Originally Posted by
nose,cabin
“commit to destination”,Alternate fuel
You're right that Australia has quite different alternate requirements, BUT
Alternate Airport,
fuel calculation includes missed approach at the destination airport, ( both engines operating,)
, complete the missed approach procedure, climb, cruise, descent to alternate airport, and 15 minutes reserve.
No taxi fuel at destination,
When ATC holding is required
The latest TTD time is provided to ATC.
This becomes the diversion time allocated by
ATC.
Clearances are ready and issued prior to diversion time.
Never loose plan B.
Only when an alternate is required, which is the small minority of flights in Ausrtralia