4.9 Joining on base leg
4.9.1 Joining on base leg, whilst not prohibited, is not a
recommended standard procedure, i.e. CASA recommends pilots
join the circuit on either the crosswind or downwind leg. However,
pilots who choose to join on base leg should only do so if they:
• have determined the wind direction and speed;
• have determined the runway in use;
• give way to other circuit traffic and ensure the aircraft
can safely (no traffic conflict likely) join the base leg
applicable to the circuit direction in use at the standard
height (refer to paragraph 4.3.1 above); and
• broadcast their intentions.
Note: Base leg joins must be conducted in accordance with the
circuit directions as published in the ERSA.
I think many people should take note of this extract from the upcoming CAAP regarding base joins.