Congratulations to the RAAA – TCAS cost savings

[Dick Smith]

Most people know that we in Australia have the most onerous transponder requirements in the world for VFR aircraft. I am proud of this because I introduced them at the time I was CASA Chairman and Mark Vaile was the Minister for Transport.

This was introduced with the agreement of the general aviation associations even though a cost benefit study would have most likely shown that the criteria was not met. Of course, if the industry agrees to a more onerous and safer requirement that is allowed by the legislation this is ok.

Now look at the regional airlines – their organisation the Regional Aviation Association of Australia (RAAA) has been incredibly successful in preventing the introduction of TCAS requirements, which are mandatory in every other modern aviation country in the world. That is the requirement that air transport aircraft between 10 and 30 passengers have TCAS.

The situation at the present time is that there are airline aircraft operating in Australia that could not be operated in any other modern aviation country in the world.

I also find it interesting that the chief pilots of these regional airlines that have fought so strongly against the introduction of the North American NAS with more Class E controlled airspace remain silent about this major safety deficiency.

We all know the history of TCAS – if a professional pilot has the TCAS actually turned on and complies with the resolution advisory there has never ever been a collision – ie 100% safety record.

Of course, TCAS in regional airlines would work even better in Australia because we have the mandatory requirement for transponders in Class E. For example in the USA, there is no mandatory requirement for transponders below 10,000 feet in the E airspace above Class D.

It is an extraordinary compliment to the lobbying powers and the political influence that the RAAA has with the regulator that has prevented this safety requirement from being introduced in Australia. And it is all just to save a few dollars.

It seems strange to me that an organisation that purports itself to be there promoting safety for regional airline passengers can be so powerful in preventing the introduction of a basic safety requirement – that would cost no more than 60 cents per passenger per flight.

[tobzalp]

Which reminds me, which stage of NAS will the requirement for transponders below 10,000 feet in the E airspace above Class D be removed? I couldn't find it in the documentation.

[dragonflyhkg]

Dick, et al,

These same people, that are quietly lobbying their perceived interest in cost savings without TCAS, are also the ones vociferously complaining about the traffic conflicts that are becoming a more regular event around the regional airports of Australia.

The RAAA and its member airlines have demonstrated their willingness to be out of step with the aviation environment in Australia, and for that matter the rest of the developed world, on the issue of TCAS. They appear to be motivated by issues of cost to their business operations. In my book, that’s profit before safety. Neither the regulator nor the rest of the Australian aviation community should accept such a position. We all have a safety responsibility within the aviation system and we don’t have the latitude to “cherry pick” the areas in which we are prepared to meet our responsibilities.

Providing and operating a TCAS system does come with a cost, as does operating a transponder, but it’s a small cost in comparison with the vast majority of other aircraft costs.

I recently purchased a small format transponder for fitment to my recreational aircraft. The difference in price to obtain Modes-S now was about AUD $1,300 over and above Modes-A, C. The unit is already ADS-B compliant and I’ve made a decision to go ahead with Modes-S now. The responsibility toward an improved safety outcome requires it.

Arguments against transponder fitment on the basis of costs and power requirements have been largely mitigated in the past five years. The available options have increased significantly in this period. What’s happened to TCAS cost over this same period?

Frankly, waiting for the ADS-B process to be finalised in Australia before addressing the Mode-S side or TCAS side (interim) of the equipment requirements means the waste of a considerable opportunity to improve the safety of operation in an environment that has amply demonstrated a growing potential for incident or worse. It’s going to be an interesting incident investigation when the regional airliner without TCAS meets the Mode-S equipped conflict; an incident or worse when there could have been a progressive deconflicted resoltion advisory for at least one party. That’s a compelling case for all parties that cannot be ignored.

The other side of the equation that must be upheld is the reporting of traffic conflict incidents. This data is continuously required now to decide which elements of the debate are fact and which elements are fiction.

[CaptainMidnight]

because we have the mandatory requirement for transponders in Class ENot quite - my underlining:AIP GEN 1.5-9:

6.1.2 All aircraft, except aircraft operating to the VFR which are not fitted with an engine driven electrical system capable of continuously
powering a transponder, must be fitted with a serviceable Mode A/C or Mode S SSR transponder when operating in Class E airspace.

http://www.casa.gov.au/rules/orders/095.htm

Look at parts 95.8 / 95.10 / 95.12 / 95.14 / 95.32 / 95.54 / 95.55. You will see these types are permitted to operate in class E in VMC, and clearly most if not all do not have electrical systems capable of powering a transponder. So the AIP reference backed by CAR (174A?) means to me they don't need to operate a transponder in class E.

Which brings us to the safety of class E airspace debate .......

[emu787]

Hello Dick

I totally agree with you that TCAS is a REQUIREMENT in modern aviation even if it only adds another important safety element in our complex aviation environment....it gives the crew a realtime picture and I am sure in a few years it will be superseded with something more magical.

It saved my bacon overseas under procedural control and a limited english environment!

Just on a point though, the tragic B757 DHL-TU154 midair over Europe a few years ago, TCAS worked perfectly in both aircraft, unfortunately the B757 crew complied with the RA and the TU154 Capt. wanted to but then decided to follow a fatal ATC instruction. Not a perfect system due to the human interface ie. not a 100% record.

by the way still in the heart of Europe displaying my COMPANY ISSUED ID. CARD.........sorry Dick just another chapter that should have been in your book.....have you thought about a sequel!!!

Emu

[SM4 Pirate]

but then decided to follow a fatal ATC instruction Well yes, but. Without TCAS in that specific event, the "fatal ATC instruction" would have been a life saving instruction... "There but for the grace of god go I".

[Jetpipe2]

I agree that TCAS is a great "last line of defense" and I hope you also agree that it should be used as such?

With a fairly small fleet of aircraft in the 10 to 30 seat field it may be a good idea to fit them all with TCAS, but why not make it all turbine aircraft or all passenger carrying commercial aircraft? After all the pax in the back of a Baron is entitled to the same level of safety as that of a pax in a metro II or 23, etc.

We have numerous odd "lines in the sand" in our curent regs and so maybe getting that sorted out is a good starting point.

There is one major safety improvement that we can make and wouldn't cost much. Lets lobby CASA to make it mandatory for all airports with an instrument approach to be a CTAF-R! Oh and get everyone to turn their radios on and talk when they get there!

I know that a great deal of regional aircraft operators would be able stop using their TCAS as a sudo radar systems to dodge VFR traffic not required to talk at an airport.

