LeadSled
by definition of the design principles, once the separation assurance standard is achieved, higher classes of airspace will not achieve a real reduction in risk, because the separation assurance standard is already so high. Whether you agree or not is immaterial, that is no more than your personal opinion.
ICAO Doc 9689 Chapters 5 and 6
5.2
Comparison with a reference system is a “relative” method, i.e. all the relevant characteristics of a reference system are compared with the corresponding characteristics of a reference system which has been judged to be safe. Provided that the proposed system can be demonstrated to be similar to or better than the reference system in all safety related aspects, then it also may be assumed to be safe. Clearly, the most important aspect of this approach lies in the identification of a suitable reference airspace which, for minor changes, may include the current system and the demonstration that the proposed system is sufficiently similar to justify the approach.
6.3 Whatever reference system is chosen, it must bear a sufficiently close resemblance to the proposed system for any comparison with regard to safety to be valid. The levels of air traffic service provided in the reference and proposed airspace, as defined by the ICAO airspace classifications, should be examined. The air traffic service in the proposed system should provide at least the same level of service as the reference system.
- Tower frequencies and operating positions?
- Approach and Departures frequencies and operating positions?
- Surveillance?
6.4 The minimum requirements for a reference system to be considered sufficiently similar to a proposed system are:
a) separation minima must not be less in the proposed system than in the reference system;
b) proposed means of communication and surveillance must be no worse in terms of accuracy, reliability, integrity and availability than those of the reference system;
c) frequency and duration of the application of minimum separation between aircraft must not be greater in the proposed system than in the reference system; and
d) navigation performance 9typical and non-typical) of the population of aircraft in the proposed system should be no worse in it effect on collision risk, in any dimension, than that of the aircraft in the reference system.
The previous comparisons in this thread of the US and Australian systems completely eliminates this option as a valid comparison.
Risk reduction measures
6.24 Risk reduction measures should be used when the overall risk estimate is above the predetermined threshold and when a particular element of the system is found to have a disproportionate influence on the risk, providing this can be achieved at an acceptable cost. The detailed process of risk reduction procedures by allowing the effect of changes to the various system parameters to e directly assessed.
Appendix 10 of ICAO Doc 9689 refers to the Australian Risk assessment processes.
Where are the risk assessments for YWLM, YMAV, YPKA and YBRM??
I would caution you
LeadSled against quoting risk probabilities in this thread that are not reflected in the Australian and ICAO documents.
Indeed, several orders of magnitude higher ( lesser risk) than losing a complete aircraft on an auto-couples Cat II/III approach
Precision approach navigation, both ground based installations, calibration and airborne equipment installation, certification, and training is a COMPLETELY different ball park in so far as treatment of risk [IMC to very low, and avoiding meeting terrain in the wrong location] compared to airspace services risk assessment [MAC and NMAC mitigation].
ICAO Doc’s 9906 Vol 1 thru 3 set out in clear and concise term the Procedures Design and QA requirements [due the criticality of those operations close to the surface].
The risk treatments are completely different for obvious reasons, and moreover of no relevance to this discussion. Your arguments are approaching ‘the ridiculous’ when you have nothing left but to attempt to be ‘relevant’ by comparing ‘irrelevant’ structures in place to facilitate poor weather continuation of IFR flight with that of ATS and airspace services.
Seeing as you raised it, let’s explore the differences:-
or the probability of an aircraft CFIT (without regard to GPWS) during an approach (or departure) designed to current PANS/OPS standards ---- all the above have had a core element of risk management built in for many, many years.
Correct.
Procedure design and operation [ICAO Doc’s 8071, 9137, 9157, 9184]
- Expert designers, draft
- Expert Calibration pilots test fly [in VMC of course] to check accuracy and veracity
- Approach plates promulgated, procedure commissioned
- Real time ground monitoring of NAVAID signal accuracy and serviceability
- Real time redundant power supplies [Mains, Battery, and autostart GENSET’s]
- Regular [interval dependant on criticality] flight testing calibration [in VMC]
- Real time airborne monitoring of ‘correct’ NAVAID selection
- Real time airborne monitoring of signal serviceability [flags]
All of those ‘mitigations’ enable FULL AWARENESS AT ALL TIMES of the safe useability of the procedure and therefore safe flight to close proximities with the surface, surveyed as per PANS/OPS for obstacle clearances.
