Originally Posted by
Lead Balloon
The provenance of the broken circle on Australia’s charts remains a mystery. And, given that the legend of the Australian chart says a broken circle denotes that the place is unverified, the point of adding the ‘U’ remains a bigger mystery.
Does the broken circle denote 'unverified' or 'uncertified' aerodrome? I don't have a chart at hand, but it should be the latter.