If you want my opinion or even if you don’t, I’m against mandatory radios.
However, if you fly at a busy airfield, it is good airmanship to have and use a radio,
(I have 2 in my Drifter) but they should never be relied on.
On a side note, at my airfield you can have 4 to 5 gliders as well as 4 to 5 powered aircraft in the circuit at one time. If every pilot calls Taxing, Lining up, Crosswind, Downwind, Base, Final and Clear of Runway, They become as good as useless. So how about using some commonsense, If you are near to or from a active airfield it is Good Airmanship to have and to use a radio. But please don’t hog the airways as there are only 4 calls that must be made.
* When the aircraft enters the "vicinity of an aerodrome"
* Immediately before joining the circuit pattern or, in the case of a straight-in approach, at least 5 NM from the threshold of the runway
* Immediately before, or during, taxiing
* Immediately before entering a runway.
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Kiwi.