This unusual unit was built for the Jubilee Line extension of the London Underground back in 1994 and used by the contractors who re-laid approximately two thirds of the South Line in conjunction with the I.R.I.S. project from 2000 onwards.

This was an all-island sewerage scheme which saw a main pipeline being laid beneath the railway in 2000-2002 resulting in shuttle services being operated across a number of seasons - dubbed I Reckon It Stinks by its detractors! 

The locomotive was bought from the contractors upon completion of the work and named in honour of Lord Ailsa, who had greatly contributed to the railway in the late 1960s, a ceremony unveiling this name took place in 2005. 

It was stated at the time that it would receive green livery (sometimes known as “Ailsa Green” as it was standard at the time of his ownership) but it remained in plain white, until removal of some of its ballast weights which has resulted in a red oxide lower half with a white upper.

It was not until the end of 2024 that work began on a full repaint, but into a deep (Fordson) blue scheme largely at the behest of a tractor-enthusiast member of the team who, echoing the late David Howard with Cale, “happened to rather like it”!

This accounts for the somewhat squat appearance, although the cab was extended upwards before its arrival on island.  This also results in limited visibility for the driver which has seen it fitted with closed circuit television cameras to aid vision.

However, this disability as well as the absence of a continuous train braking system (in this case vacuum brakes) and also a mechanically governed top speed of around sixteen miles per hour, top line speed being twenty-five.

This ensures it is used largely on shunting and permanent way duties being unsuitable for passenger workings; it remains in regular operation and is used for shunting each morning at Douglas Station, often to be seen in and around the yard and used for additional carriage strengthening trains on busy days.