NAS rears its head again

[Frank Arouet]

As to how many such sports aviation aircraft there are around the country, I wouldn't have a clue.

Latest RAA magazine quotes 3077 aircraft at Feb 2010 and 10,136 members at Feb 10 2010.

I don't believe they are going to just go away. Probably best to factor them into the discussion.

[Capn Bloggs]

Leadsled,

The actions of the RPT Captains, in both cases, is worthy of close study and consideration

No it's not. Unless you are privy to something the ATSB hasn't put on the public record, there is nothing untoward in the actions of either RPT crew.

What is questionable is:

1/the decision by a "high time professional" GA crew (your words) to fly a high performance Lancair through busy terminal airspace VFR. That is just plain dumb, as the subsequent near-miss showed;

2/the insistence by you and Dick Smith that this situation was AOK.

I love the logic that says that RAs area serious safety problem in E, but can effectively be disregarded as a safety problem in C.

Put your reading glasses on. I said or implied nothing of the sort.

what we see here is the virtually automatic assumption the the GA aircraft is in the wrong, flown by somebody who doesn't know what they are on about.

Amply confirmed by the Tobago PIC.

For the newbies in this discussion, here are the links to the three Class E NMAC reports:

737 v Lancair Brisbane

737 v C421 Canty

Tobago v 737 Launy

Arr, the virtues of E airspace.

[ARFOR]

Lets bore the audience with some history and clarity:-

If you believe the Airservices "risk analysis" for the windback of 2B was kosher, you obviously haven't read the three analysis by eminent risk management experts, including one paid for by CASA. Or maybe you really believe the error rate for pilots dealing with ATC instructions really is 50 to 100%, but for ATC person, only one in a million.

If one were to accept what you say as being the case, and apply a correction factor, the net effect [difference in outcome] of the collision modelling [ARM] [and ALARP] would amount to an amplitude difference of how much? I would suggest ‘nil’ in terms of scaled collision mitigation options that are available, particularly where surveillance is not available to offset the lack of an Air Traffic Control Service to both IFR [on conflicting but unknown VFR] and other conflicting VFR with VFR in Class E!

Whilst we are at it, we need to clarify the use of the word ‘analysis’. In the context of these ‘safety’ related discussions, the two main groupings within the ‘defined’ aviation processes are ‘HazID’, and of course separately ‘Aeronautical Studies’.

HazID’s

I have seen some of those for NAS2b, and know some of those directly involved. The HazID’s did not support the retention of a specific class of airspace above class D zones, rather, identified the hazards that needed mitigation. We should discuss how these were then applied [or not] to the non-existent volume specific assessments and ALARP? Which of course brings us on to the ‘governance’ trigger for the return to class C?

Mr Jeff Griffith [whom I have met] from the US, was first involved in Airspace in Australia in 1996, through 2004 [NAS2b]. In 1996, he was contracted by the then Australian NAS Implementation Group to provide technical input into each of the NAS characteristics. Previous to NAS2b commencement, industry raised concerns regarding the lack of volume specific safety assessments. None the less, NAS2b went ahead.
After several safety issues, and subsequent BASI/ATSB reports, moves were made by industry to address the inherent inadequacy of Australian NAS2b Class E.

The reports you mention

In 2004, Mr Griffith was again called on this time by CASA to assess the Airservices case for return to Class C over D. In August of 2004 Mr Griffith submitted the following:-

http://www.infrastructure.gov.au/avi...ith_Report.pdf

- He suggests that the US NAS is safe and efficient [see the NTSB data below]
- He makes no mention of the difference between Australia and the US in terms of surveillance, ATC sector size, traffic density comparisons.
- He makes no mention of the disparity between US D/E and Australian D/C Air Carrier movements.
- He seems unaware [or omits] that the US NAS operates Class C where similar levels of RPT/Air Carrier aircraft operate in Australia.

It was put to Mr Griffith at the time, that the absence of commonality between the two systems made transplanting one into the other necessitous of volume specific safety cases, which before rollout, had been rejected by the NAS people he had been working with.

