2018 was the centenary year of the RAF (which was formally created on 1st April 1918) and to celebrate this a genuine ex-RAF steam locomotive, bought by the RAF shortly after its formation, was repainted in RAF colours to work both its and the RAF's 100th birthday. The engine is now the Tallyllyn Railway's no 6, normally simply rejoicing in the name "Douglas" but for the occasion also sporting its original identity of "Air Service Constructional Corps no 1" as it was at RAF Calshot, the base on which it worked at the Solent end of Southampton Water. It was built by Andrew Barclay Sons & Co Ltd as their works no 1431 to their standard class E specification. Here we see the engine coming "off shed" at Pendre with two other Tallyllyn locos (nos. 1 "Tal-y-llyn" and 3 "Sir Hadyn") and then pausing in the loop at Quarry to take the token.