ADS-B and Air Traffic Control Systems - a Financial and Operational Disaster?
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ADS-B and Air Traffic Control Systems - a Financial and Operational Disaster?
I will preface this post by a disclaimer: I know SFA about ATC and the finer points of ADS - B, I have however been up to my neck in large expensive complex IT projects.
It started off at Ausfly as an innocent question over a beer to what I assume was a knowledgeable ADS - B person: "Dynon has announced a $US590 ADS -B conforming GPS for the USA, what chance it could be used here instead of a $5000+ certified GPS navigator for ADS - B?".
The answer to that, I was told was "Not a snowballs chance in hell". The discussion then turned to things technical. microseconds, thronomisters, and the like, about how ADS - B works with radar sets interrogation and suchlike.
"Couldn't ADS - B work with a reduced accuracy GPS with the integrity/accuracy bits set to low levels?" I asked innocently.
"Oh No!" chimed in an ATC person. "If we get ADS - B signals that aren't of the required accuracy, then we are going to have to put 25 mile buffers around the source aircraft to ensure separation". I thought I heard him say. According to him, one aircraft transmitting BS ADS - B signals will cuts a swathe through traffic as ATC has no way of knowing exactly where they are if the system relies on ADS - B alone! The discussion then turned to the vagaries of GPS and we all told our horror stories.
I think however I understood his point: if there are any dubious ADS-B returns in the system then the entire separation schemes, fuel cost savings from reduced separations, direct routings, etc., etc. breaks down. ATC can't just exclude an aircraft from its system and carry on as normal, because it can't be sure where that aircraft really is and thus can't guarantee separation. Of course this is a probability argument, it won't happen every time but you understand the drift.
I then thought of Thales and the new air traffic control system. I thought of the comments from knowledgeable people: "biggest crooks unhung". I thought of the recent disclosure in the Senate of apparent conflicts of interest in the project management. I thought of the CEO of AIrservices slightly unusual departure after only one term.
I thought of what I know about how contractors work on complex IT projects - how you bid low and then add on "variations" until the cost is triple the original budget. I thought of how the request for tender documents are always Five years out of date and behind todays technology and the window for profit that opens for the contractor.
Then I started to wonder: What are the chances of Thales delivering an ATC system that relies solely, or almost solely on ADS - B? What are the chances that any cost savings from the new system are reliant on a perfect implementation of ADS - B? Letting my mind wander, I asked what happens if an ADS - B aircraft has equipment failure in flight, or some butter fingered idiot stuffs up the setting on an ADS - B transponder?
Where is the resilience in the new ATC system? Does it rely almost solely on ADS - B? What is the backup? WHere is the redundancy? Is ATC effectively going to be blind if someone stuffs up ADS - B?
If I were a contractor, would I care if the new system was fragile as glass? No. Would I build in backups and resilience? No, those things are at extra cost. I would then generate more revenue and profit, building in the resilience and capacity to cope without ADS - B.
Such were my musings as I froze to death in my sleeping bag at Ausfly. Could I be forgiven for wondering if Australias new Air traffic control is going to be dangerously over reliant on a perfect implementation of a single technology - bearing in mind that no implementation is ever perfect?
It started off at Ausfly as an innocent question over a beer to what I assume was a knowledgeable ADS - B person: "Dynon has announced a $US590 ADS -B conforming GPS for the USA, what chance it could be used here instead of a $5000+ certified GPS navigator for ADS - B?".
The answer to that, I was told was "Not a snowballs chance in hell". The discussion then turned to things technical. microseconds, thronomisters, and the like, about how ADS - B works with radar sets interrogation and suchlike.
"Couldn't ADS - B work with a reduced accuracy GPS with the integrity/accuracy bits set to low levels?" I asked innocently.
"Oh No!" chimed in an ATC person. "If we get ADS - B signals that aren't of the required accuracy, then we are going to have to put 25 mile buffers around the source aircraft to ensure separation". I thought I heard him say. According to him, one aircraft transmitting BS ADS - B signals will cuts a swathe through traffic as ATC has no way of knowing exactly where they are if the system relies on ADS - B alone! The discussion then turned to the vagaries of GPS and we all told our horror stories.
