A major military exercise involving more than 50 aircraft is in full swing at RAF Waddington.
Cobra Warrior – which has attracted spectators from around the country – is designed to train RAF personnel in tactical air war operations.
Nato allies are also taking part in the annual event, including Canada, Poland, Finland and Norway.
Participants took to the skies above Lincolnshire on 16 September, with the exercise due to continue until 4 October.
Wing Cdr Colin Melvin, who commands the operation support wing at Waddington, said: “It’s a lot bigger for us than it has been for a number of years.
“We’ve got multiple fast jets and multiple heavy aircraft supporting.
“It’s always great to see our Nato allies and partners here and get the opportunity to train together.”
Lt Col Ben Switzer, of the Canadian detachment, said the exercise offered a “unique and challenging experience”.
Staff from Waddington are running the operation, while aircrews from RAF stations at Lossiemouth, Brize Norton, Coningsby and Lakenheath are taking part.
Aviation enthusiasts have flocked to Waddington to watch the planes.
John Smith, 83, from Nottingham, who attends the exercise every year, said: “I’m quite surprised by the number of people, it never used to be this busy.
“It seems everybody wants to come have a look.”
Antony Hodges, 60, from Somerset, drove four-and-a-half hours to watch the planes fly over.
“It’s always worth the drive, it’s a great atmosphere and everyone is excited. I’ve come to see the Polish planes,” he said.
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