[Capn Bloggs]

Dick,

I am proud of this because I introduced them

Only because we flatly refused to accept E airspace without mandatory transponders! You were all for "free in E and G", which, if you had your way, would have allowed NO RADIO aircraft to mix it with RPT jets, for goodness sake.

Who, in their right mind, would allow a non-transponder lighty to swan around through the airspace over a busy airport, requiring A380s to take avoiding action after the A380 pilots had finally spotted the lighty? Dick Smith. :yuk:

Otherwise, I agree that TCAS should be mandated in every commercial turbine aircraft, provided transponders are mandated in aircraft that operate into CTAF Rs (if they can power them). :ok:

[Dick Smith]

CaptainMidnight,

What you have to look at is the “mix” of VFR aircraft with regional airlines. It is obvious that over 95% would have a proper engine-driven electrical system. If you capture 95% of the traffic with a transponder, that is a hell of a lot better than zero.

[Atlas Shrugged]

Anything that is capable of aerodynamic or aerostatic flight in any airspace anywhere SHOULD have a transponder.

....the end

[CaptainMidnight]

What you have to look at is the “mix” of VFR aircraft with regional airlines. It is obvious that over 95% would have a proper engine-driven electrical system. If you capture 95% of the traffic with a transponder, that is a hell of a lot better than zero.I don't understand the point you're trying to make. As far as I am aware, no-one is arguing for zero transponders in class E.

What I'm saying is that if you are pushing the point that class E has a high degree of safety because of the 'mandatory" transponder fitment then that is incorrect, because my interpretation of the regs is that many sports aviation types can now operate in class E in VMC without a transponder [if they have no electrical system capable of powering one] and no communication with ATC.

From the exemptions list, in addition to gliders these sports aviation types include hang-gliders, some types of ultralights, trikes and gyrocopters. I have no idea, but the number of these in the country might equal the number of light aircraft.

So your assertion that 95% of the aircraft operating in class E will have a transponder is debatable, particularly over time [and in the vicinity of places like Albury], and where class E corridors are extended down to the circuit area of aerodromes.

I suggest that regional aircraft mixing with such types, largely invisible and nil communications isn't an acceptable situation.

[Jabawocky]

Atlas Shrugged:ok::ok:
Anything that is capable of aerodynamic or aerostatic flight in any airspace anywhere SHOULD have a transponder.

....the end

And I'll raise you.........an ADSB transponder combining both Mode A/C and ADSB, all in one! That way any RPT with TCAS and any ATC (with proper low level coverage) will see you, long before they see you!

It aint hard.....just hard to get the knockers to listen:ugh:.

J:ok:

[bushy]

And billions of dollars for all the fancy electronics.

[gaunty]

:ugh::ugh::ugh::ugh::ugh::ugh::sad:

[Jabawocky]

OK Bushy and Gaunty......its the Billions of dollars you are worried about now is it? Well lets just swith off ALL the radar heads, might as well turn of the terminal areas as well, and ditch a CTA requirement for mode C then shall we?

:ugh::ugh::ugh::ugh::sad:

We are wasting so much on this stuff now, why continue with it when for the same buck you can have much better?

To many flat earthers on here!

J:ok:

[Capt_SNAFU]

Atlas Shrugged
Quote:
Anything that is capable of aerodynamic or aerostatic flight in any airspace anywhere SHOULD have a transponder.
....the end
And I'll raise you.........an ADSB transponder combining both Mode A/C and ADSB, all in one! That way any RPT with TCAS and any ATC (with proper low level coverage) will see you, long before they see you!
It aint hard.....just hard to get the knockers to listen.
J
:D:D
I agree completely with the above statements. On another matter anything thing that flies should have a radio. This is the 21st century for :mad: sake.

[Dog One]

Can some one tell me why we need E airspace? Is there a cost saving to IFR movements, does it allow more IFR movements in a given area. Does it require less attention from ATC, there fore less controller hours? What are the benefits?

[RENURPP]

I have two question.
Has there ever been a mid air collision between air transport aircraft between 10 and 30 passengers in Australia?

Do that have a 100% safety record regarding mid air collisions?.

Near misses don't count as a TCAS RA could be considered a near miss.

[Jabawocky]

RENURPP

Whats your point? As you say a TCAS RA is avoiding what might have been. I think the chances of two Dash 8's at Emerald coming together is pretty slim, one operator, one service at a time. They might see a competitor in a Metro if they are extremely lucky.

However around those 10-30 RPT's is a much higher volume of AG planes, GA planes and RAA and GFA's members, so TCAS and a transponder is a damn fine idea. And while we are at it as technology now permits.......get the lot in one box, refer my post above.

Capt_SNAFU
Thanks, PM me if you wish to join the push for common sense!

J:ok:

[Dick Smith]

Dog One, you have made 256 posts on PPRuNe, yet you do not know the benefits of Class E airspace. Could it be that the situation which existed in Bundaberg could be avoided? This was a situation where an airline aircraft and another IFR aircraft with a professional pilot were performing the same instrument approach at the same time in IMC. Unfortunately one aircraft was on the wrong radio frequency - a pretty simple mistake.

Or could it be that the incident at Orange could have been avoided? This was the incident where a Rex aircraft was approaching from the east and an IFR Baron with a professional pilot was approaching from the west – both in cloud at the same time. When the Baron needed to do a missed approach it was heading straight into the IFR airline aircraft. The only way it could save the day was by illegally turning off the missed approach. Luckily there were no mountains there.

Class E means that when you are in cloud, you get a proper radar or procedural separation from air traffic control. Surely that is better than a do it yourself “no standard” system.

More importantly, when in radar Class E, the air traffic controller will not let you go below the legal minimum altitude until you have reported that you are in VMC or the controller can see that you are on the correct approach. Both of these would add to safety. Just look at what happened with the professional pilot at Benalla – six people died.

Atlas Shrugged, you say that anything capable of “aerodynamic or aerostatic flight” should have a transponder – but this thread is about the fact that at the present time we don’t even have TCAS in 10 to 30 passenger aircraft. Why are you asking for something that doesn’t exist anywhere in the world, yet not supporting a standard requirement which does exist in every other modern aviation country?

I look forward to your advice.

[Wizofoz]

Dick,

Your thrust in this post is, as it has been in many things, that the burden of cost for air safety should be almost entirely borne by airlines.

