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ADS-B Mandate – ATCs Responsible for Deaths?

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ADS-B Mandate – ATCs Responsible for Deaths?

Old 28th Jan 2014, 11:45
  #201 (permalink)  
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The key issue (pardon the pun) with encrypted 1090ES is that it is not possible to securely issue and manage symmetric key material for all 15,000 odd aircraft on the VH register, let alone the rest of the world's civil aircraft. The bandwidth problem is pretty minor compared with this.
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Old 28th Jan 2014, 14:37
  #202 (permalink)  
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Yes and no. It is the broadcast string length that is the formost issue
Would you like to reconsider this statement, the FAA UAT system does not use the transponder, it is a separate transceiver, it is CDMA broadband, this is why encryption is not a problem.
Tootle pip!!
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Old 28th Jan 2014, 20:25
  #203 (permalink)  
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Here is a PDF from Lincoln Labs. Granted, it is a PowerPoint display. Hope this helps understand the basic workings of the ATM system.

edit- to add, PDF actually goes in depth on a number of issues.
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Old 28th Jan 2014, 23:03
  #204 (permalink)  
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Leadsled, what are you talking about CDMA broadband? ADS-B systems use the 1090 MHz Extended Squitter (1090ES) data link.

First off, the ADS message is limited to 56 bits. The issue has been, how much data from the ac can be braodcast in 56 bits. Note that currently S mode is 56 bits total.

Second, the bandwidth issue is well known, the FAA calls it congestion. Currently, ADSB uses 1090 Mhz, but the FAA is looking at using 978 Mhz below 18,000. Congestion is caused by the bandwidth being used up, and the system will drop aircraft.

Encription, again, well known issue..

"At the Black Hat and Defcon security conference this week in Las Vegas, two security researchers plan to give separate talks on the same troubling issue: By 2020, a new system known as Automated Dependent Surveillance-Broadcast or ADS-B will be required as the primary mode of aircraft tracking and control for commercial aircraft in the U.S.–earlier in other countries such as Australia. And both researchers say that ADS-B lacks both the encryption necessary to keep those communications private and the authentication necessary to prevent spoofed communications from mixing with real ones, potentially allowing hackers to fabricate messages and even entire aircraft with radio tools that are cheaper and more accessible than ever before.

“Anyone can technically transmit these messages,” says Andrei Costin, a Ph.D. candidate at the French security institute Eurecom who plans to give a talk called “Ghosts In The Air (Traffic)” at Black Hat. “It’s practically possible for a medium-technical savvy person to mount an attack and impersonate a plane that’s not there.”

Next-Gen Air Traffic Control Vulnerable To Hackers Spoofing Planes Out Of Thin Air
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Old 29th Jan 2014, 05:16
  #205 (permalink)  
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This is getting a long way off the thread.

....and to make it worse. Underfire doesn't even know what Leadsled is talking about
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Old 29th Jan 2014, 06:06
  #206 (permalink)  
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Indeed a long way.

So Dick, has your maintenance org sorted out the Service Letter yet? What did they say?

Did you give them a tune up for not sorting it out for you a few years ago?
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Old 29th Jan 2014, 06:44
  #207 (permalink)  
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This is getting a long way off the thread...
Hmm... though allowed to continue..

Seems to me some around here have an agenda.

Who makes the money from ADS-B ???

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Old 29th Jan 2014, 08:55
  #208 (permalink)  
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Who makes the money from ADS-B ???
Who saves money from ADS-B???

I know who will be paying for it.
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Old 29th Jan 2014, 21:10
  #209 (permalink)  
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Okay, I will bite...I am very aware that there are multiple systems...

I see nothing that shows there is enough bandwidth, as congestion is a well known issue.

I see absolutely nothing that shows any sort of encryption availablity in the data string. It is another well known issue.

So, rather than be cryptic and insultive, why not explain what you are talking about?
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Old 29th Jan 2014, 22:34
  #210 (permalink)  
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I'm not an expert, I've just read a bit. Others know more.

ADS-B systems use the 1090 MHz Extended Squitter (1090ES) data link.
ES not not universally used. The prime advocate of it is Australia. This is one of the reasons we have trouble getting ADS-B capable transponders.

Also your diagram shows ADS-B in, which Australia is not implementing.

The document that your diagrams come from is 14 years old and is predicated on data transfer speeds of 1 Mb/s. I'd be very surprised if there has not been significant improvement in these speeds which will increase the data capacity.

Congestion depends on the amount of traffic. Australia is the only country in the world that is universally mandating ADS-B for GA IFR aircraft. Other countries implementation varies. Some are by flight type (ie RPT) and some are above an altitude. Only Australia will require all IFR aircraft to use ADS-B.

