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-   -   NAS Frequency Boundaries continued. (https://www.pprune.org/australia-new-zealand-pacific/108092-nas-frequency-boundaries-continued.html)

tobzalp 12th Nov 2003 08:04

Seems a bit late for that now. Don't tell me you all agreed without really thinking about it in the first place?!

Four Seven Eleven 12th Nov 2003 08:11

Lodown, ftrplt et al

I havent seen the new charts yet, has anyone looked at the steps to see if there is an issue for RPT on descent into airports where Class A overlies Class C? (i.e 747 descents into Sydney etc). Is it going to only be an issue for descent into Class D 'Airspaced' airports?
Yes, it most certainly is an issue for jets into Sydney. Class E will be outside 45NM, down to 8,500ft – ensuring that B747s etc. will have to fly in E when arriving at Sydney. In some configurations, aircraft are required to be at 10,000ft by 45NM, so staying up at FL190 to 45NM is not even a theoretical option, never mind a practical one.

Class D towers often have the additional risk of little or no radar coverage.


4711, doesn't TAAATS provide a level of protection by alerting controllers to conflicting traffic in conjunction with transponder-equipped aircraft and SSR? Obviously you wouldn't want to use this as a last line of defense, but this is something, like TCAS and GPS that we didn't have some years ago.
Yes, TAAATS does have a STCA function. As has been mentioned elsewhere, it is not 100% reliable for real conflicts (often giving its first alert after the aircraft have passed) - quite apart from the already significant problem of ‘false’ alerts. The new procedures (as well as older methods of reduced separation such as visual separation etc.) will lead to an increasing number of these false, ‘desensitizing’ alerts.

GPS, paradoxically, increases the risk of a collision, as its very accuracy ensures that two aircraft which are on reciprocal tracks will be right on track. In the ‘old days’, NDB VOR or dead reckoning errors would increase the likelihood that aircraft would miss each other, even when they were one the same ‘nominal’ track.


Whatever it was, I know I'd put my trust in modern technology over the system we had then. Taken in isolation, each one of these technologies would not be trusted as a 'last line of defense' but when the entire system is considered, then I don't have a problem with this aspect of NAS.
I concur most heartily. Perhaps our difference on emphasis is that I would prefer to see our current system enhanced by new technology, rather than replaced by it, especially when the equipment was designed as a fall-back, rather than as a primary system of defence.


I am still in two minds about NAS, but surely if the technology allows us to advance and make the airspace more user friendly for all while raising capacity and at the same time without impinging on the operations of the big boys, then I am all for it.
Two minds are always better than none at all. I am yet to be convinced that the current system is as user ‘unfriendly’ as it is made out to be. Unfortunately, introduction of E, both inside and outside radar coverage does impinge on the ‘big boys’. It reduces their current level of safety.

Consider the following scenario:

A Boeing 737 on descent, with a ground speed of 450KT and a rate of descent of 2,500fpm. The weather is overcast at 13,000FT, VMC below. It is night time.

Ahead of the 737 is a light twin, maintaining FL125 (VFR) with a ground speed of 150KT.

The 737 breaks out of cloud at FL130, and has 12 seconds (500ft at 2,500 fpm ROD) to see the lights of the twin against the lights of the town below, identify it as an aircraft, identify it as a collision risk, and either arrest the rate of descent or take lateral avoiding action. The distance between the aircraft at first visual contact opportunity would be one mile (300KTS closing speed for 12 seconds)

The light twin, not being equipped with rear view mirrors, never has an opportunity to see the 737 at all.

Yes, this is a ‘worst case’ type scenario, but most accidents tend to be. I ask you to consider whether this is the basis for a safe system.

The current option is for the VFR aircraft to be known to the ‘system’ and the aircraft to be separated.

Aussie Andy
Lest any of our more 'sensitive' characters draw any unwarranted inferences from the refence to the timing of NAS vs the next election, the only implication is that NAS is supported by the current minister and is opposed by the ALP. Thus, it would need to be impelemented before the election in case the coalition was voted out.

ftrplt 12th Nov 2003 08:47

Genuine question, just how many VFR's are there above 10 000ft, let alone above 7 to 8000ft???