In addition to the Griffith report commissioned by Mr Dolan at CASA, was of course Professor Terry O’Neill’s report, whom CASA also retained to assess the Airservices safety case for return to class C

http://www.infrastructure.gov.au/avi...AAs_NAS_2b.pdf

With regard to method, Professor O’Neill said:-

The other approach is to recognize that there is a wealth of relevant data available in other countries, for example the United States. Nevertheless there is considerable disagreement about whether the use of this data would be appropriate [8].

[8] It is noted that in previous modelling exercises, the accuracy of the ARM was tested when its risk profiles were compared with risk levels predicted by the US FAA’s collision probability formulae for uncontrolled and controlled non radar terminal areas – the formula used in air traffic control tower cost-benefit reviews in the US, Canada, Australia and New Zealand.

Here are some other extracts relevant to our discussion:-

The argument revolves around the comparability of the two countries. For example, Airservices argues that a comparison with the US is not appropriate due to differences in weather, topography, pilot behavior and culture and ATC systems. Some of these factors may increase while others may lower the rate of collisions. The following two points can be made about this controversy:
• It may be possible to estimate and formally characterize the size of any such differences and control for them statistically in the modeling process
• No two situations will ever be exactly similar. What is important is the relative importance of these differences compared with the size of the effect being estimated. The larger the apparent effects noted, the more confidence there would be that these were not entirely due to extraneous factors.

Correct. Which in hindsight is exactly why industry at the time were vigorously asking for volume specific assessments prior to the NAS2b roll out. They did not happen.

He goes on to say:-

Reasonable agreement of the model with the US data would be reassuring. On the other hand, dramatic differences would suggest that all is not well with the modeling exercise. The comparison would need to allow for the differences, but the differences should not prevent the comparison being made.

Again correct. Why was it not done?

Alternatively, rather than checking the Australian estimated risks against the United States, the whole modeling process could be tested directly on United States system. United States traffic data from comparable locations could be fed into the TAAM software and a United States expert panel could be convened to populate a fault tree with probabilities. If this exercise produced estimated risks in reasonable agreement with observed empirical risks in the United States, then it would supportive of the modeling exercise in Australia.

An expert panel from the US? great idea! Why was it not done before roll out?
Does any of this sound familiar?

It strikes me as foolhardy to remake similar errors of process.

"Low" and "vanishingly small" are far from the same thing.

The difference of course is that ‘low’ is part of the scaled outcome terms used when reporting considered risk/s. Where does ‘vanishingly small’ feature in defined aviation [airspace] risk assessment processes?

On that theme:-

Several Airservices "analysis" of US MAC/NMAC in E have been "interesting", one neglected the fact that much of the mid west is 6/7000 ft, and claims a number of en-route problems. When the geographical position and height was examined, it was clear that ALL to alleged en-route MAC/NMAC were, in fact, in circuit areas or the boundaries of circuit areas, they might have been 7/8000' AMSL, but they were only 1000/1500' AGL.

The class of airspace involved with these MAC and NMAC’s was? Remembering of course the practical differences between US D rules and ICAO D application such as Australia and the UK! Or were they plain old Class E accidents and incidents?

Have you a reference?

From the Broome ’Aeronautical study’, may 09’

In addition it must be stated that the ARM equates MBZs to CTAF(R) procedures and assumes that pilots are 99% procedurally compliant.

Clearly the ARM does not equate the error rate for pilots dealing with ATC instructions to be 50 to 100%. I’m not sure the Airservices case [2004 rollback] using TAAM came to that conclusion either.

And;

5. Modelling
The OAR used the Airspace Risk Model (ARM) to model the airspace affecting the Broome aerodrome. The Airspace Risk Model (ARM) and an F(N) curve was developed by the Civil Aviation Safety Authority (CASA) and utilised by the OAR.
CASA has developed ‘acceptable risk criteria’ with regard to the risk of midair conflicts within regional aerodrome terminal areas. The collision risk model developed by CASA, in 1996, is focused on a non-radar controlled terminal area model and no significant changes have been made since its development and presentation to the Review of the General Concept of Separation Panel (RGCSP), now the Separation and Airspace Safety Panel, of the International Civil Aviation Organization (ICAO).

This aviation risk assessment tool is internationally recognised, and has been used for many years. Funny thing though, where is the modelling calculations for the options within the Broome report, including the E over D, and C over D options?

