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(1) AIP ENR 1.1 2.12.4 specifies a downwind report is required in CTA. Is there a similar requirement for when OCTA?
Some aerodromes do not require the carriage of radio, so a downwind call cannot be mandatory in all cases. Other than good airmanship and the general requirement in CAR 166C to make a broadcast wherever reasonably necessary to avoid a collision, is there any provision in the AIP that explicitly mentions a downwind broadcast when OCTA? Something similar to the 10NM broadcast when inbound (per AIP ENR 1.1 220.127.116.11).
(2) Where can I find a definition of "in the vicinity of the aerodrome"?