Alphacentauri - great posts - absolutely agree with discussion airspace systems rather than classes. A good case example is the work going into autonomous cars - there will be no 'airspace class' for them as the hive will be left to sort it out - an airspace system if you will. How long it takes to get there is another question but ultimately it will have to - society will demand it. TCAS is another great example - works irrespective of airspace class but is an airspace system.
The risk framework can ultimately be developed by looking at a simple financial equation - the cost of not mitigating a risk vs the cost of mitigation. The cost of mitigation can be determined easily enough (unless Airservices are managing the implementation....
). The cost of not mitigating is what actuaries are paid to do and is no different to the process of determining your insurance policies. The key item is the cost of life. Various organisations attempt to quantify the cost of life including here in Oz where the government in 2014 valued 1 life at $4.2m. (
"Best Practice Regulation Guidance Note: Value of statistical life"(PDF). Department of the Prime Minister and Cabinet. December 2014 - with thanks to Wikipedia for the link).
So using the two examples above.
Mangalore - allowing for inflation plus arguably some additional costs relating to ATSB investigations, emergency services responses, destroyed aircraft, and intangibles like reputational damage (yeah I know - could be used to manipulate any answer you want) - lets say 4 casualties + extras = $20m in todays money. Lets also say that Managalore was a 1 in 20 year event - or even 1 in 50. What solution exists that costs $1m or even $400k? per annum?). (I know - mandated, federally funded ADSB-IN transponders for all IFR aircraft? Enough overtime to staff a second set of eyes at ML CTR watching YMNG during training hours? Enough to establish a new control position including frequencies etc during YMNG training hours?)
Ballina - hasn't happened yet but lets assume that sometime in the next 90 years - call it a 1 in 100 year event given we've gotten through the last 10 unscathed. At a cost of, say, $5m * 120 people plus a new airbus plus etc gets you close to $700m. What could you do at Ballina for $7m per year? Quite a bit I imagine. Extend the model to all similar airports in Oz and say its a 1 in 50 year incident and you have $14m/pa to spend across all similar airports. Going to pay for several new ATC positions plus increased radar coverage where required?
So the ability to price risk around human lives exists - agree or disagree with it. But it's far from perfect as statistics and particularly risk assessments I often find are geared to generate the desired answer particularly by manipulating the likelihood of an event. The distribution & skew of the costs of not mitigating are also horrendously vague - but it shouldn't be beyond the wit of man (or Airservices or ORR) to develop the framework based on fairly common methodologies and good worldwide data on expected accident rates that have good data behind them due to the nature of aviation investigation and reporting.
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