As I have mentioned before, TCAS is most effective when BOTH aircraft are equipped, and BOTH pilots are trained to react to RAs.

Therefore, to achieve the level of safety your desire, ALL aircraft capable of powering a transponder should ALSO be equipped with TCAS, and all pilots initially and recurrently trained in its use. Please bear in mind I say this in order to protect the traveling public. A light aircraft so equipped is less likely to cause an accident with the RPT aircraft YOU suggest should be the only one with the costly equipment.

The only case against this would be on the basis of cost- and it's obviously a good case. You were something of a pioneer in publicizing the fact that cost vs safety MUST be a primary consideration.

Therefore, would you please publish the factual information (and not just "They do so we should, I mean actual studies)that shows that equipping 10-30 seat RPTs with TCAS, whilst they mix with VFR aircraft flown by PPLs and with no such equipment, will reduce the incident of mid-air collisions in Australia(which, currently, is zero to my knowledge)

[Dick Smith]

Wizofoz, no, I have never said:

that the burden of cost for air safety should be almost entirely borne by airlines. In fact, it is completely the opposite. As I explained, I introduced the mandatory transponder requirements for VFR aircraft in Class E. This is not a requirement (as far as I know) anywhere else in the world. This clearly means that wherever we upgrade to Class E airspace, we also ensure that all aircraft are transponder equipped. This is logical.

However in Australia we have 10 to 30 passenger airline aircraft without TCAS. This means that in a non-radar environment (which many of our airports are) the advantage of the costly transponder (which VFR owners have agreed to install) is completely negated.

If you constantly come back and say that there must be a one-way ratchet which increases costs to VFR aircraft owners, but airline owners should not even have to comply with existing accepted world standards, this is ridiculous.

In relation to factual information about TCAS improving safety, you simply need common sense. At the present time, most aircraft that mix with 10 to 30 passenger aircraft in the circuit area are equipped with transponders. Therefore it is logical that safety will be improved if the RPT aircraft are TCAS equipped. You can do 10 years of study if you want to, but even if one conflict is resolved because the airline aircraft has TCAS, it is better than not having TCAS in the first place.

[Jabawocky]

Dick, your points are valid however, to have that extra service of class E you describe you have to have the radar coverage in the first place.

I understand that at Benalla its not all the way to the ground nor is it at Bundaberg either. So this is a classic reason for introducing ADSB accross the fleet (you need 100% because you will not have any primary returns in this system) so why not support the coverage first then push for the ATC service.

Cheers

J:ok:

[RENURPP]

Dick,
At the present time, most aircraft that mix with 10 to 30 passenger aircraft in the circuit area are equipped with transponders. Therefore it is logical that safety will be improved if the RPT aircraft are TCAS equipped.
can you advise what benefit TCAS is in the circuit area with high density traffic??

[Dick Smith]

Jabawocky, you state:

to have that extra service of class E you describe you have to have the radar coverage in the first place. Gad, you are stubborn! The US has 50% of its IFR approaches in Class E airspace without radar coverage. They use the advantage of radar where they have it, and the advantages of procedural separation where they don’t.

A Class E procedural separation service would have reduced the chance of the two incidents I gave as examples in an earlier post – where two IFR aircraft were in cloud at the same time and nearly collided.

We have excellent radar coverage between Hobart and Cairns. Why not use it there?

In the case of Benalla, there was excellent radar coverage down to the start of the approach. That is how the ATSB report showed the actual position of the aircraft.

As stated previously, in the case of Bundaberg both aircraft were in cloud attempting the same approach at the same time. In fact, the captain of one aircraft asked the co-pilot to turn off the strobe lights, and then found out later that it was the strobe lights of the other aircraft. In this situation at Bundaberg, Class E would have reduced the chance of a horrendous accident.

The more you resist change, the greater the chance that we will have an accident. Isn’t it interesting that after 15 years of work by myself, we still don’t have one bit of Class E terminal airspace. I have heard a story that Airservices are going to “try” it at Ballina. Well, when they do it will be 15 years too late and you will find that everyone will say, “This is fantastic. This improves safety. It does not unduly delay aircraft. Why weren’t we doing this 20 years ago?”

RENURPP, I can assure you that TCAS has a benefit even in high density traffic areas, but obviously a greater benefit where the traffic density is low – which it is at most Australian non-tower airports. Why do you come up with every single furphy to try to stop a proven safety feature? Why not simply say, “Yes, it would be a good idea if the RAAA was responsible and did not constantly campaign to prevent CASA from bringing in a safety requirement that all other leading aviation countries have accepted for years.”

[Wizofoz]

Why not simply say, “Yes, it would be a good idea if the RAAA was responsible and did not constantly campaign to prevent CASA from bringing in a safety requirement that all other leading aviation countries have accepted for years.”

And why SHOULD we say that? Oh, that's right! Dick says so, so it MUST be true!!

Are you aware, for example, that most VFR aircraft in Europe have Mode A TXP only, rendering the TCAS that IS fitted to RPT aircraft much less useful (and in my opinion actually counter productive as you get a great many spurious TAs).

Dick, one point I've made more than once( and you've ignored) is that TCAS is much more effective if BOTH aircraft are equipped and BOTH pilots are trained in it's use.

Why do you not propose fitment of TCAS to ALL aircraft? Cost? If so, why isn't cost a reasonable reason NOT to fit them to small RPT aircraft? Oh that's right! Because you've had a good think about it, and as your common sense is better than everyone else's, it must be the right thing to do.

[RENURPP]

Dick,
If you can assure me, please do so.

[GaryGnu]

Dick,

I am curios as to what prompted this latest tirade.

I cannot find any comment about TCAS by the RAAA on their website.

Would you care to illuminate us with your reasons for the latest outburst?

[tobzalp]

I ask again.

Which stage of NAS will the requirement for transponders below 10,000 feet in the E airspace above Class D be removed? I couldn't find it in the documentation.

[peuce]

Dick, you said:

"we still don’t have one bit of Class E terminal airspace. I have heard a story that Airservices are going to “try” it at Ballina."

Call me a fundmentalist luddite, but I can't see how vectoring 2 IFRs at Ballina ... while there are 13 bugsmashers in the same area ... invisible to, and immune from, the Class E Controller .... will be a safer option :confused:

[Capn Bloggs]

Well said Puece. :ok:

The most life-threatening situations I have been in in Dick Smith alphabet soup airspace have been unannounced VFRs popping up in front of me, not IFR. Had they not had [optional] transponders, things could have got very close.

