D9000 became 55022 during an overhaul at Doncaster in 1974. She spent the majority of her working life stabled at Haymarket, with a brief stint at Finsbury Park in 1967-68.

55022 continues in service to the bitter end, hauling the Deltic Scotsman Farewell railtour from Edinburgh to Kings Cross, becoming the last Deltic to work for BR. Preservation followed, initially at the Nene Valley Railway and then, in November 1996, “Royal Scots Grey” became the first preserved Deltic to operate on the main line once more. From 1997-2002 she was leased by Anglia Railways and Virgin Trains to provide a backup for regular passenger services.

The locomotive was initially preserved by the Deltic 9000 Fund and its successor Deltic 9000 Locomotives Limited, before being sold to Beaver Sports (Yorks) Ltd, its current owner in 2004. In 2015, the locomotive was repainted with the white cab window surrounds typical of the Finsbury Park depot and has been seen in the guise of a number of locomotives based there; 55003 Meld, 55007 Pinza and, currently, 55018 Ballymoss.

She is currently on long-term loan at the railway and will be rattling the china in offices and houses along the line throughout the season.