Apologies for the continuing thread drift.
Dick,
"To provide a proper minimum safe altitude alerting service at Benalla would cost nothing."
If you are implying that to enable and SAFELY MONITOR alarms for Minimum Safe Altitude (MSAW),Route Adherence Monitoring (RAM),Short Term Conflict (STCA),Danger Area Infringement Warning (DAIW) at all aerodromes where radar may, or may not have full coverage, into ALL Aerodromes that have published approaches will not cost anything, then you are frankly talking out your backside.
Speaking to the controllers who work 45nm N of SY, to Coffs Harbour, there are published approaches for Kempsey, PMQ, Taree, Maitland and WLM (when RAAF not there, it would be there responsibility. Into CNK they use MLD approach til visual.
Controllers report that @90% of the time on approaches,RAM alert activates.
When querying acft about RAM alerts the reply is " Roger, we are now tracking for 5 mile final, etc".
Other comments include that even though 2 aircraft have been given traffic on each other , say into and out of PMQ, the STCA will still go off.This needs to be assessed to make sure it is the 2 aircraft that have been given traffic or some newbie popping up on radar.
Very basically, the STCA works on one aircraft with a Flight Data Record (FDR) in the system, the radar then assesses climb/descent profiles on other nearby aircraft around it to work out if a collision risk exists, and really starts screaming and flashing if it thinks so. It can be disabled below certain levels and in certain areas so it doesn't put more of us in the 'funny farm'.
As I stated before, the alarms don't go off to tell us something IS wrong, but the computer thinks something MIGHT be wrong.
Also they find that when trying to pass new, unidentified traffic to aircraft, that aircraft are usually already monitoring the CTAF frequency to gain situational awareness and find the interruption unhelpful, and sometimes do not reply at all. What is the controllers duty of care now? Continue on with the calls of course, further distracting the pilot as they are entering a critical phase of flight.
Throw in some vectoring, co-ordination calls to other units, a new A/TAF to pass to aircraft, some delay instructions, multiple aircraft doing Instrument Approaches, aircraft not acknowledging calls due cockpit workload, and it all adds up. The sectors would have to be shrunk to a SAFER, more manageable size.
Dick, when you were last in a Centre? When have you ever walked in our shoes? Funny though, I still enjoy talking to aircraft.
Disabling these alarms for an individual aircraft is not really an option. Think if you disabled an alarm , then another aircraft popped up. Alarm disabled, disaster occurs. Some years later off to Coroners' Court to explain your actions to highly paid legal types, armchair experts commentating in the Media, you always second guessing yourself about what you may have done different, distraught relatives, and even if you believe your actions were reasonable you still have to live the rest of your life with the knowledge that you have played a part in the death of other human beings.
Food for thought?
Last edited by max1; 25th Sep 2008 at 11:22.