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What's Up with ADS-B?

M

mcattell

Well Known Member
Per the FAA website ADS-B has been turned on in Florida.

"Pilots flying in aircraft equipped with Automatic Dependent Surveillance-Broadcast (ADS-B) avionics in South Florida now receive free traffic and weather information on their cockpit displays. This marks the first time that pilots are able see the same traffic information that?s seen by air traffic controllers."

See the full story here: http://www.faa.gov/news/updates/?newsId=56970

So where can you buy equipment to actually use ADS-B? It doesn't look like any Garmin transponders support it yet. I bought a GTX-330 with TIS but that only will work around major cities. I heard that model transponder may be upgradable to ADS-B in the future but there isn't anything yet. So for us GA guys does anyone know if there's equipment available for ADS-B yet?
 
This company, Navworx is offering an ADS-B box for $1,495.00. They offer a portable (PADS-600) and "hard-mount" (ADS-600) version.


Here is a slide deck from their site: http://navworx.com/docs/ADSBSlides.pdf

Also, it seems that the decommissioning of radar sites with TIS capabilities, does not mean a Mode-S transponder will become useless. While the new FAA radars many not have TIS capability, ADS-B Ground Based Transmitters (GBT) will broadcast TIS and FIS.
 
The only way you can receive the TIS-B portions of ADS-B right now is over the Universal Access Transponder (UAT) part of ADS-B, which is what the FAA commissioned in Florida.

As RV10Rob rightly points out, the only company making "certified" UATs right now is Garmin, and you'll have to invest in a display of some sort to use with the GDL-90 to see the traffic from either the ground-based TIS-B system or other aircraft equipped with UAT.

UAT is a bidirectional link, so it would be interesting to see how well a receive-only unit like the Navworx box would work.

I worked on ADS-B for a few years in its R&D phase, it's nice to see that some form of it is finally making it into the real world...

Dave
 
We're all guessing at this point, but I can't see the feds giving away weather data that is described in the NAVWORX slides - this is essentially what XM and WSI charge a lot of money for, and they will howl about the potential loss in recenue. I suppose part of it will depend on who is running the FAA after Jan 2009.

As others point out, the FIS-B recievers are going to be expensive, whereas XM will remain (comparitively) cheap.

TODR
 
Garmin 330

mcattell said:
I heard that model transponder [GTX 330] may be upgradable to ADS-B in the future but there isn't anything yet.
Click to expand...

I called Garmin about 6 mos ago and asked if there was any plan to "upgrade" the 330 (I also have one and love it). The response was "Nope" {in a friendly tone:)}.
 
the_other_dougreeves said:
As others point out, the FIS-B recievers are going to be expensive, whereas XM will remain (comparitively) cheap.

TODR
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Hmm, let see a "certified" GDL 69A -XM Weather only receiver is $4,795 PLUS over $700 per year in subscription charges. A TIS/FIS GDL-90 which includes a IFR certified (TSO-C145a) WAAS GPS is $6,895 and no subscription. XM gives you only weather whereas ADS-B would provide weather an traffic. If you add the cost of in cockpit traffic, ADS-B is considerable more cost effective than XM--and that's just certified hardware. Non certified hardware should be even less expensive.

The safety argument will compel the FAA to offer weather via FIS and unless some unscruplous politician like ex Senator Rick Santorum R-PA attempts to gets in bed with XM, it will have a short window of opportunity.
 
w1curtis said:
The safety argument will compel the FAA to offer weather via FIS and unless some unscruplous politician like ex Senator Rick Santorum R-PA attempts to gets in bed with XM, it will have a short window of opportunity.
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Surely you jest ... our elected officials would never do such a thing! ... unless there was something in it for them ... ;)

I think this is the biggest threat to the acceptance and adoption of ADS-B - stability. It's not clear if the rest of the world will go with UAT or 1090ES - it looks like Europe is leaning towards 1090ES - and the issue of what data will be provided on FIS is going to be interesting. I'm getting the popcorn ready to watch the fight....

Don't get me wrong, it would be nice to get the data and not have to pay XM monthly (well, quarterly), but until it's clear that the data link works and won't get turned off, I can't see a reason to install expensive ADS-B goodies.

The other unresolved issues are (1) when will Mode C be phased out / ADS-B be required, (2) spoofability of ADS-B messages and (3) robustness of ADS-B (i.e., resistance to jamming, intentional or unintentional overloading).