I think however I understood his point: if there are any dubious ADS-B returns in the system then the entire separation schemes, fuel cost savings from reduced separations, direct routings, etc., etc. breaks down. ATC can't just exclude an aircraft from its system and carry on as normal, because it can't be sure where that aircraft really is and thus can't guarantee separation. Of course this is a probability argument, it won't happen every time but you understand the drift.
I then thought of Thales and the new air traffic control system. I thought of the comments from knowledgeable people: "biggest crooks unhung". I thought of the recent disclosure in the Senate of apparent conflicts of interest in the project management. I thought of the CEO of AIrservices slightly unusual departure after only one term.
I thought of what I know about how contractors work on complex IT projects - how you bid low and then add on "variations" until the cost is triple the original budget. I thought of how the request for tender documents are always Five years out of date and behind todays technology and the window for profit that opens for the contractor.
Then I started to wonder: What are the chances of Thales delivering an ATC system that relies solely, or almost solely on ADS - B? What are the chances that any cost savings from the new system are reliant on a perfect implementation of ADS - B? Letting my mind wander, I asked what happens if an ADS - B aircraft has equipment failure in flight, or some butter fingered idiot stuffs up the setting on an ADS - B transponder?
Where is the resilience in the new ATC system? Does it rely almost solely on ADS - B? What is the backup? WHere is the redundancy? Is ATC effectively going to be blind if someone stuffs up ADS - B?
If I were a contractor, would I care if the new system was fragile as glass? No. Would I build in backups and resilience? No, those things are at extra cost. I would then generate more revenue and profit, building in the resilience and capacity to cope without ADS - B.
Such were my musings as I froze to death in my sleeping bag at Ausfly. Could I be forgiven for wondering if Australias new Air traffic control is going to be dangerously over reliant on a perfect implementation of a single technology - bearing in mind that no implementation is ever perfect?
Last edited by Sunfish; 5th Sep 2015 at 22:25.
I think it were back in 2008 that the potential Terrorist miss-use of GPS via drone bombs were first mooted here on pprune. There were much derision of the possibility at the time.
It is now proven that the terrorists have GPS guided drone bombs and that there is no easy way as of yet to stop an inflight terrorist drone attack. The GPS signal either needs to be jammed or shut off. The Israeli's have proven the huge, and unsustainable, cost of defeating individual GPS guided terrorist drone attacks.
Until the GPS guided terrorist drone threat can be neutralised, any pilot/ATC reliance on ADS-B is a disaster waiting to happen.
.
It is now proven that the terrorists have GPS guided drone bombs and that there is no easy way as of yet to stop an inflight terrorist drone attack. The GPS signal either needs to be jammed or shut off. The Israeli's have proven the huge, and unsustainable, cost of defeating individual GPS guided terrorist drone attacks.
Until the GPS guided terrorist drone threat can be neutralised, any pilot/ATC reliance on ADS-B is a disaster waiting to happen.
.
Sunfish, radar use and coverage in the new system will be exactly the same as in the current system. Why would you think such a fundamental feature wouldn't be included with the specification for the new system? We managed to include it last time.....
The "entire separation schemes, fuel cost savings from reduced separations, direct routings, etc., etc" doesn't break down if there is an aircraft with broken ADS-B. We just have to resort to using procedural separation between that aircraft and any others it crosses paths with. A 1000ft works quite well. The miscreant aircraft with the dodgy ADS-B is the one who will get shafted if he can't be accommodated. Exactly as happens today.
You're confusing two systems. The first is the hardware and software, the second is the separation standards and controllers.
The new system will not be inherently more or less resilient than the current one to failure of radar or ADS-B equipment.
You've been listening to too many Dick Smith conspiracy theories.
The "entire separation schemes, fuel cost savings from reduced separations, direct routings, etc., etc" doesn't break down if there is an aircraft with broken ADS-B. We just have to resort to using procedural separation between that aircraft and any others it crosses paths with. A 1000ft works quite well. The miscreant aircraft with the dodgy ADS-B is the one who will get shafted if he can't be accommodated. Exactly as happens today.
You're confusing two systems. The first is the hardware and software, the second is the separation standards and controllers.
The new system will not be inherently more or less resilient than the current one to failure of radar or ADS-B equipment.
You've been listening to too many Dick Smith conspiracy theories.
