DirectAnywhere, it is extraordinary that you don’t seem to understand my statement:
The reason that unalerted see and avoid incidents will be reduced in MBZ airports is because VFR aircraft flying enroute will no longer be monitoring hundreds of calls which are irrelevant.
This is a statement of fact. In the system before 27 November 2003, VFR pilots were taught to monitor ATC frequencies when enroute – that is why so many people want to keep the ATC frequency boundaries on the charts – and then were taught to change to the MBZ frequency when in the MBZ.
Unfortunately, the evidence appears to show that many pilots got to the MBZ and were then not on the correct frequency. This appears to be a greater problem in Australia (even though the requirement is “mandatory”) than in the US CTAF system, where the problem basically does not exist. They do not have a major problem of unalerted see and avoid at their non-tower airports.
There are two major differences. In the USA there is no requirement for VFR aircraft to monitor a radio when enroute. This means that the US VFR pilot can concentrate on monitoring the airport frequency. Also in the USA, rather than have some airports CTAFs and other airports MBZs, every non-tower airport is treated the same way. There are more self-announcements (seven, in fact) than in our MBZs, and the system results in a very high level of compliance and safety.
The reason we are moving to the NAS system for non-tower airports is not to save money. As you have rightly pointed out, there is no saving. It is to improve safety by reducing unalerted see and avoid incidents. In our system of “radio arranged separation” when VMC exists, the MBZ quickly overloads, and pilots cannot get an announcement in. With the NAS system, because there are more announcements and less dialogue, believe it or not, it can cope with more aircraft in the airport vicinity.
You appear to believe that by moving to NAS style CTAFs that there will be fewer pilots using radio. I do not agree, and if I thought this was the situation I would not support the introduction of NAS. I believe there will be no measurable difference in the number of aircraft using radios when existing MBZs are changed to CTAFs. However there will be less “diffusion of responsibility”, because pilots will be more vigilant.
You do not appear to understand the very great problems we have in existing MBZs. In December 2003, the ATSB completed a report (Airspace-Related Occurrences Involving Regular Public Transport and Charter Aircraft within Mandatory Broadcast Zones) where they made the following recommendation:
Some steps have already been taken in an attempt to increase the safety of aircraft operating within some MBZs. However, airspace-related occurrences within MBZs particularly those relating to radio usage, continue to be of safety concern.
****zu-Tonka, no I do not have an axe to grind with the ATSB. I’m happy that they declared the LT incident an airprox, however I believe it is important that they give the same amount of publicity to other airproxes which are just as serious or even more serious. If they don’t do this, there could be a false understanding that serious safety incidents have actually increased with the new airspace system, when they may have decreased.
The ATSB should be totally objective in their reports. I find it extraordinary that I have listed just some of the many incidents that have taken place over the last few years close to the airport, yet no system safety study has been done by the ATSB which mentions that we have a significant safety problem close to our airports.