Dick, mandate transponders in all aircraft within 30nm of CTAF Rs and you'll have my support for mandatory TCAS.

Secondly, no comment on the A380 pilots looking out the window for lightys to avoid?? or indeed the whole "VFR operate in a different world and so should be ignored"/Class E thingee? Cat got your tongue old chap?

[vans]

Wizofoz, you said “Dick, one point I've made more than once( and you've ignored) is that TCAS is much more effective if BOTH aircraft are equipped and BOTH pilots are trained in it's use.”

Yes, you have mentioned this before, and I don’t think there would be too many in this site who would argue about the obvious safety benefits of both aircraft having TCAS, but Dick is attempting to get the RAAA to introduce TCAS into regional airline aircraft as a starting point. I’m sure an intelligent person such as yourself would agree that having one aircraft equipped with TCAS in an environment of other aircraft equipped with transponders, increases safety greatly because then at least one aircraft can take the necessary avoiding action. Your chances of convincing the entire GA fleet that they should all equip with TCAS on the off chance that some of them may end up in the same airspace as a regional airline aircraft is , to put it bluntly, almost zero at the moment. Perhaps later, when regionals set the correct example and do what the rest of the civilized world has already done, the obvious safety benefits will filter down to GA, and they will follow.

[werbil]

What is the big deal with class E airspace?

Our class G is unusual in that IFR aircraft are provided with traffic information about other IFR aircraft. It is my understanding that in many other parts of the world, IFR in G get zip, unless in radar coverage where a service may be available.

As I understand for all intents and purposes in Australia the only differences (outside CTAF's) between E & G are:
E - clearance required for IFR, G - reporting required for IFR.
E - separation provided between IFR and IFR, G - traffic information provided between IFR & IFR
E - transponder mandatory all aircraft, G - transponder not required.

Class E is designed to protect IFR from IFR, not IFR from VFR. You will still have the same number of "bugsmashers" flying without ATC / FS input irrespective of whether you are flying in G or E - how can it possibly be less safe?

So I would like someone to explain to me how G is safer than E as I must be missing something (Scurvy are you allowed to play yet / how was the holiday?)

Yes the highest risk of collision is the circuit. If the ADS-B proposal is implemented as proposed in the JCP there will be mandatory transponder carriage in CTAF(R)'s.

vans :ok::ok::ok: Well put.

[peuce]

For TCAS to work, the target aircraft must have a working transponder. Do all/most target aircraft have working transponders in the airspace that Regional aircraft operate?
In E Airspace, IFR aircraft are vectored/instructed to manouver. This manouvering takes no account of unknown aircraft in the same airspace. In G Airspace, IFR aircraft, once advised of IFR traffic, make their own determination about when/how/if to manouver

[Atlas Shrugged]

Why are you asking for something that doesn’t exist anywhere in the world, yet not supporting a standard requirement which does exist in every other modern aviation country?


Dick,

Tell me exactly where it was that I asked for, or said anything of the sort!

Take your blinkers off, replace them with your glasses and please go back and re-read what I posted. I simply made a statement. Nothing more, nothing less.

:mad:

[bushy]

For all these wonderful systems to work, it is necessary to have some effective system of good maintenance, or test and replacement readily available in all parts of the country. It does not exist, and without it you can expect the system to be unreliable.
Heads have been stuck in the sand for decades, and still are.

[peuce]

Werbil, you said:

Our class G is unusual in that IFR aircraft are provided with traffic information about other IFR aircraft. It is my understanding that in many other parts of the world, IFR in G get zip, unless in radar coverage where a service may be available.

You might find it interesting to know that in the U.S. IFRs are separated in G Airspace. According to the FAA, they expect IFRs to comply with clearances and direction in Class G Airspace.

[vans]

Peuce said

“In E Airspace, IFR aircraft are vectored/instructed to manouver. This manouvering takes no account of unknown aircraft in the same airspace. In G Airspace, IFR aircraft, once advised of IFR traffic, make their own determination about when/how/if to manouver”

It is my understanding that there should be no unknown aircraft in E airspace in a radar environment because all aircraft in E must be transponder equipped. In a non radar E airspace environment there also would be no unknown aircraft to an IFR aircraft if the IFR was equipped with TCAS. I realise that TCAS is a last line of defence, but it does increase safety and this is all that I imagine Dick is argueing for with the regionals. The other line of defence that you have as an IFR aircraft in non radar E is that whilst in cloud there should be no unknown aircraft at all. So, to an IFR aircraft the only unknown aircraft in E would be in procedural airspace, in visual conditions, and then only if the IFR didn’t have TCAS. Of course there is also the mark 1 eyeball in visual conditions too!

[gaunty]

vans

As we know,
There are known knowns.
There are things we know we know.
We also know
There are known unknowns.
That is to say
We know there are some things
We do not know.
But there are also unknown unknowns,
The ones we don't know
We don't know. D Rumsfeld

As usual and not unsurprisingly the debate centres around the "regionals" in the J curve. It might surprise Messrs Smith et al that there is a biggish part of Australia west of Bourke.
In my neck of the woods the types and numbers of them used in the FIFO business way outnumber the regionals and high frequency yet to private or unlicensed strips often only separated by tens of miles and in any event surrounded by private operations.
I personally dont care if you mandate transponders in EVERYTHING and REQUIRE passenger carrying aircraft regardless of seat numbers to have TCAS, or, get this 90% ADSB out thing going regardless of its technical eloquence/elegance.
Either way the biggies/fasties at least get to "see" the threat. The "threat" may never ever know how close he came, who cares, as long as it wasn't together.

Bloggs knows of which I speak. :ok:

[vans]

Gaunty

Excuse me old chap, but I was attempting to not drift off the thread with my posts! If you check Dick’s original post you will see that it was specifically addressed to the RAAA and the regionals, hence I too was addressing this section. Nobody mentioned aircraft west of Bourke unless they happened to be a regional. In any case, if you want complete knowledge of the things we don’t know everywhere, then you best be barracking for controlled airspace over the whole of Australia right to the ground. In the meantime, I’ll settle for a few more TCAS’s in the regionals as a starting point, which is what this thread is supposed to be all about

[CaptainMidnight]

vans saidIt is my understanding that there should be no unknown aircraft in E airspace in a radar environment because all aircraft in E must be transponder equipped. In a non radar E airspace environment there also would be no unknown aircraft to an IFR aircraft if the IFR was equipped with TCAS. I've already said twice here that mandatory fitment of transponder is NOT repeat NOT required for all aircraft types in class E:

http://www.pprune.org/forums/showpost.php?p=3640684&postcount=11

and

http://www.pprune.org/forums/showpost.php?p=3638553&postcount=4

[vans]

Yes, thanks for that, technically you are correct. But in reality, what exactly in terms of risk are you worried about with your exemption list?