ADS-B is another example of Australia thinking it has to be different than the rest of the world and the cost of this is borne by aircraft owners.
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Old 30th Jan 2014, 00:06
  #211 (permalink)  
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Here is a link that may provide a bit more perspective on the worldwide requirements of ADS-B. Please note that the document provided from the link is not from an aviation governing body, it is from an avionics supplier in Canada so I will accept that some of the information may be incorrect or incomplete in regards to various aviation jurisdiction requirements. So if it does feel free to point out any discrepancies, errors or omissions in it, I do feel however it should provide a good overview.


Here are a few exerts from the article (my bold) that I have included for those who do not wish to trawl through it:
Page 3:
NAV CANADA has thus far adopted exclusively the 1090ES (ADS-B Out) format, as have all other countries worldwide. The only exception is the USA with their “Dual-Link” ADS-B program.
For Canadians, aircraft with a 1090ES Transponder and approved interfaces will be compliant with US operating requirements; however those who frequent US skies under 18,000’ may also opt for a UAT.
Page 4:
The European mandate, in broad terms, requires 1090ES ADS-B Out with a Diversity Mode-S transponder.
As to the future, in July of 2012, Iridium Communications and NAV CANADA announced a planned joint venture. This new relationship promises to offer worldwide ADS-B-based air traffic surveillance services using the upcoming Iridium “Next” satellite network. These satellites begin launching in 2015 and will be completed in 2017.

The Iridium-NAV CANADA joint venture is called Aireon. It will add 1090ES ADS-B receivers to each of the 66 satellites (and backups) destined to form the Iridium “Next” constellation. The low-earth-orbiting Iridium satellites will offer worldwide coverage, including Polar Regions, and with the ADS-B payloads will provide complete visibility to all aircraft everywhere. This will help ANSP’s (air navigation service providers) increase efficiencies. This new capability will extend the benefits of current radar-based surveillance systems (which presently cover less than 10 percent of the world) to entire planet coverage. Aireon is expected to become operational in 2018.
Page 5:
1090ES ADS-B Out is the globally accepted system for ADS-B compliance.

One note here though - the FAA has uniquely adopted a “Dual-Link Architecture” for ADS-B compliance in the USA. This allows for a second equipment option.
Page 6:
The second or optional system is called a UAT. It is only applicable to aircraft operating in US airspace under 18,000 feet.
Note: a 1090ES ADS-B Out System is an absolute requirement for all aircraft that operate above 18,000 feet in US airspace and internationally.
aircraft with a 1090ES Transponder and approved interfaces will be compliant with US operating requirements; however those who frequent US skies under 18,000’ may also opt for a UAT.
Page 9:
The ES format carries much more data than the basic “short squit” Mode S version. In fact, some 49 individual parameters can be sent over the extended squitter, compared to three for Mode C and seven for basic non-extended Mode S. (Note: The 978 MHz UAT “Out” has the same basic data transmission elements as ES — however, it uses a different frequency in the radio spectrum to broadcast the information.)
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Old 30th Jan 2014, 04:06
  #212 (permalink)  
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Re your post #212, I have been in touch with Cessna Pacific and also Cessna in the USA for more than two-and-a-half years in relation to the ADS-B upgrade for my CJ-3.

A service letter is not actually a service bulletin. It appears the service bulletin from Cessna is necessary to give an avenue to modify the boxes in my aircraft so it is compliant.

The Cessna Tech Rep says the service bulletin is promised for the first quarter of this year – that “it’s coming”. When that service bulletin is available I will get a quote and then decide whether to spend the money on my aircraft or flog the aircraft back to the USA (I don’t use it that much) and fly my other aircraft more where you don’t have to pay Airservices a cent and you see fantastic scenery - or spend more time on my boat.

Most importantly, I have asked “the powers that be” if they would consider dispensations in line with what has been allowed in Canada. That is, the ADS-B airspace is flight level 350 to flight level 400 and dispensations will be considered into that airspace for non-ADS-B equipped aircraft depending on load factors.

I will advise what the outcome is!

By the way, have Airservices been able to save on staffing levels since the introduction of ADS-B? i.e. how many ATCs have been sacked?
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Old 30th Jan 2014, 05:18
  #213 (permalink)  
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Check Thrust, the bit you omitted in the (overall good) canadian reference is this:

At the time of writing we are not aware of any timetable for implementation of an ADS-B requirement
across Canadian Domestic Airspace by NAV CANADA.
I say again. Australia is the ONLY country in the world seeking to mandate ADS-B for GA IFR aircraft below about the mid flight levels.

