Two queries for the experts:

(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 6.1.16.2).

(2) Where can I find a definition of "in the vicinity of the aerodrome"?

Thanks,

Haydn

There are two different definitions of vicinity. For the sake of aerodrome traffic, vicinity is within 10nm.
CAR 166 (c),
AIP ENR 1.1 Page 54 para 6.1 (Note 4),
AIP Gen 2.2 Page 17.

For the purpose of Met messages vicinity is beyond 8km but less than 16km.
AIP GEN 3.5 para 12.110.5.

There is no specific requirement for a downwind call at a non-controlled aerodrome.

Thank you. I had looked at GEN 2.2 Definitions but was searching under "vicinity", not "in the vicinity"!