Are you absolutely certain that it’s not Lasham? There are pictures of a Redcoat CL-44 elsewhere on the internet that claim to be at Lasham in summer 1980 and visible in the background of your photo are a Dan-Air Ambassador and what looks to be an Avro York, both of which were at Lasham until they moved to Duxford in 1986. The 727 is also in an early 80’s colour scheme.