Quote “From the exemptions list, in addition to gliders these sports aviation types include hang-gliders, some types of ultralights, trikes and gyrocopters. I have no idea, but the number of these in the country might equal the number of light aircraft.”

Without postulating about the future, the lowest level of E airspace in Australia at the moment is 8500 ft., including that at Albury. I don’t know of too many aircraft in the above list without a proper engine-driven electrical system that would have the ability to cruise above 8500 ft, save gliders, let alone those pilots who would deliberately attempt it in E airspace in such aircraft. This is not to say that none are capable or that none would attempt it, but I think most reasonable people would conclude that a high degree of safety does in fact exist in E airspace because of the mandatory fitment of transponders in all aircraft with engine driven electrical systems capable of powering a transponder, despite the exempted list.

Notwithstanding the above, if your argument is solely about the correctness of the mandatory transponder statement and nothing else, then I will concede your point.

[peuce]

Mr VANS,

We were specifically discussing a Class E approach service at Ballina ... not 8500ft.

Also, if you exam the traffic mix types around Ballina, I think you would be in a for a bit of a surprise.

[vans]

With regard to a potential class E approach service at Ballina, there is already a provision in the AIP for an aircraft in Class E airspace (and class D) upon request and if so prescribed by the ATS authority, to be cleared without separation being provided in respect of a specific portion of the flight conducted in VMC. AIP Gen 3.3 (1.5) refers. It may have the potential to allow you to arrange your own separation in class E once in VMC, and particularly in the areas that you are concerned about in regard to unannounced VFR traffic, just as you would do in class G in similar circumstances. In the meantime, you may have the added protection of being kept fully aware of other IFR aircraft, because you are still theoretically in Class E airspace. Add a TCAS to your aircraft to further mitigate potential risk and you are considerably better off than in class G at the same place, at least whilst in cloud. Might work – I don’t know……over to you.

[Spaz Modic]

Hmmm. Where'd Dick go? :uhoh:

[CaptainMidnight]

vans

Hang gliders operate up to A100 regularly, particularly in Victoria. One was observed within CTA (incident a few months ago NE of Adelaide), and if you operate up to A100 in NE Victoria you can expect to be in the same airspace. The terrain height being up to 7200FT means one flying at A100 is not unreasonable.

The points I'm making & reinforcing are

mandatory fitment of a transponder is not required for all aircraft types to operate in class E, therefore various parties claiming that within E all traffic is known is incorrect, and

the liklihood of encountering such non-transponder equipped unknown traffic will increase significantly if & when class E is extended down to 700FT AGL/SFC at aerodromes.
:ok:

[LeadSled]

Spaz,

Hmmm. Where'd Dick go?
Maybe he is off flying somewhere not quite as anal as Australia.

Werbil
What is the big deal with class E airspace?
You really don't understand, do you. You can't argue your perfectly correct factual logic like the rest of your post, you really can't let facts spoil a good story.

Take a leaf out of Midnight's "The E of Doom" (with apologies to the author of the Eye of Doom)

The points I'm making & reinforcing are
* mandatory fitment of a transponder is not required for all aircraft types to operate in class E, therefore various parties claiming that within E all traffic is known is incorrect, and
* the liklihood of encountering such non-transponder equipped unknown traffic will increase significantly if & when class E is extended down to 700FT AGL/SFC at aerodromes.

Now, Werbil, as you and I know, that traffic is already there, but much of it doesn't have to have a transponder, because it's G (the ones wot 'ave a generator with a min. 5 watt output) but now in E they will have to have a transponder, and Midnight will suddenly know about them (provided he is not flying a little Regional -- which Australia has exempted from having a TCAS --- unlike ICAO/most of the rest of the world -- )

And what was G suddenly becomes more dangerous as E because you now have some information on traffic that you didn't have when it was G --- an unknown unknown has suddenly become a known unknown.

Peuce, what a wonderful example of "a little knowledge is dangerous.
----in the U.S. IFRs are separated in G Airspace.
Legally, no they are not, and there is no such thing as a "clearance" in G --- if you are in court ---- but who would knock back the help of the radar man just because you have slipped through a line on the map --- unlike here ---- "leaving controlled airspace - radar services terminated -- clear to leave this frequency" ---- or words to that effect.
You do know, do you, that in most of the lower 48, E comes down to 1200 or 750 AGL --- except in Alaska and the mountain regions G is a bit hard to find.

Maybe Dick has to get away every now and again for his sanity.

Tootle pip!!

PS: Gaunty, wakey wakey, time for an update, old chap!! ---- RAAA has been the Regional AVIATION Association of Australia for years, "Airline" got dropped not long after ANSETT became a footnote in Australian aviation history, if my memory serves me correctly. Many of your mates in the WA FIFO business are the backbone of the RAAA, and guess what, at least one is removing a couple of seats from a Dash 8, to bring it under 30 seats, to take advantage of the Australian ICAO non-compliance on (non) fitting TCAS I.

Obviously this operator does not regard a TCAS as affordable safety.

[peuce]

Leadsled,

To quote from the Broome Airport Study, which is linked to in another thread:

The report by
Captain Beville-Anderson (2003, A Study of Airspace and Procedures in the
US NAS, Australian Federation of Air Pilots. Feb–Mar 2003) reported on an
interview with the FAA in which:

Mr Reggie Matthews, Manager Airspace and Rules Division, who is the FAA
executive with policy authority to make an interpretation on ATC regulations,
stated that FAA policy requires IFR aircraft in Class G airspace to operate on a
clearance. This policy is not documented, however Mr Matthews advised that
it is current custom and practice, both for industry and FAA, to function in this manner, and that if an interpretation was required it would come to him for decision.

and in another part of the same interview:

The FAA acknowledged that they are providing a de-facto Class E service to
IFR aircraft in Class G, and they have no intention to change.



My point is that ... all is not what it seems.

[LeadSled]

Peuce,

Thank you for that, probably unknowingly, you have supported EXACTLY what I said:

FAA policy requires IFR aircraft in Class G airspace to operate on a
clearance. This policy is not documented, -------

Quite so. It is not the law.

