Who is responsible for designing a Sqdn crest? Is it someone 'volunteered' by the CO? Most of the ones I have seen are quite good.
A friend of mine, the late Dennis Endean Ivall, was a talented heraldic artist and although originally a Londoner was a Cornish speaker and a Bard of the Cornish Gorsedd. He was asked to design the badge of 2625 (County of Cornwall) Squadron, RAuxAF Regiment, which was based at RAF St Mawgan until its disbandment in 2006. The badge is shown here.
2625 History
The Badge of 2625 Squadron that received Royal Approval in 1989 shows a bayonet superimposed on the cross of St Piran, the patron saint of Cornwall. The Squadron motto was Onen Hag Ol (One and All).
As far as I know this was the only RAF unit to have a motto in the Cornish language.