2B1,
This is text from the official CASA documentation on the approval of the Design Safety Case...
CASA has reviewed the Design Safety Case (DSC) dated 1st September 2003 and makes the following comments:
1. The DSC identifies 10 ‘characteristics’ to be changed in Stage 2b, 7 of which are assessed as being not compliant with the US FAA/NAS model and thus subject to the Design Safety Case requirement.
2. The detailed evaluation of the presented DSC evidences that the Stage 2b implementation will bring about an increase in risk beyond that which exists in Australia today, but CASA is unable to determine the degree of this additional risk from the material supplied in the DSC.
3. CASA believes that the US FAA/NAS model is safer than the existing Australian airspace system. Therefore, any increase in risk over the existing airspace system will also be a greater risk than the US FAA/NAS model.
4. The DSC states that each airspace design and each procedure is safe.
5. Material supplied to CASA by NASIG claims that it is necessary for the full implementation of the Australian NAS that Australia transition through this interim stage.
6. Based on the statement contained in paragraph 4 above, the expectation that full implementation of the NAS will provide a significant decrease in risk and that appropriate risk mitigation strategies are in place in the interim, CASA has no objection to NAS proceeding to the next phase.
7. CASA is not amenable to these transitional arrangements remaining in place for an extended period and requires advice as soon as practicable when the transitional arrangements will end in accordance with the NASIG Terms of Reference (IG Task 4c).
I think we can draw from that text: (my slant from the weeds)
Point 1 AUSNAS isn't he same as USNAS.
Point 2
Stage 2b implementation will bring about an increase in risk beyond that which exists in Australia today
Point 3 This phase of implementation is increasing the already higher risk.
Point 4 Each element is safe; but is it safer, not at this phase...
Point 5 We are sure that end state will be safer than what we will have in November.
Point 6 Bring on the next phase, fast, we don't like this one...
Point 7 Hurry up... We think staged implementation sucks...
Bottle of Rum