Shitsu-Tonka 12th Nov 2003 08:52

AK: With all the respect I can muster for the remains of AOPA I have to still ask why are you formulating a policy position on NAS at what is once again the 11th hour? Especially as AOPA have been involved in preparing the education package for heaven knows how long?

Converesly the professional associations have been trying to get responses to specific technical concerns for a long time - the issues were identified long ago. But they were dismissed as 'unions protecting jobs', and scaremongering. This was always rejected as pro-NAS rhetoric.

I am glad you now see it was and is not.

And that the latent failures in this system are now apparent to all , except the minister - publically at least.

Now we just await the inevitable public realisation - once again at the 11th hour - any bets on dates? The 11/11 has passed after all!

Four Seven Eleven 12th Nov 2003 09:14

ftrplt

Genuine question, just how many VFR's are there above 10 000ft, let alone above 7 to 8000ft???
Probably not many. This does raise a few points:
1) The real danger is going to be when the jets are at and around 10-9,000FT and descending through the VFR maintaining 9,5000FT
2) Due to costs, what proportion of Metros etc. will be ‘encouraged’ to fly VFR through E (above 10,000FT) to save on charges?
3) It only takes one mid-air collision to ruin your day.
4) If the answer to your question is in fact ‘so few that the system is perfectly safe’ – then it begs the question – “why bother, if the benefit is there for so few aircraft?”

By the way, over Class D towers, Class E will extend to 4,500FT.

snarek 12th Nov 2003 10:22

plazbot

Because we have seen some charts (although I ask as hard as I can I don't get any).

I am not sure whether to blame incompetence or conspiracy, but either way NASIG have relied on AOPA support without providing the material to the Board to earn or reinforce that support.

But, like I said, we will fly the maps and make our views known.

My first personal view, why no approach freqs???

Do I call Tower and get told call approach??? (unnecessary chatter).

I am interested in other AOPA member views on the charts as they become available.

AK

Aussie Andy 12th Nov 2003 14:34

G'day 4-7-11,

...ensuring that B747s etc. will have to fly in E when arriving at Sydney...
Not very different to a B747 etc. from LHR on descent to Newark NJ southbound from Albany NY through Class E really. Again, I just think that to have the debate in isolation of practices and outcomes elsewhere when the whole idea is to implement practices common elsewhere weakens your argument.

The example you give of a GA VFR a/c 500' below cloud might be a little bit misleading also as one should maintain 1000' from the cloudbase ideally - but the point is still taken (yes, 24 seconds is not much better than 12 seconds! :uhoh: ) and anyway given datum errors or poor airmanship etc. (scud-running, moi!?), then I see the point. In the US they simply indicate approach and descent paths (with a little light-blue jet on the chart) that you are "recommended" to avoid. Doesn't sound great does it, but the outcomes appear to be OK: and that's the point.

Re- ALP, well (as a long standing member of both the ALP and subsequently the British Labour Party now that I live here) I casn only say that when in opposition, one opposes!

Andy ;)

Blastoid 12th Nov 2003 16:45

Don't forget those holding patterns in E e.g. North of Brisbane (SMOKA, MLY). But VFR should know to keep clear of them anyway, right? :yuk:

triadic 12th Nov 2003 19:53

When do we see the rest of the education and training ???

Huh!

C182 Drover 13th Nov 2003 04:04

Speak to AOPA as they have it all under control. Check their forum http://www.aopa.com.au/forum/phpBB2/ or ask snarek. :ok:

Icarus2001 13th Nov 2003 04:22

I received the two volume package that most pilots seem to have received, containing the reference guide and the in-flight guide but I heard on the grapevine that there was an Instructor Pack.

So I searched the website but could see no reference to an Instructor Pack. I rang the "hotline" and the lady who answered could not help me as she had not heard of an Instructor Pack either and to my surprise arranged to get someone to call me the next afternoon!

Two days later I had not heard so I called again. Eventually I arranged to have one delivered.

