John Buchan, aka Jimmy from the BBC series Trawlermen, spotted the flames first, before hearing the sirens of fire engines.
He took this video at around 5.30am as around 40 firefighters made their way to the Ardent INS to battle the blaze at Port Henry Harbour in Peterhead.
Police, the coastguard and Peterhead RNLI lifeboat team are also in attendance.
No one was on board and the three crew members were accounted for.