So if there’s no ‘bandwidth’ issue or ‘orphan system’ issue with 1090ES ADS-B, there is no technical, regulatory or practical constraint or downside (other than cost) in installing the system in an Australian aircraft
There is the fact that ASA/CASA don't own the GPS system. Nor do they control the GPS system. Also they have no written guarantee that the GPS system will be available for use at a future time. Apart from that its all happy smokes..
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