Like you Pobjoy - I used to drive past Chattis Hill regularly,it was one of my 3 alternative routes either between Old Sarum (Gliding) and home (w sussex) or B Down and home (W Sussex - in a later working life LOL),visited a few old airfields/locations over the years and checked many out from the air in my Libelle 201b which was based at O Sarum in the late 80's.