Airspace design risk assessment and operation
- See PPRuNe –
NAS raises it head again thread
- See ICAO Doc’s 4444, 7030, 9426, 9643, 9689, 9859, 9882, 9924, 9925, 9931 and others
- See The Act, The AAPS, The CRMF
- See the publically available volume specific Cost and Safety benefit Studies comparing Class E over D, D over D, and C over D
Red Flag – Nil Available for YWLM [RAAF N/A], YMAV, YBRM, YPKA
- See the publically available volume specific Risk Assessments comparing Class E over D, D over D, and C over D
Red Flag – Nil Available for YWLM [RAAF N/A], YMAV, YBRM, YPKA
Clearly, I am quite happy to accept the ICAO approach to risk management.
Fabulous, let’s remember that whilst we read on:-
That the basics of ICAO airspace design is not accepted by a range of pilots and ATC individuals in Australia says more about Australian aviation attitudes to modern risk management, than it says about the veracity of the basic ICAO risk management standards.
ICAO airspace design and procedure to validate is EXACTLY what pilots and air traffic controllers in Australia are demanding. It is unacceptable for you to continually misrepresent the discomfort being expressed by them. It is clear that it is not only not only being expressed by commercial aircrew and air traffic controllers, but also representatives of and individuals from within the general aviation sector. That in my book is pretty close to a full house. Does a pair of low spades then win the hand? You keep suggesting on this thread that the answer is yes, and solely because the
’slight of hand’ by the dealer at
‘Skull Casino’ is all that counts! WRONG!
Too many people have been duded for too many years to fall for that card trick anymore!
Strangely, pilots don't complain about the hazard levels in instrument procedure design, but the inherent hazards and the mitigators employed to reduce the final risk, still leave a level of risk that is not ALARP, as most of you interpret ALARP.
Strangely, as explained above, that is a load of cougar pellets. You continue to avoid the critical word within A.L.A.R.P, and that word is
Reasonably. Pilots don’t complain about hazard levels in instrument procedure because the hazards are a mitigated to a point where
it requires a series errors for the instrument approach flown to fail unsafe resulting in a hull loss. By contrast, as is demonstrated with regular monotony in Class E [in various countries], it does
not require an error or chain of errors to fail unsafe. It is inherently less safe that D, C, B and A in ‘normal’ operation.
The fact that the fail unsafe opportunity is reduced dramatically by having VFR operating within ‘the system’ [Class D or C] where climb and descent risk is greatest to passenger transport operations, the
‘reasonable’ test comes down to this:-
1. The cost difference is demonstrably nil [Current Australian C over D practices]
2. The impost to VFR is simply using a radio and complying with a clearance
3. The opportunity of un-alerted
NOT see and therefore
NOT avoid is removed where pilot error is not a factor [incorrect report of altitude or position.
Indeed, there is no such thing as a SID or IAP that would not be "safer" with a higher minima, but that is not the way such design works. In fact, if you employed the same logic applied here to C over D versus E over D, there would be no low weather minima approaches, and probably no 200' CAT 1 ILS.
Wrong. For all the reasons explained above. SID’s and IAP’s are designed to be safe and as far as ‘reasonably’ possible [safe guards as listed above], error/failure tolerant. If you cannot see the difference between Instrument procedure design and safety monitoring when compared to the ‘normal’ mode failure opportunity of Class E, then I fear to say, you prove what many here are saying. You have no idea!
Whether you like it or not, CASA is bound to use a risk management approach across the board, witness the work being done by Aerosafe as a consultant to CASA, putting the meat on the bones of the basic policy of risk management.