Sound familiar?

In general terms regarding risk in class E:-

Aviation Accident Database Query There is plenty in there to sober up with!

More specifically, Class E, and the limitations of see-and avoid, I commend the following TSB Canada report to the interested reader:-

http://www.tsb.gc.ca/eng/rapports-re...6/a06o0206.pdf

The collision occurred in Class E airspace (see Appendix A) where there is no requirement for an air traffic control (ATC) clearance or radio contact with air traffic services. In this type of airspace, there is no requirement for position reports, traffic advisory calls, or for aircraft to be on a common very high frequency (VHF) radio frequency. Aircraft are not required to have a communication radio, a radar transponder, or collision-avoidance equipment on board. It is unlikely that there was any communication between the two aircraft.

There is considerable guidance and research material on this subject (see Appendix F for endnotes), salient aspects of which are as follows:
• Conspicuity characteristics
- Specific paint schemes and patterns may have an advantage in certain conditions but none has an overall advantage over another.
- Anti-collision/strobe lights do not have a significant effect in bright daylight.
- Landing lights are useful when the opposing aeroplane is in the direct beam.
• Pilot scanning technique
- The United States Federal Aviation Administration (FAA) recommends that pilots spend 75 per cent of the time scanning a 180° by 30° field of view outside the cockpit.
- Estimates vary from 54 seconds to 9 minutes to perform the scan.
- A total of 12.5 seconds is required after first detection for pilot recognition and reaction to avert a collision.
- In practice, pilots spend 33 per cent of the time scanning outside mainly within 10° of the direction of flight.
• Effect of traffic alerting
- Proportion of time spent scanning outside the cockpit tends to increase.
- Attention is focussed on known location of conflict.
- Probability and range of detection increase.
• Probability of detection for this collision geometry and closure rate
- Maximum discernable range for 6/6 visual acuity: 8.5 km.
- Earliest likely detection range and time: 3.2 km, 28 seconds.
- Probability of detection for 33 per cent outside scan time: 25 per cent.

TSB records indicate that 16 mid-air collisions occurred in Canada during the preceding 10-year period resulting in 27 fatalities and 5 serious injuries. Of these accidents, 4 involved some form of formation flight or gliders operating in thermals, and the remainder involved aircraft that were not associated with each other. None were within Class D or higher airspace, and none occurred under ATC or advisory service. A total of 6 accidents occurred within the traffic zone of an uncontrolled airport and 6 involved flight beneath controlled airspace associated with a major airport. One of these occurrences led to a Transport Canada safety review in 2001-2002 of VFR operations in the vicinity of Toronto, Ontario,1 significant aspects of which are as follows:
• Routing restrictions and confined vertical dimensions contribute to traffic congestion.
• Two system deficiencies were identified concerning availability and quality of aeronautical information and lack of standard operating procedures for VFR operations.

This is what concerns me [and apparently many others] with Class E and not properly utilising/applying A.L.A.R.P :-

• A number of risk scenarios were identified in which a mid-air collision was a potential outcome that was considered unlikely within the five-year time horizon of the study.

Yet ‘vanishingly small’ came home to roost!

• Several recommendations were made to address the deficiencies and risks.

There has been little progress in implementing the recommendations.

Another of the occurrences took place approximately 5 miles west of the location of this accident and in similar weather conditions. It involved a Cessna 172 aeroplane on an instructional flight and an ultralight aeroplane on a pleasure flight. The right main wheel of the Cessna 172 rolled along the top surface of the left wing of the ultralight. The ultralight was damaged but was able to land safely. The Cessna 172 was undamaged. Neither aeroplane saw the other before the collision.

Make that came home to roost twice!

A number of international studies (see Appendix F) have addressed the overall issue of risk of collision and effectiveness of the see-and-avoid principle. All acknowledged the underlying physiological limitations at play and that, when mid-air collisions occur, “failure to see-and-avoid is due almost entirely to the failure to see.”