BDR
 
w1curtis said:
The safety argument will compel the FAA to offer weather via FIS ...
Click to expand...

the_other_dougreeves said:
...it would be nice to get the data and not have to pay XM monthly (well, quarterly...
Click to expand...

Before you get too excited about free weather, read the FAA's fine print on the ADS-B program. The government is buying a service, not the hardware itself - ITT will own/operate the system and provide data to ATC. I'm not holding my breath for free FIS-B weather that matches XM Weather, it wouldn't surprise me to see the FAA allow ITT to charge for some weather products.

Mode C will probably not go away completely, since the FAA's plan as of now is to retain some secondary (i.e., transponder-based) radar capability as a backup in case of an ADS-B outage.

Dave
 
the_other_dougreeves said:
..The other unresolved issues are (1) when will Mode C be phased out / ADS-B be required, (2) spoofability of ADS-B messages and (3) robustness of ADS-B (i.e., resistance to jamming, intentional or unintentional overloading).

BDR
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I remember when I was in college back in the late 80s when GPS had only a few operational satellites and service was only part time. The EXACT same questions were being asked by many. Even more recently the same questions came up regarding WAAS. With any technology, there will always be the "doom and gloomers" but I hope we don't need a catastrophe like KAL 007 to do for ADS-B what KAL 007 did for GPS.

Europe seems to always go the complicated route so I would not worry about what standard they go with--anyone remember Galileo? Talk about a horse designed by committee. I think they were looking to go with VHF Data Link (VDL) Mode 4. FAA has committed to support UAT and 1090ES. Not as sophisticated and VDL but good enough.

gvgoff99 said:
I called Garmin about 6 mos ago and asked if there was any plan to "upgrade" the 330 (I also have one and love it). The response was "Nope" {in a friendly tone}.
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This was the press release by Garmin last year on upgrading GTX33/330 to 1090ES. http://www8.garmin.com/pressroom/aviation/072407.html
 
ADS-B currently is in the NPRM stage for Out functionality. My opinion (see http://stopads-b.org/ADS.htm) is that ADS-B Out offers little to nothing for most GA folks and may well cost a lot.

If you want most of the ADS-B In functionality you can get it with XM weather and Zaon like systems.

Most GA folks seem to ignore this issue but when they are faced with a $8000 plus bill in 12 years or so to comply they will wonder what happened. Fight it now or pay later.
 
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w1curtis said:
I remember when I was in college back in the late 80s when GPS had only a few operational satellites and service was only part time. The EXACT same questions were being asked by many. Even more recently the same questions came up regarding WAAS. With any technology, there will always be the "doom and gloomers" but I hope we don't need a catastrophe like KAL 007 to do for ADS-B what KAL 007 did for GPS.
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I guess you'll have to put be down as one of the "gloom and doom"ers, particularly when considering the Feds' track record of finishing projects on time and within budget (no offense to any of the Feds present on VAF unless you were behind the FSS "upgrades", and if you were, let's talk). WAAS was supposed to cost $600 mil and cost over $3 bil. Where is the already paid-for Mode-S TIS going? You get the idea.

We have to ask questions about the cost, robustness and security of ADS-B; ignoring problems isn't going to make them go away. We're proposing to replace a mature, functioning system that is well understood with something new. We need to evaluate the new system before we adopt it. Looking at the NPRM, one gets the idea that we're committing to a system that isn't well thought out and certainly isn't complete.

ADS-B is a really neat idea. However, as proposed, it all runs on GPS. We know GPS can be spoofed and jammed surprisingly easily. Imagine if instead of a shining a laser at people, some jerk puts up a GPS jammer they got for $20. Oops, ADS-B doesn't work within 5 miles of JFK and EWR anymore, sorry. Will ADS-B use (require?) the new L2 / L5 GPS signals?

Cost is another issue. A Mode C XPDR and antenna are less than $2k. What will ADS-B cost? How long will the Mode C/S to ADS-B transition period be? Will there be a "ADS-B Veil" like the existing Mode-C veils? Is a TSO required? Yes, these are big questions, but they need to be answered.

I don't think you can compare the introduction of GPS to the replacement of Mode C with ADS-B. GPS was designed for and owned by DoD; it made no guarantees to civilian users. It wasn't until everyone realized that GPS had already become a public service that SA was turned off and other improvements made (e.g., new L2C and L5 signals). But at the time, if GPS stopped working, well, too bad - DoD told you not to expect it to work all the time and it was not approved as a primary nav reference. But the biggest thing is that nobody was being required to convert to GPS, whereas ADS-B will be a mandate. The ground-based navaids (with the exception of many NDBs) are still there, at least for the moment.

