DR1 Driver,
It was the Catton Hall Garden Party Fly-in.
Catton Hall is the the home UK WW1 Flying Circus Display team - we have been flying at various model displays all over the country for many years - all with 1/4 scale WW1 aircraft.
At one show we managed to get 15 WW1 a/c in the sky together (rather busy) and it often descends into a mass dogfight (which is as much fun as you can have with your trousers on!).
Attached is an evocative photo of my father's & mine Triplanes.
Dad's is in the forground - mine is behind and on top.
VBR
Jason