One study stated that “our data suggest that the relatively low (though unacceptable) rate of mid-air collisions in general aviation aircraft not equipped with TCAS is as much a function of the ‘big sky’ as it is of effective visual scanning.” Specific results relevant to this occurrence are as follows:
• A French study of mid-air collisions in a 10-year period found that the see-and-avoid principle was becoming no longer adequate as the sole means of averting collisions.
• An Australian study concluded that the see-and-avoid principle, in the absence of traffic alerts, has serious limitations and that the historically small number of mid-air collisions is as much due to low traffic density and chance as it is to the successful operation of see-and-avoid. The most effective response to the many flaws of see-and-avoid is to minimize the reliance on it.
• A German study on the detection of gliders and small motorized aircraft found that passive conspicuity measures did not overcome the underlying limitations of the see-and-avoid principle. It recommended further development and promotion of GNSS and Mode S transponder technology, noting that there is already on the market a GNSS–based system that is ADS-B compatible, called FLARM. That system is in use on gliders and provides collision-avoidance information.
• Eurocontrol examined risk of collision scenarios between uncontrolled VFR general aviation aircraft and both other uncontrolled VFR traffic and IFR commercial air traffic and found that see-and-avoid was ineffective as the sole means of averting collisions. It preferred technological solutions, specifically increased use of Mode S transponders to function with secondary surveillance radars (SSRs), aircraft collision-avoidance systems (ACAS)/TCAS, TIS, and ADS-B, and to that end endorsed continued development of the Light Aviation SSR Transponder (LAST) including low-powered variants. It found that systems such as FLARM could reduce the risk of collision between VFR aircraft.
• A British Royal Air Force study into mid-air collisions deemed to be random found that the probability of conflict is proportional to the square of the traffic density and recommended avoiding altitude restrictions that concentrate traffic.

Common theme!

Analysis
There was no indication that crew performance played a role in this accident or that either aeroplane was ill-equipped as to conspicuity devices or that those devices were not used appropriately. A realistic probability of either aeroplane detecting the other was 25 per cent, and without detection, the collision was unavoidable. The two aeroplanes were on a constant collision course; therefore, there was no relative angular movement that could be detected by peripheral vision to aid in detection. There was no other means of alerting either aeroplane as to the presence of the other. ATC does not provide traffic advisories in that airspace.

This about sums it up for me:-

Measures such as improving aircraft conspicuity, pilot scanning technique, and pilot traffic awareness can reduce risk, but they do not overcome the underlying physiological limitations that create the residual risk associated with unalerted see-and-avoid. There is only limited potential to further reduce risk by fine-tuning the unalerted see-and-avoid concept, and such an approach does little to address the risk of collision between VFR light aircraft and IFR commercial traffic in congested areas.
A meaningful improvement to the ability to see-and-avoid between uncontrolled VFR aircraft requires a practicable, affordable method of alerting pilots to the proximity of conflicting traffic. Reduction of conflicts between VFR aircraft and IFR traffic depends on making aircraft that are presently not transponder-equipped visible to ATC or to the IFR traffic.

Learn from others who know from bitter experience, the bitter experience is world-wide!

[Howabout]

Lead, you remain a gentleman and debate on merit. Unfortunately, not everyone does.

As regards your point on TCAS II; sorry, but it just doesn't wash. You have been most vociferous about not registering differences. All of a sudden you maintain that such a course is OK. Once again, you can't have it both ways old sport.

NAS was plagued by cherry-picking. TCAS is the last line of defence, as recognised by ICAO, and should never be used as mitigation in the classification of airspace..period.

Dick, I'm still waiting for that controller out of the 'dozens and dozens' that has put his/her real name to the assertion that E is cheaper than C.

Surely they would use their real name on something so important.

I am sure you will agree.

Lead, you're on the wrong sled. Unfortunately, for you, your genuine attempts to inject objectivity are destroyed by infantile obfuscation from a direction that's sometimes referred to as 'friendly fire.'

[Capn Bloggs]

An interesting post, ARFOR. Thank you.

A meaningful improvement to the ability to see-and-avoid between uncontrolled VFR aircraft requires a practicable, affordable method of alerting pilots to the proximity of conflicting traffic.

Get them to call ATC for a clearance...in C airspace. It doesn't cost anyone a cent.

[Howabout]

Holy Ghost ARFOR, is that copyright?

I'd like to print and frame.

OK, where's the ATC that is so passionately committed and is one of Dick's 'dozens and dozens' that will tell us under his/her real name that E is cheaper than C.

