It looks a little like a Jet Provost. I can't find it looking on Google Earth itself; can you describe where on the airfield the aircraft is.
Ignore that, now found it and is definitely a Jet Provost T5. One of the training aircraft on which I started my RAF flying training in the mid/late-80s.
It's in front of Gama Aviation who provide contracted services to the UK military and was probably bought as a 'Gate Guardian' as displayed at the entrance to many RAF stations.
A more detailed image.