Thread Starter
Penguin, I prefaced my post with a disclaimer. Dick Smith isn't the source of this issue, I dreamed it up myself.
What concerned me was the apparent fragility of ADS - B separation schemes and the expectation that ADS - B is supposed to work seamlessly with what are big complex IT systems that Thales will deliver. That, to me, is where the rubber meets the road.
What concerned me was the apparent fragility of ADS - B separation schemes and the expectation that ADS - B is supposed to work seamlessly with what are big complex IT systems that Thales will deliver. That, to me, is where the rubber meets the road.
Originally Posted by Le Pingouin
The "entire separation schemes, fuel cost savings from reduced separations, direct routings, etc., etc" doesn't break down if there is an aircraft with broken ADS-B. We just have to resort to using procedural separation between that aircraft and any others it crosses paths with. A 1000ft works quite well.
Given that the majority of navigation these days is by GPS, it can reasonably be assumed that the navigation source is the ADS-B source, however this is not always the case, particularly as the 'all IFR traffic' mandate approaches. It is quite possible to have one GPS driving the needles with another telling ATC where you are. If they disagree, which is trustworthy, and how does ATC know?
For systems that are supposedly "failsafe" in such a critical role, I would really like more security in a technology that can easily be spoofed or jammed.
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It is interesting that the ADSB mandate in the US requires that you keep your Mode C transponder.
I've been building GPS receivers for over 20 years (not rocket science as the magic bit is in the module or chip and I just do power supplies and data interfacing).
I do not understand the angst on the part of the authorities about GPS accuracy. Any decent modern GPS chip capable of being set up for aviation dynamics will be as accurate as any TSO'd expensive device. Currently in small quantity these sell for under A$20. RAIM is included but nowadays I haven't seen fewer than 8 sats even on the ground with buildings and trees around and more likely 10 to 12.
The US also allows the use of GPS modules for Experimentals which meet the requirements but aren't TSO'd, the Dynon and Garmin G20x are two examples of these.
There is also the Enigma device out of Melbourne. It will be interesting to see how that gets on with the authorities.
I've been building GPS receivers for over 20 years (not rocket science as the magic bit is in the module or chip and I just do power supplies and data interfacing).
I do not understand the angst on the part of the authorities about GPS accuracy. Any decent modern GPS chip capable of being set up for aviation dynamics will be as accurate as any TSO'd expensive device. Currently in small quantity these sell for under A$20. RAIM is included but nowadays I haven't seen fewer than 8 sats even on the ground with buildings and trees around and more likely 10 to 12.
The US also allows the use of GPS modules for Experimentals which meet the requirements but aren't TSO'd, the Dynon and Garmin G20x are two examples of these.
There is also the Enigma device out of Melbourne. It will be interesting to see how that gets on with the authorities.
KRviator...Fault Detection and Exclusion is the guarantee on integrity.
In the US, GA aircraft run on UAT, a data transmitter for their ADS-B. It is not a transponder. Therefore, it will not be seen by TCAS equipped aircraft. Hence mode C as a requirement.
Sunfish, plenty of electrons have been murdered in the name of ADS-B. Perhaps, a search of PPRUNE is in order?
In the US, GA aircraft run on UAT, a data transmitter for their ADS-B. It is not a transponder. Therefore, it will not be seen by TCAS equipped aircraft. Hence mode C as a requirement.
Sunfish, plenty of electrons have been murdered in the name of ADS-B. Perhaps, a search of PPRUNE is in order?
Sunfish, how is it any more fragile than radar? Aircraft suffer transponder failure in-flight today where there's no ADS-B coverage or they don't have it. We handle it.
Who do you think built the current system that is using ADS-B? Thales. It currently works quite seamlessly.
Who do you think built the current system that is using ADS-B? Thales. It currently works quite seamlessly.
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This is on the other ADSB thread, but is also relevant in this one.....
UNCLASSIFIED
Dear ACT RAPAC attendees - Please see information below from Airservices regarding ADS-B units as discussed at last week’s meeting.
A copy of the email below will be attached the Meeting Minutes.