After all, Dick asserts that if you are unwilling to use your real name then you don't have the courage of your convictions.

Guys like ARFOR, DNS, the penguin, and a host of others, can be shot down by only one of those 'dozens' posting under their real name.

It's simple: All you have to say is that 'E is cheaper than C and my real name is (for example, something like) Dick Smythe'

How hard is that in the interests of credibility??

[Jabawocky]

Going to play devils advocate here.... IF and I say IF we had the 100% ADSB fitment, E over D in the regional areas, with the local ADSB feeds to ATC and ADSBin/TCAS for RPT or anyone who wanted it, how would that stand up?

At least the IFR heavy metal would have a chance against any VFR's who may be out of the system and bending the rules (yes there are lots that do, the reason Bloggs and co are concerned) when lots of IMC is around the approach to regional airports.

That would beat class G any day, and be better all round for all concerned I think.

Only problem I see is the other side of the fence debated against the proposed scheme. Could have helped their cause I reckon.

Over to you pro folk to debate if you think its relevant. (If not ignore and back to normal viewing)

J

[Howabout]

Jab, with all due respect, don't put yourself down. You are perfectly entitled to throw in your thoughts.

I'm no expert when it comes to ADS-B, but I think that as a solution it's a long way off.

The immediate question is 'what can we do with what we have?'

From my perspective, and in light of the deafening silence from the 'dozens,' if a Class C service can be provided, with no extra resource implications, then it should be.

Anything less, with fare-paying, trusting punters down the back is culpable negligence.

God help the poor sod that sticks his moniker on a piece of paper that says E when C could be done for the same price.

In the event of a prang there'll be nowhere to hide.

[Jabawocky]

Howabout

Thanks, just food for thought given those that want the greater freedom of E for VFR, yet seemed to put arguments against a proposal that would have made there current agenda more warm and fuzzy. Some of them were not ANTI ADSB as such, but argued against its 100% scheme and as such have denied a way of achieving their current ideals while at the same time satisfying the ............

Anything less, with fare-paying, trusting punters down the back is culpable negligence.

In my mind in the remote places, especially when the wx has been like it has of late over the interior E over CTAF's and E down to very low levels like in the USA would be a better thing than IFR bashing around in G with no service at all (Mt Isa for example). In good weather well its pretty much the same as G for both IFR and VFR really, but in bad wweather it should help the IFR.

For the busier terminal areas (Launie, Alice, Maroochy etc) C over D actually makes sense for the climb / descent zones, and E elsewhere, say around Hervy Bay Bundy, Ballina etc.

From what I can see E in place of G would be a good thing when weather is a problem. But without Radar maybe the RPT folk would rather self seperate until up into C. I will leave that to the pro's to comment on. Mind you the other day all in class G we had a Rex, a Virgin and a Jaba all in IMC plus a meat bomber (assume in VMC) and Class G, BNE CEN was working hard at keeping all informed but it would have been nice to have had the one bloke who could see all of us at once to do the seperating rather than all of us trying to get it right. We almost had E in G there .....minus the official seperation. Now the cost of that must have been the same as G=E=C....

Anyway......back to my fencepost.

[OZBUSDRIVER]

Jaba...your on the money wrt ADS-B Rx, one piece of kit changes the entire outcome of NAS airspace issues.

ARFOR, that is a top post. You have distilled years of argument wrt the fallacy of UNALERTEDSee and Avoid, and the folly of cherry picking the US system without also the facilities and procedures accorded to movement levels as well as all the links to relevant articles.

Leadsled, mea culpa

[Mike Barry]

One of the many...

Quote:
When are you going to get it into your head that ATCs say there is no extra workload running C as opposed to E?
Okay Capn Bloggs, I issue you a challenge. Get ONE practising ATC to state this point under his or her own name.

Ok Dick, I'll bite...there is no extra workload running C as opposed to E.
There is also no extra workload from A to C...
Happy now?

You can quote me if you like.
For the record...ex FSO multiple stations, ATC in Perth, Brisbane, Muscat, Abu Dhabi and Shannon.

[CaptainMidnight]

ARFOR - great post ......... thank you.

