With two enthusiasts enjoying the Napier soundtrack 55002 'The King's Own Yorkshire Light Infantry' makes a sedate departure from York station leading the 1A26 15.50 York to King's Cross semi-fast service. Looking at the exhaust pattern it would appear that the Deltic is only running on one engine, something that they spent a lot of their time doing in their final years of operation. The photograph is taken under York's Holgate bridge where access so close to the line was tolerated back in a world when common sense prevailed.
There is an audio recording of this event on my youtube channel, see....
https://youtu.be/UqCqHD4nUps