This question re-activated a memory in my failing mind. Back in 1974,while in the VIth form,I took an ' O level 'in Air Navigation,which was taught by our art teacher,Terry Jones,who was CO of the local ATC squadron,and had trained as a Pilot with the RAF in Canada,and then flew F86 Sabres.However,after a career in ATC,and knowing a lot of people involved in flying and aviation,I never met another person who admitted to having an 'O level' in this subject.Are there any others out there in PPruneland with this qualification ?