This policy is not documented, however Mr Matthews advised that
it is current custom and practice, both for industry and FAA,-----

Quite so --- not even documented ----- " yer 'onour, this 'ere pilot broke a law wot we don't 'ave, but we rekon we should 'ave, please bang 'im in the pokie".

The FAA acknowledged that they are providing a de-facto Class E service to IFR aircraft in Class G, and they have no intention to change.

Quite so --- defacto --- practice and custom, and it works very well, too, even though it has no legal basis ---- but any such "clearance" is not enforceable at law ---- because the law does not exist.

This is a good example of why the US system works so well, as it does, common sense and cooperation, instead of rigid adherence to rigidly defined and documented ad infinitum as nauseum "rules".

American "can do" versus Australian "can't do".

I am well aware of Toaster's visit to US, for the AFAP, and report, it's in my library ---- in my opinion so typical of many by people over the years, they find the US system works really well ---- but all know "it wouldn't work here". The one that really gets me is "the culture is different" ---- and the really professionally insulting claim that Australian pilots can only work in a "culture" of detailed, prescriptive and rigid "rules".

Who was it said:" When I hear culture, I reach for my gun".

Amazing how easily and seamlessly Australian pilots adapt the the US "culture" when they are flying in the US and marvel at what a friendly, flexible and common sense system it is !!

One of the recent statements made by a "representative" not entirely un-adjacent to the AFAP, has been the claim that "see and avoid" can't work in Australia ---because "Australian pilots don't have a culture of looking out the window" . Hence the undocumented and highly suspect "pilot to pilot do it yourself ATC" that has grown up in Australia in lass G.

Even more reason why we should follow the same TCAS rules as the rest of the world.

Tootle pip!!

[peuce]

Leadsled,
Try looking at it from the point of view of us dumb aussies who haven't flown in the U.S.
It turns out that the yanks are providing a dodgy brothers control service in uncontrolled airspace ... because their "official" system obviously doesn't work.
Now you guys are telling us that we must be more flexible and take on a dodgy system ... as our official sytem. That is, we should fly into a bit of airspace and, depending on the mood, workload and interest of the controller at the time, we'll either get a traffic service, a separation service or, perhaps, no service.
The yanks HAVE to do that ...because their system is saturated and close to busted.
We don't.
I still feel that we are intelligent enough to produce a workable "official" system ... even if we have to begrudgingly revert to simplicity and go back to Controlled and Uncontrolled Airspace, with AFIZs at the Ballinas and Broomes. ...

[tobzalp]

No no no. If it is the way it is done and expected, it may as well be law. Exactly the reason why a work to rule is illegal industrially. You are expected to do what is expected of you even if it is not the rule.

[LeadSled]

Peuce,

Get yourself a diagram of US airspace, and see how little G airspace exists, except in Alaska.

To slightly oversimplify, in the "lower 48", all airspace above 1200' AGL (750' where there is an instrument approach) is Class E to the base of A. Far and away the great volume of airspace below the high level A is E.

Class B is confined to the major HCRPT hubs, generally topping out at 10,000, the lateral extent of the B "inverted wedding cake" is quite small, compared the steps into any towered airport here, whether C or D. C is generally a simple zone around airports that rate it, D similar but smaller and usually but not only GA/Commuter airfields.

Part of Toaster's problem with the AFAP report referred to was the problem of "divided by a common language", and questions asked in Australian were heard/interpreted in US, the US answers were translated into Australian, to the yank, his or her bum is a very different thing to your bum. To Toaster's distress, his interviewees didn't understand his continual queries about "mandatory" procedures.

Nobody denies the huge problems of ATC in the US, but they are problems of success, and the growth of traffic volumes around the major hubs, and the economic cost problems for airlines through these major hubs. FAA is not without serious management problems, but that's hardly unknown in CNS/ATM or CASA here, is it? As recently admitted in Congressional hearing in Washington by the ATA, the two biggest causes of airline delays are lack of real estate --concrete, and airline scheduling, followed by weather disrupting schedules.

None of this has much impact on other than the major hubs, and the long suffering pax, for the bulk of other than HCRPT the system is far from broke.

On this occasion I agree with Tobzalp, where an aircraft receiving an ATC "E" service (and it will only be in the vicinity of an airfield -otherwise it wouldn't be likely to be below 1200/750 AGL, except in an emergency) and it goes into G, there is nothing unlawful about continuing the service --- whereas, under Australian law, it is not really clear-cut. However, I think it is probable that the legal history here would support the US practice.

I recall coming into YSSY one evening, on right base for 34L, at 1500'. As we crossed the centreline headed for Stanwell Tops, I waited a few minutes then something along the lines of:
"Approach, PX-XXX, Abeam Coalcliff, maintaining 1500, leaving controlled airspace, advise frequency", there was no reluctance to getting us back to where we should have been, ie; continuing the service in G.

All that remarks along the lines of "---revert to simplicity and go back to Controlled and Uncontrolled Airspace, with AFIZs at the Ballinas and Broomes. ..." prove is that the ICAO risk management approach to provision of CNS/ATM services services has never taken root here, despite the acceptance of a risk management approach to "safety" in Australian industry generally. This reluctance to use hard numbers, and prefer untested and highly coloured assertions, is well in evidence in the various papers that are the basis of the JCP, ASTRA / ABIT etc.

The airline industry here simply cannot afford the cost of services that provide no measurable benefit, and providing CNS/ATM services beyond that necessary to achieve separation assurance standards is waste, but waste that has to be paid for ---- or if you prefer, unaffordable safety --- because it is no additional risk mitigation for the cost.

As a pilot, in the clashes between the "pilots" and the beancounters, only on rare occasions would I not back the beancounters, that way the company is more likely to survive and hopefully prosper --- they don't have the emotional involvement that makes formal risk assessment so difficult for pilots.

If anybody has any doubts about emotional involvement colouring views on air safety, have a look at the Flight Safety Foundation paper of about March 2003,( give or take a year and a month) about Australia's air safety record (such as it is).

Having said that, I must make it clear that I support TCAS as per FAA/ICAO, and it is here, now, with STCs for every relevant aircraft on the Australian register, at known costs, unlike ADS-B IN, which is only going to be another input to TCAS for HCRPT anyway ---- for the foreseeable future.

Tootle pip!!

[peuce]

Sorry, I'm a bit thick. I still don't get what you want Australia to adopt.

