Preventing Mid-Air Collisions

Statistics show that flights involving airfield circuits are a risk area for mid air collisions.   It is clearly therefore good  airmanship to call aerodromes marked on the chart even though the airfield doesn’t have an ATZ or other annotation (i.e. ‘T’ or ‘U’) before overflying at circuit height or passing close enough to be in the likely visual circuit as a way of mitigating the risk of collision. If there is any doubt, why not simply plan to avoid said aerodromes by a safe distance?  A case in point is Henlow which is quite a busy place open from 0800 - 2100 hours daily with over 30 resident aircraft and that has an A/G freq of 121.000MHz.  Despite the availability of the A/G station which could have advised whether there were any movements taking place, fifteen aircraft flew through the Henlow circuit in the last month at circuit height without making radio contact.