Are other instructors getting them automatically?
Are flight schools getting them automatically?
How come the "hotline" staff do not know anything about them?
Why did I have to wait over 24 hours for a response?

Chimbu chuckles 13th Nov 2003 05:10

2001...you're not suggesting Hot mike was less than candid with the minister when he suggested there existed an instructor pack are you:uhoh:

Seems like nothing he said in hansard was accurate:suspect:

Chuck.

Four Seven Eleven 13th Nov 2003 05:15

Aussie Andy
Indeed you are correct. The VFR aircraft would need to be 1000FT vertically from cloud, giving the jet a theoretical 24 seconds to react. Having just checked on the VMC minima in E, however, an even more frightening ‘worst case’ scenario arises.

The VFR aircraft is required to be 1,500M horizontally from cloud. This gives our unfortunate jet driver potentially less than one NM or say 10seconds to see, identify and react to the conflict.

Either way, I am not just trying to score points by finding ever worsening scenarios. What I am saying is that the system needs many tiers of defence, because, however remote or otherwise the odds of a collision are, the consequences of a single accident are horrific.

You also said:

Again, I just think that to have the debate in isolation of practices and outcomes elsewhere when the whole idea is to implement practices common elsewhere weakens your argument.
I agree that international harmonisation is an important issue in aviation. It should be remembered that Australia is very often at the leading edge of changes to procedures. For instance, Australia introduced RVSM (Reduced Vertical Separation Minima) some years ago, whilst the US is planning on implementing this significant change some time in the next two years.

No-one is suggesting that we should regress to the current US system of vertical separation. Rather, we wait for the US to catch up with Australia, many Asian countries and Europe.

Other examples of Australia leading the way are RNAV separation, ‘automated’ ATC systems (TAAATS) etc. My point is that following the US system is not necessarily always progress. Some studies in the US have suggested that the system there needs to made safer by including the VFR into the system.

Edited to correct some dodgy mathematics

Lodown 13th Nov 2003 06:04

So much for all those 'safety' features on TAAATS. Reminds me of the cartoon (Dilbert, I think) where one of the characters was talking about all the worrisome bugs in a new planned software release. Another character commented to go ahead with the release and call them 'features'.

4711, can't the same situation regarding VFR aircraft at upper altitudes mixing with 737s occur now? It comes back to having figures which support a thorough safety analysis.

Icarus2001 13th Nov 2003 06:09


Again, I just think that to have the debate in isolation of practices and outcomes elsewhere when the whole idea is to implement practices common elsewhere weakens your argument.
To implement practices used elsewhere in an environment with differing infrastructure is not implementing "the proven US model".

Do they have greater radar coverage in the US? Yes

Do they have briefing offices? Yes

Do they pay for charts etc in the Us?

Back to first principles, we have assertions that NAS will lead to significant savings. Mr R Smith used a figure of $70 million. Now we see in Senate commitees that there may even be a cost, from less service.

So where is the motivation for the changes?

Four Seven Eleven 13th Nov 2003 08:34

Lodown


4711, can't the same situation regarding VFR aircraft at upper altitudes mixing with 737s occur now? It comes back to having figures which support a thorough safety analysis.
No - at least not into any controlled aerodrome. At jet levels it is currently all Class A, C or D, which means that IFR get fully separated from evryone. VFRs need a clearance to be there.

The only way a jet could be in that situation now would be in the lower traffic/lower risk areas where they descend from C, perhaps through E into G.

In NAS 2B, IFR jets, even on the busiest routes into our busiest aerodrome, lose separation services. In some of the less busy places (e.g. Launceston), they don't even have the possibility of a radar service to alert them - assuming the VFR is painting on radar.

PS - DOn't give anyone any ideas! The second our 'bugs' become 'features', we will have to start paying for them!!!!:D ;)

tobzalp 13th Nov 2003 09:03

Point of note to consider. Using the logic that there is a massive increase in controlled airspace (E), there are massive restrictions placed on VFR aircraft as well.

