What to wear on a Franz Josef helicopter flight

You take off from a village at about two hundred metres, in rainforest, often in warm still air. Twelve minutes later you step out onto a snowfield near two thousand metres with wind coming off the Alps. Nothing about the village prepares you for it.

The most common mistake is footwear. Sandals and thin trainers are fine in the cabin and miserable the moment you put a foot into packed wet snow, and people end up spending the ten minutes standing on the skid instead of walking around.

The second is sunglasses. Snow at altitude under a clear sky is genuinely painful without them, and there is no shade on a névé.

Boots, crampons, a waterproof jacket and overtrousers come with every guided heli-hike. They are fitted at the base before you fly and they are good gear.

What they do not provide is warmth. The jacket keeps wind and water out; the layers underneath are yours. A thermal top, a fleece or light down layer, and gloves. You are on the ice for two and a half hours and you will be standing still for parts of it while the guide cuts steps.

Sunscreen matters more than it sounds. Reflected light off ice burns faces in a way flat ground does not.

These aircraft carry four to six people and the pilot balances them by weight. A large bag is a problem for the loading and there is nowhere to put it. Most operators ask you to leave luggage at the base, and there is a locker or a shelf for it.

A camera and a jacket is the sensible load. Loose hats and scarves are worth securing — rotor downwash takes them.