Subject: ACT RAPAC 27AUG15 - Airservices Action response [SEC=UNCLASSIFIED]
As a follow up to ACT RAPAC, I have provided some information below on the action I received during my Airservices update on ADS-B (Agenda item 6.3): RAPAC Convenor, would like to understand the methodology behind why the Australian ADS-B mandate is limited to 1090-ES and why aircraft owners can’t simply install any ADS-B avionics that are currently available in the American market.
The following explains the Australian adoption of 1090MHz ES (Extended Squitter) and why UAT will not be adopted:
ADS-B in the USA
• The USA’s FAA has adopted a dual system using both 1090MHz and Universal Access Transceiver (UAT).
• The FAA has adopted 1090MHz for all flight levels, and UAT only for operations below 18,000 feet.
• UAT supports two-way links, and the FAA provides additional services on the uplink including TIS-B, ADS-R and FIS-B, for weather and aeronautical information.
• Dual 1090/UAT systems have not been adopted in Australia or any other country.
Why can't we use UAT in Australia?
• In Australia, air traffic infrastructure is funded by the aviation industry, including airlines and general aviation.
• No stakeholders are willing to fund the high cost of dual-link supporting infrastructure (combination of 1090MHz ES and UAT) and so there are no UAT based ADS-B ground stations in Australia.
• UAT equipment cannot be used in aircraft in Australia.
Will ADS-B provide weather information in Australia?
• There are no plans to uplink weather data on an ADS-B link in Australia.
• No stakeholders are willing to fund the necessary supporting infrastructure.
• Other methods of obtaining weather and operational relevant information is being widely adopted through smart device applications such as Ozrunways and Avplan, amongst others.
The following provides information on the purchase of ADS-B avionics:
Can I buy an ADS-B transponder and GPS from the USA? Will it work here?
• Yes, provided you buy only Mode S, Extended Squitter (1090ES) equipment that complies with the required Technical Standard Orders (TSOs).
• Remember that the USA provides TIS, TIS-B, FIS-B, ADS-R, and UAT services, which are not supported in Australia.
• Operation of UAT equipment is not frequency-licensed in Australia and therefore not permitted; and UAT transmissions cannot be detected by ATC.
• Do not forget that equipment purchased in the USA must be installed in an Australian aircraft by a licensed and appropriately rated LAME and that CAR 21M design approval may be required.
• In many cases, owners find that the expected savings from purchasing overseas are outweighed by the added complexity of purchasing equipment and arranging approvals and installation separately.
Additional information:
The following is a link to the Airservices ADS-B FAQs which may be of interest to ACT RAPAC members:
http://www.airservicesaustralia.com/...1-11-MAY15.pdf
Aircraft operators are also reminded that they can contact the Airservices ADS-B hotline on 1800 844 487 should they have additional questions.
Kind Regards,
Aviation Relations Manager
Corporate and Industry Affairs
25 Constitution Ave, Canberra ACT 2601
Dear ACT RAPAC attendees - Please see information below from Airservices regarding ADS-B units as discussed at last week’s meeting.
A copy of the email below will be attached the Meeting Minutes.
Subject: ACT RAPAC 27AUG15 - Airservices Action response [SEC=UNCLASSIFIED]
As a follow up to ACT RAPAC, I have provided some information below on the action I received during my Airservices update on ADS-B (Agenda item 6.3): RAPAC Convenor, would like to understand the methodology behind why the Australian ADS-B mandate is limited to 1090-ES and why aircraft owners can’t simply install any ADS-B avionics that are currently available in the American market.
The following explains the Australian adoption of 1090MHz ES (Extended Squitter) and why UAT will not be adopted:
ADS-B in the USA
• The USA’s FAA has adopted a dual system using both 1090MHz and Universal Access Transceiver (UAT).
• The FAA has adopted 1090MHz for all flight levels, and UAT only for operations below 18,000 feet.
• UAT supports two-way links, and the FAA provides additional services on the uplink including TIS-B, ADS-R and FIS-B, for weather and aeronautical information.
• Dual 1090/UAT systems have not been adopted in Australia or any other country.
Why can't we use UAT in Australia?
• In Australia, air traffic infrastructure is funded by the aviation industry, including airlines and general aviation.
• No stakeholders are willing to fund the high cost of dual-link supporting infrastructure (combination of 1090MHz ES and UAT) and so there are no UAT based ADS-B ground stations in Australia.