A class is introduced above E over all of CTA. The J curve for example has today (pretty much) G to A085, some E between SY and CG A085 to F125, C F125 to F285 and A above. Post NAS the C goes and E and A come in with A above F180 all the way up. So 9000 feet of potential VFR activity is gone. That's some 35% ladies and gents.

So here is the NAS model simplified.

More Controllers required.
Less service given to more aircraft
Costs Increase
VFRs have a 35% reduction in allowed airspace
VFRs must remain clear of IFR routes and all approach and departure paths
There are no frequency boundaries
There are no frequencies
Did I mention that it is going to cost more?
Aircraft IFR can enter supposed controlled airspace without a clearance (IFR Pick UP)

Add to this that the exemption for Flight without a transponder in E within 40nm of a D tower is added (no glider flying in the E steps above Caboulture or in the Steps above Alice Springs I'm affraid guys).

If I were a VFR pilot I would feel pretty cheated. But hang on, this is all designed for the VFR pilots, Isn't it?

snarek 13th Nov 2003 09:14

tobzalp


VFRs must remain clear of IFR routes and all approach and departure paths
Where did you get this from, point to a reference please. My reading of the available info leaves me with the opinion we should avoid flying through instrument approaches (which I do anyway) but nowhere do I find the much vaunted requirement to avoid routes.

Essentially, that is impossible unless I adopt the same navigation techniques I use in my yacht!! :E

The smart thing (which we probably all do anyway) is, if VFR in VMC avoid non-quadrantal in E or G above LSALT. But then, if it is VMC why fly 'on the dials'???

AK

Shitsu-Tonka 13th Nov 2003 11:17

It seems to me there is overwhelming logic and evidence to discontinue with this debacle. Nobody is better off except the Air Traffic Controllers who will be recruited to make it work - apart from the fact they won't be able to do their primary job - separating aircraft.

The only way it can therefore continue is by pure bloody minded determination of the political kind with individuals of the character that can push on and through in spite of all the contadictory facts blocking their paths.......... batter up?

(It might also be said that these types may also possess a demonstrated ability to flip-flop at the 11th hour..... hmmm? Where can we find someone like that???)

Meanwhile the NASOMETER $$$ keeps adding up --->>
http://www.greenindconsulting.com/cl...ator_anim2.gif
and YOU are paying for it

tobzalp 13th Nov 2003 11:21

From the Dotars Web site Pilot education online version (poor format due cut and paste)


VFR pilots should avoid when practicable areas where
IFR flights may be in a holding pattern:
Holding patterns are depicted on ERC-Low charts as
an oval track e.g. left hand pattern centerd on NICKY
VFR pilots should remain clear of GPS
approaches:
IFR flights will track to the open triangle and
begin the approach from there
If there is more than one open triangle an IFR
flight may begin from any of them
Copies of most instrument approaches are available
from the Airservices Australia website:
http://www.airservicesaustralia.com/...re/aip/dap.htm
IFR flights will track to the open triangle and begin
the approach from there
If there is more than one open triangle an IFR
flight may begin from any of the positions
Copies of most instrument approaches are available
from the Airservices Australia website:
http://www.airservicesaustralia.com/...re/aip/dap.htm
Pilots operating VFR should be aware of airspace where there may be a concentration of aircraft
operating IFR. This is particularly important in proximity to non-towered aerodromes. Remain
vigilant when operating in the vicinity of arrival/departure tracks to runways and navigation aids
Ask an IFR pilot or instructor about areas of high IFR traffic at your aerodrome
INSTRUMENT APPROACH (NDB/DME)
INSTRUMENT APPROACH (GPS)
HOLDING PATTERN
VFR flights should remain clear of instrument
approaches:
Holding patterns in Class E airspace around Sydney
are shown on VTC and VNC charts as a star
IFR flights may be holding in Class E
AVOID HIGH TRAFFIC AREAS


Plus I forgot about turning on those lights below A100. More bulbs to wear out faster. I bet the Government will pay for the extras because they are paying for ADSB afterall, aren't they?
:yuk: :zzz:


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