Jaba - re 100% ADS-B fitement. I don't know to what extent the ABIT proposal went to fitting the sports aviation fleet e.g. to hang-gliders. They might have been included. You would also have to have ADS-B in gear fitted to powered aircraft so they can see the traffic of course.

FWIW one H/G pilot told me he regularly operates in NE Victoria up to A100, and that he has on occasions had powered aircraft pass underneath him. I suspect those aircraft never sighted him. You wouldn't intentionally fly under a H/G - you'd give one a wide berth.

[Frank Arouet]

the captain of the fairies is loose in the bottom the midnight garden.

Who can forget the ABIT (ADSB Implementation Team) and all their broken promises and lies!

Credibility about the same as a "rock spider's" court testimony having been caught at a "Wiggles" concert.

BTW, was it a hang glider thermalling up to 10,000 feet or a powered trike.

You wouldn't intentionally fly under a H/G

Someone should throw a net over you.

[CaptainMidnight]

Frank

Sorry, none of your post makes any sense to me.

I was not offerring support for the ABIT or otherwise, merely stating I wasn't sure if the proposed fitment covered all SPA types.

And hang gliders in NE Vic operate up to 10,000 feet (A100) not 1000 feet (your A010) - that make any more sense to you?

[Frank Arouet]

There you go Captain. (Another pedant), I have amended my last post. (But why then would you think anybody is so blind as to fly under a hang glider when it was at 1,000 feet)?

As for ABIT. It was a gathering of fairies with magical promises that anybody could be excused from knowing what was proposed and what wasn't. It was a sham by confidence tricksters and a disgraceful waste of money.

You would also have to have ADS-B in gear fitted to powered aircraft so they can see the traffic of course

Really?

I asked whether it was a hang glider or a powered trike for a reason. I take it this would have been in class E airspace?

[Dick Smith]

Mike, are you refering to class C over D at place like Broome with no terminal radar?

Let's say there is a VFR aircraft at 6500' going from south to north about 20 miles to the east of Broome at the closest point. At about the same time you have an IFR Kingair on descent from the east, inbound to Broome as well as local flights and circuit traffic. It's sky clear.

Do you still believe that there would be no extra workload for the controller at Broome if C was allocated rather than E?

Pull my other leg!

[LeadSled]

Howabout,

You have been most vociferous about not registering differences

I have no idea where you got this idea.

On the contrary, in several formal appointments in the past, I pushed hard for Australia to clean up its act in notifying differences to ICAO --- an area where Australia had been very slack, with some quite serious consequences, particularly NMACs, brought about by differences between Australia and ICAO ATC terminology.

At least all those terminologies have been harmonized now, but Australia's (or at least, some Australian pilots) determination to be an aviation Galapagos, with all sorts or wild and wonderful mutations of aviation developing in splendid isolation, seems to be as strong as ever.

Unfortunately, a predictable result was the Australia section in the Jepp. WW Text becoming as big as it, sadly, is.

I see we have a new term invented by the naysayers:

Unassisted See and Avoid,

However, many of the posts here refer to "un-alerted see and avoid", and nobody has seriously advocated "un-alerted" see and avoid, quite the contrary, as I have pointed out in writing, on many occasions.

Nevertheless, all the usual suspects trot out "un-alerted see and avoid" right on que as a straw man to shoot down!!Bbut wait, there's more, now we have something new

--- Unassisted see and avoid.

Back to the NAS 2b windback, anybody who believes a 1 in 1 to a 2 in 1 error rate for pilots executing ATC instructions is a reasonable error rate must have two willies, you can't get that stupid playing with one. Just as much as ascribing an error rate of (by remarkable contrast) 1 in 1,000,000 to ATC persons.**

To further suggest that such figures do not materially alter the outcome of the analysis is (at best) revealing the writer has no in-depth knowledge of the various qualitative and quantitative methods of risk assessment.

As usual, we have some wonderful examples of selective quoting, on the entirely reasonable assumption that most readers will not bother to read the whole of a very lengthy document.

However, to suggest that Prof.O'Neill's report on the NAS 2b windback supports the process is taking self delusion to a new high. On any reasonable reading of the O'Neill report for CASA, or the reports done by three other highly qualified persons, can only be described as scathing of the analysis, including such ridiculous "data" as the above mentioned error rates for pilots and ATC.