• UAT equipment cannot be used in aircraft in Australia.
Will ADS-B provide weather information in Australia?
• There are no plans to uplink weather data on an ADS-B link in Australia.
• No stakeholders are willing to fund the necessary supporting infrastructure.
• Other methods of obtaining weather and operational relevant information is being widely adopted through smart device applications such as Ozrunways and Avplan, amongst others.
The following provides information on the purchase of ADS-B avionics:
Can I buy an ADS-B transponder and GPS from the USA? Will it work here?
• Yes, provided you buy only Mode S, Extended Squitter (1090ES) equipment that complies with the required Technical Standard Orders (TSOs).
• Remember that the USA provides TIS, TIS-B, FIS-B, ADS-R, and UAT services, which are not supported in Australia.
• Operation of UAT equipment is not frequency-licensed in Australia and therefore not permitted; and UAT transmissions cannot be detected by ATC.
• Do not forget that equipment purchased in the USA must be installed in an Australian aircraft by a licensed and appropriately rated LAME and that CAR 21M design approval may be required.
• In many cases, owners find that the expected savings from purchasing overseas are outweighed by the added complexity of purchasing equipment and arranging approvals and installation separately.
Additional information:
The following is a link to the Airservices ADS-B FAQs which may be of interest to ACT RAPAC members:
http://www.airservicesaustralia.com/...1-11-MAY15.pdf
Aircraft operators are also reminded that they can contact the Airservices ADS-B hotline on 1800 844 487 should they have additional questions.
Kind Regards,
Aviation Relations Manager
Corporate and Industry Affairs
25 Constitution Ave, Canberra ACT 2601
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Sunny,
Did you stop to talk to Hans at Integra?
Probably would not have had a chance to talk to the unicom guys, but between those two groups your answers would have been sorted.
Heck the ASA folk were there too.
Did you stop to talk to Hans at Integra?
Probably would not have had a chance to talk to the unicom guys, but between those two groups your answers would have been sorted.
Heck the ASA folk were there too.
Cost of ADSB for GA
So, can anyone advise what it will cost to put an ADSB system in a SE aeroplane which is already IFR equipped and certified? ballpark figure???
thanks
Seabreeze?
thanks
Seabreeze?
Seabreeze
This has been covered many times. Here are my rough numbers:
ADS-B TXP $3,500k (say)
New grayscale encoder $1k
Engineering orders (say 2) $700
New TXP antennae $500
Installation (est) $3k
Total: $8,700
if your GPS is NOT WAAAS, add
secondhand Garmin 430W AUD$10,000 (if you are lucky)
New GTN 650 maybe AUD$20,000
Plus new antennae wiring (required) plus engineering order plus rack re-layout & installation, say $5k
Pretty much backs up Leadie's numbers
This has been covered many times. Here are my rough numbers:
ADS-B TXP $3,500k (say)
New grayscale encoder $1k
Engineering orders (say 2) $700
New TXP antennae $500
Installation (est) $3k
Total: $8,700
if your GPS is NOT WAAAS, add
secondhand Garmin 430W AUD$10,000 (if you are lucky)
New GTN 650 maybe AUD$20,000
Plus new antennae wiring (required) plus engineering order plus rack re-layout & installation, say $5k
Pretty much backs up Leadie's numbers
Last edited by Old Akro; 8th Sep 2015 at 00:45.
"Oh No!" chimed in an ATC person. "If we get ADS - B signals that aren't of the required accuracy, then we are going to have to put 25 mile buffers around the source aircraft to ensure separation".
Australia is THE ONLY COUNTRY IN THE WORLD mandating ADS-B for ALL IFR aircraft at ALL levels in ALL airspace types.
BUT, ADS-B is only mandated for IFR aircraft, but not VFR.
So, where are the benefits to GA? The ATC person is effectively saying that I will get no benefit from the reduced separation requirements of ADS-B.
I have had 3 near misses that have frightened me. In each case I was IFR on an IFR plan and the other aircraft was a NO DETAILS VFR flight. One of these was at 10,000ft and one was while I was in cloud. ADS-B will not improve safety in any of these instances.