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Old 30th Jan 2014, 05:27
  #214 (permalink)  
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Maybe, just maybe the radar coverage is different.......
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Old 30th Jan 2014, 05:30
  #215 (permalink)  
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how many ATCs have been sacked?
Dick, the question is provocative because AsA is almost certainly understaffed at the operational level while being dramatically overstaffed in the airconditioned offices of Canberra.

But the sentiment is 100% correct. If there is not a cost saving that can be measured and passed on to the users, there is no impulsion to mandate ADS-B other than generating overseas trips for management.

I think the question is sharper for me than you. In the Flight levels you will ultimately get the benefit of better traffic awareness and reduced separation. But at 6,000 ft OCTA I will get none of this benefit because I mix with non ADS-B VFR aircraft and non transponder RA(Aus) and glider traffic. So, why must I spend what might be $25,000 to upgrade. I can see absolutely zero safety or efficiency benefit. I will simply be spending nearly half the median Australian income for the benefit of AsA.
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Old 30th Jan 2014, 05:55
  #216 (permalink)  
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$25k?? Is that why you can afford outrageous call out fees??
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Old 30th Jan 2014, 06:03
  #217 (permalink)  
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Unfortunately, the FAA has decided to keep the message strings the same. There are many, many comittees working on trying to work with the string, add to it or modify it, to no avail for at least eh last 10 years.

(Akro, the diagram doesnt show ADSB-in, is shows the ac being able to see each other)

As far as UAT, it doesnt matter how it is transmitted, the message bit is the message bit. The freq bandwidth of the 1090 and 987 Mhz is the problem, there are only so many messages that you can put into each frequency, how fast you do it doesnt matter.

From last year:

From the Garmin site:

Even though it’s called a “Universal Access” transceiver, the 978 MHz UAT is actually less universal that the 1090 MHz “ES” transponder in terms of where it can fly and what airspace it can use.

For example, in its criteria for ADS-B “Out” compliance, the FAA will require 1090 ES transponders for aircraft operating higher than 18,000 ft MSL — while UAT is limited to aircraft that will operate no higher than 17,999 ft MSL.

So far, no country except the U.S. has accepted the 978 MHz UAT format for their ADS-B datalinks. (this may be why there is the issue)

Consequently, pilots who want to fly outside the U.S. — or operate at or above FL180 — will need the 1090 ES transponder for ADS-B “Out”. Since the FAA has decided to retain its Mode C and Mode S transponder requirements for flight in regulated airspace (to provide a secondary radar backup to ADS-B, as well as communicate with other aircraft that have traffic warning systems), the 1090 ES solution can satisfy both the ADS-B “Out” and functioning transponder requirement with the same piece of equipment.
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Old 30th Jan 2014, 06:13
  #218 (permalink)  
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This debate has been very educational when you get past the emotive issues.
There is no doubt in my mind that ADS is a wonderful safety tool, I just cant help wondering why we so desperately needed to do it ahead of the rest of the world, given our traffic density is really quite modest.
I have heard some fairly frightening figures $ wise that it cost Qantas link to comply with its Dash 8 fleet, a figure sure to reflect in the ticket price. Thats the rub really, we once had the RAAF who owned all the airspace and tolerated us civvies using bits and pieces of it, now it would seem Australian airspace is to become exclusively for the use them that can afford it. Of course RPT can spread the enormous costs across an awful lot of tickets, unfortunately GA dosnt have that luxury.
The added penalty CAsA has imposed on the whole industry by jumping the gun comes later down the track, when hapless owners who used Australian EO's try and sell their airplanes overseas, and find that CAsA's world best practice maintenance Reg's dont cut the mustard.
Check thrust's post #217 gives a tantalizing hint that technology is going to overtake the whole ADS debate or debacle whichever way you view it.
I have a very uncomfortable feeling that there will be a whole lot more aerial vehicles swanning about outback OZ nosar no details soon.
Would this have happened if "foster and promote" was in their brief??
.......and meanwhile across the Tasman.....

Last edited by thorn bird; 30th Jan 2014 at 06:28.
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Old 30th Jan 2014, 06:14
  #219 (permalink)  
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$25k?? Is that why you can afford outrageous call out fees??

But I plan ahead to use swipe cards or arrive in hours to try and save money to upgrade my steam panel to something halfway towards the RV-10.
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Old 30th Jan 2014, 10:26
  #220 (permalink)  
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Dick, SL + CAR 21M approval =

Have they not thought of that?
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