Granted, the U.S. (except Alaska) has minimal G Airspace ... and they separate inside it. We have a ****load of G Airspace ... do you want us to separate in it? Or only near the edges? Or, only when "appropriate"?

Considering some of the current coronial and air safety investigations going on ... which are delving into every word and punctuation mark of the documents ... I don't think ASA is brave enough to say "go for it boys ...you decide when to separate". Equally, I don't believe that Australian Controllers are willing to put their peckers on the chopping block.

The obvious solution is to replace all G Airspace with E Airspace, everyone who can ... get a transponder, RPTs get a TCAS.

Then we start running into surveillance problems, procedural separation, delays... Back to square 1

[LeadSled]

Peuce,

This thread started out discussing why Australia doesn't require some aircraft, such as the SAAB340, to have TCAS, why Australia does not conform to ICAO requirements, and many of us think it would be justified for Australia to catch up with the rest of the world.

At least one pilot union and the RAAA have been demanding all aircraft, or all aircraft around a CTAF(R) have a Mode A/C transponder ---- but what's the point if at least one aircraft does not have TCAS.

Tootle pip!!

[vans]

Ed Zackery LeadSled!

I was based in the US some years back for 6 months and experienced flying in all levels of their airspace up to FL490. There was no TCAS fitted to the aircraft I was in at the time, so I was probably blissfully unaware of what I didn’t know, but I do know that their system worked extremely smoothly and nothing was too much trouble for the US controllers. Surely there is someone here (Leadsled?) who can enlighten us to exactly how the US controllers handle separation of IFR traffic in E airspace when there may be non-transpondered hang gliders floating around at A100, (CaptainMidnight). There is no doubt that they do handle it, and handle it well. However, in Australia the main objection to the application of more E airspace, particularly potential E approach services to the lower levels (Ballina) seems to be that of the very possibility of having a close encounter with this non-transpondered traffic whilst being vectored to avoid other IFR traffic. How exactly is it done and why is it that we cannot do the same? C’mon Dick put your head back in here and explain please. I’m sure those who object to E would find it difficult to continue their arguments in the face of a reasonable and workable explanation to the fear they have of E being an unacceptable risk, particularly in the lower levels.

There is some level of thread drift in this discussion though!

[NOtimTAMs]

Just on the Ballina bit:

I go in and out of Ballina/Lismore frequently. SSR coverage doesn't begin until about 1300', so the "Class E" controller couldn't "see" circuit traffic anyway (there's ab initio GA & RAA training at YBNA). I can't see any safety advantage in keeping incoming IFR traffic on a different frequency to the CTAF circuit traffic until they're about in the circuit - unless the YBNA Class E FRQ will be the same as the frequency used in the circuit....and I don't think ATC want to hear all the circuit calls....

On a practical basis, CTAF-R here works - the lighties and RAA keep out of the way of the RPT and the IFR guys 'n' gals know each other's there (either from the preceding ATC or from their CTAF BCST) and keep out of each other's way, so why is class E needed? The only real IFR "overlaps" in crappy wx are between the GNSS RNAV approaches for YBNA RWY 06 & YLIS RWAYs 15/33.

[CaptainMidnight]

A) YMMM/YBBB C4610/07 (SPA) 10152335
B) 0711171824 C) 0711240914
D) HJ
E) HANG GLIDER CROSS COUNTRY COMPETITION 40 HANG GLIDERS OPR WI 110NM OF GULGONG POSN 3218S 14934S (12NM N OF MUDGEE)
SFC TO F130110NM radius takes in a bit of territory, and its Class E base 8500 immediately to the east of MDG.

And we regularly see NOTAMs re gliders operating in G & E up to FL245 (the base of Class A), nil transponder and normally not talking to ATC.

I would also be interested to find out if nil transponder gliders, hang gliders, gyrocopters etc. etc. can operate in class E in the U.S., particularly where it is down to SFC.

[LeadSled]

Midnight,

Why not have a look at the FAA AIM, it's all on the web, and convince yourself that what I am about to say is correct.

Except for the 30nm transponder veil centred on the airports justifying Class B airspace, there is no transponder requirement for ANY VFR in E, below 10,000 ft.

There are some variations to this for active TSRA ---- but this is Homeland Security stuff, not generally permanent, and not FAA, whose general "rule" is above.

The ADS-B NPRM makes more or less the same provisions.

Tootle pip!!

[vans]

So LeadSled, are we to presume then that in the US “E” airspace we have all types of IFR traffic being vectored to avoid collisions with each other amongst a possible army of unknown non-transponder traffic below 10,000ft?

You guys have never had it so good in Australian “E” – what are you worried about???????????

[LeadSled]

Midnight,
To save you the trouble of looking, from the current AIM.
--------------------------------------------------------------------------
The Class B veil.
Mode C Veil. The airspace within 30 nautical miles of an airport listed in Appendix D, Section 1 of 14 CFR Part 91 (generally primary airports within Class B airspace areas), from the surface upward to 10,000 feet MSL. Unless otherwise authorized by ATC, aircraft operating within this airspace must be equipped with automatic pressure altitude reporting equipment having Mode C capability.

However, an aircraft that was not originally certificated with an engine-driven electrical system or which has not subsequently been certified with a system installed may conduct operations within a Mode C veil provided the aircraft remains outside Class A, B or C airspace; and below the altitude of the ceiling of a Class B or Class C airspace area designated for an airport or 10,000 feet MSL, whichever is lower.


3-2-6. Class E Airspace

a. Definition. Generally, if the airspace is not Class A, Class B, Class C, or Class D, and it is controlled airspace, it is Class E airspace.

b. Operating Rules and Pilot/Equipment Requirements:

1. Pilot Certification. No specific certification required.

2. Equipment. No specific equipment required by the airspace.

3. Arrival or Through Flight Entry Requirements. No specific requirements.

c. Charts. Class E airspace below 14,500 feet MSL is charted on Sectional, Terminal, and IFR Enroute Low Altitude charts.

d. Vertical limits. Except for 18,000 feet MSL, Class E airspace has no defined vertical limit but rather it extends upward from either the surface or a designated altitude to the overlying or adjacent controlled airspace.

e. Types of Class E Airspace:

1. Surface area designated for an airport. When designated as a surface area for an airport, the airspace will be configured to contain all instrument procedures.

2. Extension to a surface area. There are Class E airspace areas that serve as extensions to Class B, Class C, and Class D surface areas designated for an airport. Such airspace provides controlled airspace to contain standard instrument approach procedures without imposing a communications requirement on pilots operating under VFR.