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NextGen heading for a $40B Failure with severely flawed ADS
FAA's NextGen is heading straight for a massive $40B failure. A big part of that problem is a severely distorted, misguided, ADS-B concept (far from the original ADS-B intent), that is now overspecified in key aspects (e.g., overspecified NIC and NAC), while failing in other critical areas... (all vehicles need to see each other directly, even UAVs - not via using ADS-R [ADS ridiculous] or UAT [Useless Aircraft Transponder]). ATC advocates claiming that ADS-B [in the US] needs WAAS level of accuracy and integrity are simply wrong. That's because FAA has NextGen's balance for C-N-S completely mis-designed and wrong, incorrectly assuming that ATS's future is based on and depends on essentially using PastGen's 1940s "pseudo radar" vector concept. FAA's ADS-B is simply not going to work, at any cost (which is still substantial, and well over $5K for any reasonable installation - don't believe one word of the commercial PR blitz now being put out by the ADS "junk dealers" and avionics shops for $1999 units, that aren't installed, and aren't even anywhere on the path to future [real] ATS modernization needs).
Instead, FAA should scrap 91.225/91.227, allow for the airline delay of ADS equipage to at least 2025 (which FAA has all but already agreed), and focus on design of a proper NextGen, based on RNP based trajectory [state vector] exchanges [with any data link], and use of a redefined ADS-A, ADS-B, and ADS-C criteria, that are more relevant, practical, affordable, and not massively overspecified, as the present absurd TSO and RTCA specs written by the avionics manufacturers, largely to cater to seriously misstated FAA (false) requirements, while unnecessarily driving up avionics equipment complexity, cost, and ultimately profit.
Instead, FAA should scrap 91.225/91.227, allow for the airline delay of ADS equipage to at least 2025 (which FAA has all but already agreed), and focus on design of a proper NextGen, based on RNP based trajectory [state vector] exchanges [with any data link], and use of a redefined ADS-A, ADS-B, and ADS-C criteria, that are more relevant, practical, affordable, and not massively overspecified, as the present absurd TSO and RTCA specs written by the avionics manufacturers, largely to cater to seriously misstated FAA (false) requirements, while unnecessarily driving up avionics equipment complexity, cost, and ultimately profit.
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When considering about what ADSB can or cannot do and when, this year a number of terrestrial navaids were turned off and in May next year some 200 terrestrial navaids will be turned of in Australia.
Is this jumping the gun?
Is this jumping the gun?
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Caution is warranted for any Navaid shutdowns
"Is this jumping the gun?" Likely for most cases, YES - it is jumping the gun.
The human factors interfaces with most (if not all current) low end GA RNAV systems (and many RNAV systems even in BizJets) is still marginal, if not even awful, making them difficult and vulnerable for any serious IFR IMC use. Until and unless these RNAV systems (e.g., GPSs) have their HF user interfaces substantially improved in later generations for serious IFR flying, except for air carrier aviation that uses modern exceptionally good FMSs with RNP, and aids like ILS and GLS, ...it is a very risky proposition (safety wise) to shut down any significant number of classic Navaid facilities that are currently being used by low end GA.
That's why it is so critical that GA finally get access to low cost high quality RNP based FMS like navigators soon (driven by a GNSS + low cost inertial component engine), and be able to dump this current generation of very difficult to use GPS panel mount navigators (WAAS and LPV are virtually useless), that no amount of initial or recurrent training can ever adequately satisfy, ...short of a pilot staying current by having to fly with them for hours every every single day.
The human factors interfaces with most (if not all current) low end GA RNAV systems (and many RNAV systems even in BizJets) is still marginal, if not even awful, making them difficult and vulnerable for any serious IFR IMC use. Until and unless these RNAV systems (e.g., GPSs) have their HF user interfaces substantially improved in later generations for serious IFR flying, except for air carrier aviation that uses modern exceptionally good FMSs with RNP, and aids like ILS and GLS, ...it is a very risky proposition (safety wise) to shut down any significant number of classic Navaid facilities that are currently being used by low end GA.
That's why it is so critical that GA finally get access to low cost high quality RNP based FMS like navigators soon (driven by a GNSS + low cost inertial component engine), and be able to dump this current generation of very difficult to use GPS panel mount navigators (WAAS and LPV are virtually useless), that no amount of initial or recurrent training can ever adequately satisfy, ...short of a pilot staying current by having to fly with them for hours every every single day.