How do allied forces tackle refuelling in the skies?

The challenges of refuelling in the sky have been shown in new footage from NATO.

The video shows how the allies accomplish the dangerous but essential part of the mission in the skies – with the help of a French refuelling aircraft.

Refuelling mid-air, or air-to-air refuelling (AAR), is the transfer of fuel from one aircraft, the 'tanker', to another aircraft, the 'receiver' in mid-flight.

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Aerial refuelling is one of the most demanding and high-stakes operations in the sky, where mistakes can lead to fatalities.

The large aircraft have to fly at exactly the same speed and maintain the same relative positions only a few dozen metres apart – even at night and in severe turbulence.