ADS-B has the potential to be the best thing since sliced bread (well ... almost ... maybe pre-ground coffee), but it also has the potential to be an expensive boondoggle. I'm just asking the FAA to explain how this is all going to work before we commit (or are committed) to it.

TODR

PS - Yes, I'm grumpy today. Sorry to take it out on ADS-B.
 
Well, to paraphrase the old general, ?any [weapon] system that comes in on time and under budget, can?t be much of a weapon.?

I?ll say it again, unfortunately it has primarily taken tragedy to cause the luddites to get of the stump and adopt new [proven] technology in aviation.

-In 1983 Korean Air Lines flight 007 with its INS wandered off course over Russia and was shot down. 269 passengers loss their lives in this shoot down. President Reagan offers up DOD's GPS ?C? code to the world for free use. While the DOD has always reserved the right to ?shut if off? even in the wake of 9/11 and both Iraq wars, they have never done so.

-In 1986 the untimely meeting of a Piper Cherokee Archer II and an AeroMexico DC-9 over Cerritos, California resulted in the death of 82 people in the air and on the ground and Congress forcing the FAA to mandate Mode C in certain areas.

-The loss of Scott Crossfield in a weather related accident while under positive ATC did not prompt any urgent mandates by the government, however lack of ATC provided weather was specifically cited by the NTSB in their final report on his accident where they stated ?the air traffic controller's failure to provide adverse weather avoidance assistance, as required by Federal Aviation Administration directives.?

http://www.avweb.com/avwebflash/news/NTSBLackOfWeatherInfoDoomedScottCrossfield_196245-1.html

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20060501X00494&key=1

One last note, while it is relatively easy to ?locally? jam GPS, it would require MIL spec hardware and power levels to ?generally? jam it over a wide enough area to affect aircraft navigation. Those high power levels would cause the jammers themselves to become an easy target for the Feds. So yes, you could jam GPS but it would be so easy to find you, it would be stupid to do so.
 
w1curtis said:
-The loss of Scott Crossfield in a weather related accident while under positive ATC did not prompt any urgent mandates by the government, however lack of ATC provided weather was specifically cited by the NTSB in their final report on his accident where they stated ?the air traffic controller's failure to provide adverse weather avoidance assistance, as required by Federal Aviation Administration directives.?
Click to expand...

What a convenient scapegoat. Unless I am mistaken, a few minutes looking at available radar, getting a briefing or heaven forbid...looking out the window would have prevented that pilot error death.
 
Ron Lee said:
w1curtis said:
-The loss of Scott Crossfield in a weather related accident while under positive ATC did not prompt any urgent mandates by the government, however lack of ATC provided weather was specifically cited by the NTSB in their final report on his accident where they stated ?the air traffic controller's failure to provide adverse weather avoidance assistance, as required by Federal Aviation Administration directives.?
Click to expand...

What a convenient scapegoat. Unless I am mistaken, a few minutes looking at available radar, getting a briefing or heaven forbid...looking out the window would have prevented that pilot error death.
Click to expand...
The other day I was talking to a friend who retired from NASA a few years ago. While there he worked on the AGATE program and a few others. When I was telling him about the Dynon EFIS w/ autopilot and 496 w/ weather in my VFR ship he told me that when they (NASA) was proposing weather in the cockpit the FAA bulked at the idea. Apparently at the time the FAA insisted that VFR and IFR pilots would make bad decisions based on in cockpit weather and that the fatality rate would go up. They argued that if a pilot took off with a weather forecast that was at best two hours old, and they knew it was old, they would be safer.

When I heard this, I really started wonder about what the goals of the FAA administration really are.
 
w1curtis said:
Well, to paraphrase the old general, “any [weapon] system that comes in on time and under budget, can’t be much of a weapon.”
Click to expand...
That's exactly my point. If the Feds say it will cost $3bil, there's a good chance it will be $10bil - there's not all that much accountability when taxpayer money is being spent.

w1curtis said:
So yes, you could jam GPS but it would be so easy to find you, it would be stupid to do so.
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Nobody said that the idiots who shine lasers into cockpits were rocket scientists. However, they do manage to put planes at risk and there seems to be no shortage of these morons. People can be stupid and lethal while they think they're just playing a simple prank (although methinks that most of the laser pointer reports state "alcohol may have been a factor"). This says nothing of a determined enemy who wishes to "blind" ATC as part of a larger attack. The current system is just not vulnerable in this fashion.

