Aeronautical Study of Port Macquarie - Civil Aviation Safety Authority

Office of Airspace Regulation Page 46 of 69
A/c1 (V, L, M or H) V L L L M M M M M H H H H H H H
A/c2 (V, L, M or H) V V L L V L L M M V L L M M H H
VMC or IMC V V V I V V I V I V V I V I V I
RISK REDUCTION SERIES 1 (Percentage compared to base case = 100 (98 is little reduction 12 is much risk reduction))
Basic CTAF 95 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
CTAF 95 wirth DTI 99 98 76 76 99 68 68 91 91 99 68 68 91 91 91 91
CTAF 95 with AFRU
& CAGRO 54 49 66 66 45 49 49 42 42 45 49 49 42 42 42 42
Basic MBZ 38 33 100 100 26 100 100 100 100 26 100 100 100 100 100 100
MBZ with DTI 38 32 76 76 26 68 68 91 91 26 68 68 91 91 91 91
MBZ with AFRU &
CAGRO 27 19 66 66 12 49 49 42 42 12 49 49 42 42 42 42
MBZ with AFRU,
CAGRO & DTI 27 19 59 59 12 39 39 39 39 12 39 39 39 39 39 39
RISK REDUCTION SERIES 2 (Percentage compared to base case = 100 ((98 is little reduction 12 is much risk reduction))
Basic MBZ 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
MBZ with DTI 100 97 76 76 99 68 68 91 91 99 68 68 91 91 91 91
MBZ with AFRU &
CAGRO 70 59 66 66 46 49 49 42 42 46 49 49 42 42 42 42
MBZ with AFRU,
CAGRO & DTI 70 59 59 59 46 39 39 39 39 46 39 39 39 39 39 39
Table 6 – Risk Reduction Series Note Mandatory Broadcast Zone (MBZ) now known as CTAF(R)
In Table 6, Risk reduction Series 1 commences with the Basic CTAF 95 set at = 100
and calculates the risk reduction from various cases. For IFR(H)-VFR in VMC (HVV)
for example:
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Basic CTAF 95 100;
with DTI 99;
with AFRU and CAGRO 45; and
with CTAF(R) 26.
Taking MBZ-CTAF(R) as the base case, note that all of the CTAF options are less
safe than CTAF(R).
For CTAF(R) base case:
CTAF(R) 100;
with DTI 99;
with AFRU and CAGRO 46; and
with AFRU and CAGRO and DTI 46.
The DTI case applies only to IFR-IFR pairs and provides reasonable risk reductions
by ensuring that IFR(L) are known to IFR(M) and IFR(H) especially in IMC
AFRU & CA/GRO essentially reduce risk across the board by 50%. This would
reduce the IFR(H) – VFR point on the graph to closer to tolerable than scrutiny.
A more detailed examination of the ARM would be required to determine the
individual contributions of AFRU and CA/GRO.
The ARM also provides insights into the operation of TCAS and transponders. TCAS
is a particular implementation of Airborne Collision Avoidance System (ACAS). ACAS
is designed to provide a Traffic Advisory (TA) alert at 45 seconds from closest point
of approach (CPA); a mandatory Resolution Advisory (RA) at 25 seconds and, if the
threat persists, a reversal.
Airspace Review of Port Macquarie (YPMQ) May 2010 Version 1.0