In pictures: Commando Helicopter Force learns Arctic warfare during Operation Clockwork
Two hundred Royal Navy personnel have learned how to fight and survive in the cold during Operation Clockwork north of the Arctic circle where temperatures could fall to -30°c.
Naval chefs, ground and air crews, helicopter engineers, and logistics experts from the Commando Helicopter Force have endured intensive training in Arctic conditions at the Bardufoss air base in Norway as part of an operation that will prepare them for winter warfare. The training is like that of the Royal Marines.
Merlin engineer Petty Officer Rich Miszewski-Hall said: "This is the first time I had done the specific cold weather course for the aviation world. I completed the basic survival training eight years.
"This time around I found it a lot more challenging – mentally and physically – especially having to just crack on through the lack of sleep. The camaraderie was great throughout, which did help a lot.
"Finishing with the ice-breaking drills was a treat. It was a little colder than I remember but refreshing after five nights of living in the field."
During training, naval personnel slept in tents and lived off the land to ensure they could support, maintain, and operate their aircraft in the extreme cold.

They also had two days of survival lessons in classrooms before heading out into the sub-zero conditions.
The field aspect of training involved them spending six days in the cold where they practised trekking through deep snow, surviving avalanches, patrolling, living without rations in tents, and building makeshift shelters.
The Somerset-based Commando Helicopter Force deploys in strength for Operation Clockwork each winter.

Merlin pilot Lieutenant Andy Duffield said: "The Arctic environmental qualifications are under way now, exposing aircrew to the extremes of snow landings.
"By day isn't for the faint-hearted but, by night, it's true Commando Helicopter Force stuff.
"Would we have it any other way? If it ain't snowin', we ain't goin'," he added.