The driver has just opened the power handle on 50013 'Agincourt' at Aller Junction. The train had been held at the signal for a short time so the driver would have been eager to get away heading onwards to either Plymouth or Penzance. 50103 has its high-intensity headlight fitted meaning that it has gone through Doncaster works as part of the Class 50 overhaul programme. Indeed, it had left the plant only two months previously and would remain in service for another eight years receiving its large logo livery in between.
There is an audio recording of this event on my youtube channel, see.....
https://youtu.be/-QL7oNWtYEg