IF Australia had an outstanding safety record (using ICAO standard terms, not selective reporting) there might be some logic in rejecting the US approach, but as US/FAA has better safety outcomes in all categories except gliders, I see no reason to not learn from the US. This is comparing US with everybody else, not just Australia.

Indeed, even in the narrow area of actual collisions (again excluding gliders) the Australian record is inferior to the US, as anybody can see by an examination of published figures.

Tootle pip!!

PS: The excellent safety record for gliders in AU, (and almost as good in UK) is quite reasonably ascribed to the quality of community administration of gliding by GFA. This is the one single area of air safety outcomes where we are head and shoulders above the US.

** Maybe this is reflective of true level of respect many controllers have for pilots, a suggestion not entirely without "foundation". In about 2002/3 or thereabouts, the Flight Safety Foundation did a most interesting study of Australian pilots, ATC persons and maintenance engineers, and their attitude to each groups contribution to Australian air safety.
Go look for it on the net, and read it, in summary, each group regarded their contribution to air safety as the most valuable, and the other two groups as threats to air safety. A psychological analysis of the individual and group answers was fascinating.

[OZBUSDRIVER]

Leadsled...post changed..100 times UNALERTED..UNALERTED..UNALERTED..UNALERTED:ug h:
unassisted, I can make the most monumentaly epic fails......regardless!

[Freedom7]

Let's say there is a VFR aircraft at 6500' going from south to north about 20 miles to the east of Broome at the closest point. At about the same time you have an IFR Kingair on descent from the east, inbound to Broome as well as local flights and circuit traffic. It's sky clear.

Do you still believe that there would be no extra workload for the controller at Broome if C was allocated rather than E?

Give me the exact senario, ie you make it up, and ill give the action response for both classes of airspace.

I dare you

[Howabout]

Leady, I'll take a hit. In retrospect, my post was ambiguous. My point was that in the interests of 'uniformity' you believe that we should not be in a position where we have to lodge differences or, at the very least, the differences should be minimal.

I also accept that your position has been one of stating that where differences exist they should be lodged. What I said was clearly ambiguous.

The thrust of the post was that, on the one hand, you appear to support the use of TCAS for airspace allocation, provided a difference is lodged; yet on the other, this appears to be at variance with your belief in 'uniformity' and avoiding differences.

That was my point regarding the apparent inconsistencies in your argument.

Regardless, this debate is really about the provision of an 'inferior' service, when a 'superior' service can be provided for the same resource expenditure. Once again, it goes to the 'negligence' argument. Why in hell would one commit to an airspace construct that can have unknown VFR, when the alternative of positive separation for the fare-paying punters is available for the same cost?

That's where I cannot understand, or accept, the logic behind E over D. For my money it should be all C, given that the controllers themselves have consistently stated that they can provide positive separation at no extra cost and a lot less grief.

It just doesn't make sense Lead.

Thank you Mr Barry. Nice list of credentials. Hope you are enjoying my west-coast ancestral home, although we come from a bit north (Galway/Castlebar). Great pubs!

Lead, in the interests of keeping it civil, thanks for the reminder about Rose Bay. My old man, before we went north with AWA (1964), used to regularly visit the Sunderlands down that neck of the woods to sort out the 'snags' - that was always his term.

He had a couple of flights to Lord Howe, compliments of the crew, after sorting out a few particularly difficult problems. Nice: In those days it was 'Thanks, come for a ride. We'll tell the company that the snag was so bloody repetitive and difficult that we wanted the tech expertise along in case there was a repeat.'

Dick, I'm still waiting for that one controller to post under his/her real name and state, unequivocally, that E is cheaper that C.

After all, how difficult can it be if 'dozens and dozens' have told you that E can be done easier (cheaper) than C? If one of the 'dozens and dozens' really does believe that E is cheaper than C, then they must be willing to post under their real name. If they have told you that E is cheaper than C, and can substantiate it, then why would they be afraid to post under their real name?

Hasn't that has been one of your consistent points?

The phrase 'I am sure you will agree' comes to mind.

Just one Dick! One out of the 'dozens and dozens!' Just one!