As for finding them, well, there's been off-and-on "pirate radio" ATC in the SoCal area for years; I've never heard of any of them being caught, but maybe they have. We never used to find ham radio jammers anywhere I lived. Backyard laser pointer idiots aren't always found (although one recently painted a police helo repeatedly ... like I said, not rocket scientists). Are we going to have mobile GPS jammer DF units and trained teams parked at every TRACON, waiting to roll? Not likely.

The system needs to be robust and secure. One guy with a laser pointer can blind a single aircraft, but one guy with a GPS jammer (or "pseudolite" transmitter) could disrupt ADS-B for all aircraft along a critical part of a approach SID - it don't need to affect navigation over a wide area. What if it happens when the whole area is LIFR?

Are the existing primary and secondary radars (e.g., ASR-11) going to be maintained? I'm sure that someone is going to propose shutting some of them down and using that savings to offset overall project costs.

The new system has a lot of potnetial is not going to be completly risk-free, but we need a good system, since we're going to be using it for probably 30+ years. One possible path is to wait for the GPS modernization signals (L2C, L5) to come on-line before relying on ADS-B, as they should provide some more jam resistance (although not as much as the new mil only M-code). It is going to take a while, though, to get the GPS sats upgraded (only 6 are in the current constellation).

TODR
 
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Part of what makes the GDL-90 so expensive is that it includes a full blown TSO-C146a WAAS GPS engine. I would think that at some point Garmin, navworx (and other vendors) will offer a box that would output the same information as the GDL-90 but without the integral WAAS GPS since it would be connected to a GNS-430w or other on board GPS. I know at least one RV-10 builder that is installing a GDL-90. I"m anxious to see what services they receive on it. Since he is on the east coast, I think it may be worth it.

ADS-B OUT is a very low expectation requirement. A Garmin GTX-33/330 upgraded to 1090ES would satisfy this requirement, and you have until 2020 to comply. That's an eternity for electronics. http://www8.garmin.com/pressroom/aviation/072407.html

I think by then however there will be varying less expensive options for compliance that will be no more expensive than today's Mode C transponder--assuming you already have an onboard GPS. Before the Cerritos tradedgy, there were many that balked about equiping their planes with Mode C with no immediate benefit to them.

http://www8.garmin.com/pressroom/aviation/073108.html
Capstone proved that the technology works. Any system can be improved upon but at some point you have to realize that you will never get to perfect and "good enough" is good enough.

Here is how the Air Force deals with jamming devices in Iraq: http://www.space.com/news/gps_iraq_030325.html
 
You assume too much to make this possible mandate inexpensive. My guess is that the GPS engine (internal or external) must have integrity. This rules out a handheld GPS. So add how many thousands for a GNS 430?

I also do not have the transponder you mentioned so that does not help. There is no assurance that any avionics will drop substantially between now and 2020.

There has been no proof that ADS-B Out offers any safety benefit to the GA community. Capstone does not prove it.
 
William, I already reviewed this issue and you can see my assessment here:

http://stopads-b.org/ADS.htm

The current ADS-B NPRM/proposed mandate is OUT functionality only. It provides little to no benefit to the GA community. Read my assessment above.

ADS-B has been hyped incorrectly to the GA community for years.

I will make the prognostication that the ADS-B Out mandate will decrease safety since people who stay below 10,000' may largely not equip. IF...(we shall see) the FAA decommissions radar that supports Mode C then we will have aircraft not tracked. I use flight following. I fly mostly above 10,000' but do get below 10,000' to land. If ATC cannot see Mode C equipped aircraft they cannot point them out to me or jets carrying lots of people. Can you say Cerritos?

You can call me a luddite or heretic or naysayer but I have shown that ADS-B Out offers little to no benefit to the GA community.
 
1090 ES on GTX-330

Looks like Garmin has put a price ($1,200) and a date (Q3 '08) on GTX-330 1090 ES functionality.

http://www.astra.aero/downloads/ABIT/ABIT12_Garmin_June08.pdf
Slide 9 is interesting for those that believe that Capstone was ineffective.

Basically if you have a GNS430/480/530 and a GTX-330 + $1,200 you will be able to comply with ADS-B out. The list price for a new GTX-330 ES will be $5,995. The remote mount GTX-33 ES will list for $5,195. I'm not sure what, if any, premium this represents over the standard GTX-330.

I think I may go ahead and add that top antenna to be prepared for whatever comes.
 
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