Aerosafe, lets see:-
Aerosafe // Minimise Risk...Maximise Opportunity...
Nice web page, sounds impressive, lots of Helicopter companies involved in their subscription ASN, can’t see to many ANSP, National Aviation Regulators though.
Aerosafe // Industry Case Studies
AIR TRAFFIC CONTROL
Aerosafe has conducted risk culture analysis within one of the Force Element Groups of the Royal Australian Air Force (RAAF), which manages the Air Traffic Control functions. Aerosafe developed a cultural survey, which was completed by over 85% of the organisation. The results were analysed and presented back to the senior manager of that Group to use as a basis for the development of their risk management program.
A great idea.
In the meantime, an invitational to reinvent the ARM and CRFM will be one to watch. True enough, the ARM needs a GA only tool, oh dear, wouldn’t that have saved some red faces over the ‘intolerable’ FAA D/GAAP matter.
Any bravado that might be envisaged with mitigation such as ACAS will have to take into account the vast differences between ACAS performance between two track/trajectory predictable aircraft in proper CTA and that of only half the collision pair being ACAS aware and the other using startled GA eyes to try and avoid an ACAS manoeuvring RPT. There are a whole dinner party full of these little details being compiled by various groups. Suitors will have to be full bottle on industry acceptable thresholds as well as ICAO rule compliant.
Not to worry, the ‘meat on the bones’ will have to be served up to the industry, you know the ones who will have to rely on the RMS DNA before it is given a CofA.
We simply must adopt the best risk management standards in aviation, will we ever?? I don't know, but I have been pushing such adoption since well (years) before AS/NZ 4360 Issue 1 was even published.
Have you now changed tack since you realised AS/NZ 4360 is current risk management practice that could NEVER deliver Class E above D zones? It has been a variable and flukey set of wind changes from you these last 30 odd pages.
For those of you who want to have a bit of fun with the statistical term, "vanishingly small", it may be the equivalent of zero in maths, but "vanishingly small" is never "nil", or in other words, risk can never be nil, short of abolishing the activity.
Many thanks for stating the obvious to anyone with a cranium larger than a mouse. That is the very point contributors have been arguing, the risk of un-alerted not see and not avoid in Class E is not zero, it is also not vanishingly small when considering the concentration of climbing and descending aircraft in and around terminal area airspace.
If you decline to understand/accept that, it is no skin of my nose, but it does make the probability of your arguments being accepted ( in a technical, not political sense) , dare I say it, vanishingly small.
Of the pontificating and sermon giving, you fail to understand that well read risk managers in non-aviation expert fields, but inexperienced [in aviation and ATS] omit the risk multipliers. It was blatantly obvious in the three ‘bash bidjii’ papers since called in to question.
Your friend who likes to coin your often used ‘vanishingly small’ catch cry consistently makes the same miscalculation. i.e. collision probability in 100sq miles of en-route Class E [where few if any VFR aircraft are climbing or descending through other VFR and IFR] is statistically light years away from that of every aircraft IFR and un-known VFR climbing and descending through tracks converging in the 100sq miles of airspace above and around an airport or NAVAID.
You show me ONE, just ONE risk modelling tool that properly considers the large [comparatively] and very real difference in risk exposure of no structural vertical segregation [as all are aircraft climbing and descending around airports] and I will retire from this debate.
That you might succeed at a political level, by scaring the beejesus out of politicians, does not invalidate ICAO airspace design principles, it just proves how hard modernization of anything to do with aviation is in Australia.
Political operatives/minders [and the vast majority of pilots and air traffic controllers] reading this discussion will not buy that poor attempt to twist reality. ICAO airspace design is not the issue. The issue is properly assessing and allocating the correct airspace classification. You can keep trying to spin the reality, but you must know by now there are an endless supply of us ready to stop your merry-go-round in its tracks, day in, day out.
I have also said, time and again, that aviation regulatory reform in Australia (and that includes proper risk analysis) has been blunted and reversed time and again, by sectional pressure groups, with the results for all to see.
Another
Quotable quote