Ian, Why can't we follow the NZ line. Works with two organisations very well.
Have CASA take over the aircraft registrations (VH-xxx) of ALL aircraft in Aus.
This would ease the current problems we have with "Registrations". If run by CASA then it must be right!
If CASA want to distinguish between GA and Ultralight registrations then have all ultralights as VH-U(uniform)xxx or something similar although this does not happen across the ditch.
As in NZ register the aircraft as class 1 (single seat) or class 2 (two seat) ultralights with an up to 600KG MTOW.
As in NZ allow training in class 2 wether amateur built or factory built as long as the engine etc is not out of the manufacturers stated TBO.
Pilot certificates can still be issued by either RAAus or a second organisation. In NZ this is RAANZ or SAC.
RAANZ is more like RAAus and SAC a company type set up.
Aircraft maintenance is still done by the owner IF he wishes and an annual inspection is carried out by a RAANZ or SAC authorised inspector a bit like our L2 etc.
There is NO annual fee for registration however there is an airways "activity" fee of around $100.00 PA I believe payable to NZCAA as the Safety Authority.
My pennies worth
Cheers