How drones are hunting fires hidden beneath the Cairngorms

It is 06:00 and I'm meeting drone pilot Pete Short for a dawn patrol in the Cairngorms National Park.

It is a job he has been doing for almost three months, since a huge wildfire tore through this landscape in July.

The flames which swept across the hillsides are gone. From where we are standing, there is little to suggest there is still a fire here at all.

After a bumpy drive into the woodland, Pete launches a thermal drone into the early morning sky.

I am given a job too: keeping the aircraft in sight while he studies the images being sent back to his screen.

"Every week I hope that I find none," he tells me. "On the last thermal flight I did we found eight."

"We might have something here," Pete says, as a white glow appears on the thermal image beneath a tree.

Three months after the fire first ignited, heat is still being detected beneath the ground.