3. Airspace used for transition. There are Class E airspace areas beginning at either 700 or 1,200 feet AGL used to transition to/from the terminal or en route environment.

4. En Route Domestic Areas. There are Class E airspace areas that extend upward from a specified altitude and are en route domestic airspace areas that provide controlled airspace in those areas where there is a requirement to provide IFR en route ATC services but the Federal airway system is inadequate.

5. Federal Airways. The Federal airways are Class E airspace areas and, unless otherwise specified, extend upward from 1,200 feet to, but not including, 18,000 feet MSL. The colored airways are green, red, amber, and blue. The VOR airways are classified as Domestic, Alaskan, and Hawaiian.

6. Offshore Airspace Areas. There are Class E airspace areas that extend upward from a specified altitude to, but not including, 18,000 feet MSL and are designated as offshore airspace areas. These areas provide controlled airspace beyond 12 miles from the coast of the U.S. in those areas where there is a requirement to provide IFR en route ATC services and within which the U.S. is applying domestic procedures.

7. Unless designated at a lower altitude, Class E airspace begins at 14,500 feet MSL to, but not including, 18,000 feet MSL overlying: the 48 contiguous States including the waters within 12 miles from the coast of the 48 contiguous States; the District of Columbia; Alaska, including the waters within 12 miles from the coast of Alaska, and that airspace above FL 600; excluding the Alaska peninsula west of long. 160°00'00''W, and the airspace below 1,500 feet above the surface of the earth unless specifically so designated.

f. Separation for VFR Aircraft. No separation services are provided to VFR aircraft.

--------------------------------------------------------------------------
And it all works just fine, as long as your not a passenger caught up in delays around the 12 Class B airports. Then it's hell.

And more concrete is the biggest part of the answer to the delays. In Sydney we have water problems, population has trebled since the last dam was built, as far as I can recall, the new Denver is the only new major airport in 30 or so years, and I have no idea how many times movements have multiplied since than, it more than treble, much more.

Tootle pip!!

[CaptainMidnight]

Leadsled

Many thanks for posting that info. Interesting stuff.

[Terry Wesley-Smith]

Folks,


I have just become aware of this thread, and I have registered in order to respond with the facts.

As the CEO of the RAAA I found the thread interesting reading. I was particularly impressed by dragonflyhkg's comments, especially since the RAAA's position was and remains one of support for TCAS for all IFR passenger transport with 10 seats or more, despite Dick's opening salvo.

For the record, the Regulation Review Task Force of which Dick is a member recently made a recommendation to the SCC that TCAS and GPWS (types not specified) should be mandated for all passenger transport aircraft with 10 or more seats. The SCC asked the RAAA for its position. After an exhaustive consultation process with our members, I posted the formal RAAA response on the SCC website on 15 October.

Dick appears to have posted his initial post on this thread several hours before our position was published, and without any communication with this office on the subject.

For those who are interested in the facts, I will post our response to the SCC in full on our website www.raaa.com.au (http://www.raaa.com.au)

We support the use of TCAS, but buying TCAS without universal transponder carriage is a bit like being required to buy an expensive belt without a buckle. TCAS can not work unless conflicting aircraft have transponders, so it is not cost effective expenditure unless there is simultaneous fitment of transponders to all aircraft that can reasonably power them.

We do not want to unnecessarily restrict GA or to impose unnecessary costs. After all, we rely rather heavily on GA for our crews and many of our members are also GA pilots and aircraft owners. However, if the carriage of TCAS is so important to the safety of the travelling public that it should be mandated for all passenger transport aircraft with 10 or more seats, how could there possibly be any argument against the concurrent mandatory fitting of transponders to all potentially conflicting aircraft in the environment in which we operate?

That is the question that we (including the Regulation Review Task Force) as an aviation fraternity have to face.

Thanks for listening.

Regards,

Terry

[kimwestt]

Or could it be that the incident at Orange could have been avoided? This was the incident where a Rex aircraft was approaching from the east and an IFR Baron with a professional pilot was approaching from the west – both in cloud at the same time. When the Baron needed to do a missed approach it was heading straight into the IFR airline aircraft. The only way it could save the day was by illegally turning off the missed approach. Luckily there were no mountains there.

Dick - have you heard of Mount Canobolas???

[Atlas Shrugged]

Just for those who don't know Mount Canobolas, is not only the highest mountain in the Central West region of New South Wales, it is he highest point between Australia's Great Dividing Range and Africa (other than Mt. Zeil in the NT) and is an extinct sheild volcano.
http://www.canobolasmountaincabins.com.au/photos/scan9.jpg

[vans]

Dick’s opening post seems to indicate that the RAAA have had a longstanding opposition to the fitment of TCAS to passenger aircraft with 10 seats or greater. You seem to indicate that the RAAA have always supported the fitment.

Quote: “Especially since the RAAA's position was and remains one of support for TCAS for all IFR passenger transport with 10 seats or more”.

You then go on to qualify your remarks by indicating that you only support TCAS fitment provided everyone else capable of doing so, fits transponders.

Quote “We support the use of TCAS, but buying TCAS without universal transponder carriage is a bit like being required to buy an expensive belt without a buckle”.

It would seem to me that you do not support Dick’s position at all, which is for the 10 to 30 seat passenger aircraft to fit TCAS now, regardless of what other aircraft owners do.

Are you saying that the increased safety benefits arising from the fitment of TCAS to 10 and greater seat passenger aircraft, especially in E airspace, but also to a lesser extent in other airspace, is not worth the cost, despite the rest of the western world having already mandated this (according to Dick)?

Surely it is up to the RAAA to set the example here for their own sake, not demand that every aircraft capable of fitting transponders do so concurrently as a condition of you giving your passengers this additional safety benefit.

I hope I never see the day when your present position results in an accident.

[GaryGnu]

Vans,

You have to be careful when relying on Dick Smith as the basis for your rhetoric when you state despite the rest of the western world having already mandated this (according to Dick)?

As I posted here (http://www.pprune.org/forums/showpost.php?p=3117708&postcount=47) the ICAO requirement is for TCAS II in 19+ pax or MTOW 5700kgs + aircraft.

The US requirement is for >15,000kgs turbine powered aircraft to have Mode S and TCAS II (Ver 7). In the US 10-30 pax capacity aircraft require only TCAS I (i.e No Resolution Advisories).

The difference is subtle but it is there.