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todehnal
05-31-2010, 12:54 PM
Well, it looks like ADS-B is here to stay. So, I guess we may as well try to take advantage of the services that will come with it; mainly TIS/B and FIS/B. The idea of getting free traffic and weather in the cockpit is inviting, but what is out there that will display it? Any handheld moving maps make the grade, like Anywhere Maps duo or Garmin's 696? I'm not into the expensive 430/530 stuff, but I wouldn't mind going mode S on the transponder, if I needed to.

This is probably a premature question, since the avionics manufacturers are probably scratching their heads about now, trying to figure out some marketable solutions themselves.

Comments please!

Tom

N130WN
06-12-2010, 07:04 AM
I ordered a ads600-b (http://navworx.com/ads600-b.asp) box at SNF from NavWorx. I plan to use it for traffic and weather (and TFR?) on a dual screen AFS setup. It's a little scary being on the bleeding edge of this stuff, but sometime you just gotta just jump in.

There was another vendor sharing the booth with navworx that was selling a HP PDA setup to work with the NavWorx product. It might meet your needs. It seemed to work alright, but I didn't look at it close.

Rainier Lamers
06-12-2010, 02:11 PM
I ordered a ads600-b (http://navworx.com/ads600-b.asp) box at SNF from NavWorx. I plan to use it for traffic and weather (and TFR?) on a dual screen AFS setup. It's a little scary being on the bleeding edge of this stuff, but sometime you just gotta just jump in.

There was another vendor sharing the booth with navworx that was selling a HP PDA setup to work with the NavWorx product. It might meet your needs. It seemed to work alright, but I didn't look at it close.

Yup.

Navworx - good choice. Busy integrating now...

ADS-B is indeed the future.

Rainier
CEO MGL Avionics

frankh
06-12-2010, 03:30 PM
So we can get the full ADS-b feature set for $1500?..Assuming a home integration option.

Doesn't sound too bad and prices will in theory come down?

Frank

frankh
06-12-2010, 03:35 PM
$1500 for just the receive unti..the transmit deal is $2500..Ouch

Mike D
06-12-2010, 09:17 PM
Disclaimer: I am not an EE not do I even pretend to know how to build electronics. So take my comments with this in mind.:)

It seems that building a ADS-B receiver is not too hard for someone much more technically knowledgeable than myself.

I could never build this but, it seems there is a whole group on home brewers out there building home based ADS-B receivers to watch aircraft in their spare time. From reading what has been written on these sites, it seems that you would have to receive the 1090 MHz ADS-B signals, convert the signals, and send them to a display of some sort (GRT, MGL, 496??) It appears the TIS like data is not too much of an issue, but the weather takes slightly more doing.

Some have built receivers from scratch and some in Europe have converted store bought DBS satellite receivers.

Here is a example of a DIY (experimental) ADS-B receiver
http://rxcontrol.free.fr/PicADSB/index.html

Here is a site that links several home based ADS-B receivers and maps the aircraft.
http://www.flightradar24.com/

So I agree several grand to have a receiver seems to be a little high. But there may be some FCC red tape on the ADS-B out part.

Seems like a project for Byonics! :D

az_gila
06-13-2010, 01:43 AM
....

So I agree several grand to have a receiver seems to be a little high. But there may be some FCC red tape on the ADS-B out part.

Seems like a project for Byonics! :D

...is more like FAA red tape. If I understand it corrrectly, the data source for the ADS-B Out has to be certified and to a WAAS standard - apparently to be more drop out free than a standard GPS source.

The FAA did this in the TSO specifications...

Thermos
06-13-2010, 05:34 AM
...the data source for the ADS-B Out has to be certified and to a WAAS standard - apparently to be more drop out free than a standard GPS source.

That's absolutely right. For ADS-B Out, you'll need a TSO'd Mode S or UAT transponder, and a TSO'd high-integrity position source like WAAS GPS. "Built to the TSO" won't be sufficient, it has to be certified.

The ADS-B Advisory Circular...

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC%2020-165.pdf

is really dense and confusing, but it's the best document available on what you'll need to do to comply with the ADS-B mandate in 2020.

Hope this helps,

Dave (former DOT ADS-B engineer)

Mike D
06-13-2010, 05:24 PM
What about just using ADS-B in? Anything FAA or FCC to worry about here? Or is it going to be a concern that if you donít have ADS-B out they will block the ADS-B in?
I love what ADS-B promises so I can get away from XM and also see the traffic.

todehnal
06-13-2010, 05:52 PM
Okay! I'm ready to place the order for my avionics package for my, in progress, RV-12. Basically, it includes a Dynon D180, an SL40, a 496 GPS, and a GTX 327 transponder. So, do I opt for a mode S, GTX 330?? If that will satisfy the ADS/B out, and I do it now, I can make that swap for about $1000. Or, would that be a premature move?? I know that Van's offers this mode "S" option to accommodate the European market

Tom

Thermos
06-14-2010, 06:07 AM
What about just using ADS-B in? Anything FAA or FCC to worry about here? Or is it going to be a concern that if you donít have ADS-B out they will block the ADS-B in?
I love what ADS-B promises so I can get away from XM and also see the traffic.
I'm more familiar with the Mode S link than UAT, but if the NavWorx UAT unit works without transmitting - and it essentially does, as far as I can tell - then it looks like you're getting ADS-B In information. Once you start transmitting your position, though, all those requirements will apply in full force.

I wouldn't be surprised if the FAA issues some policy about using a non-TSO'd ADS-B unit for traffic avoidance, kinda like using a handheld GPS receiver for IFR navigation....

Thermos
06-14-2010, 07:48 AM
So, do I opt for a mode S, GTX 330?? If that will satisfy the ADS/B out, and I do it now, I can make that swap for about $1000. Or, would that be a premature move??
If it were me, I'd buy the least expensive equipment necessary to get through the next several years in the current ATC system - and give the avionics manufacturers some time to catch up to the ADS-B Out mandate with a wider variety of products. By 2020, I'd hope that they'll have better/cheaper solutions than they have now.

Also remember you're going to need a certified WAAS GPS; the GPS-496 that Van's sells as part of the standard package almost certainly won't be approved as an ADS-B position source.

Dave

Brantel
06-14-2010, 08:10 AM
Good advice!!

But I bet the requirements for a "Position Source" will be much different than that of the precision/regs required for shooting approaches down to minimums.

I suspect that we will see a less costly alternative for the "Position Source" compared to a TSO'd WAAS enabled panel mount.....What that is who knows but if there is to be anything left of small time general aviation, someone better get a grip on what this is going to cost those of us that can barely afford to participate in this great hobby or there will be alot less of us around and bunch more RV's for sale for pennies on the dollar...

If it were me, I'd buy the least expensive equipment necessary to get through the next several years in the current ATC system - and give the avionics manufacturers some time to catch up to the ADS-B Out mandate with a wider variety of products. By 2020, I'd hope that they'll have better/cheaper solutions than they have now.

Also remember you're going to need a certified WAAS GPS; the GPS-496 that Van's sells as part of the standard package almost certainly won't be approved as an ADS-B position source.

Dave

rracer10
06-14-2010, 09:52 AM
Stein,
What is your take on minimum equipment requirements for ADS-B IN and ADS-B OUT. Have you already installed Avionics that meet these requirements ? Can you shed some light on the subject? :confused:

Thermos
06-14-2010, 10:25 AM
But I bet the requirements for a "Position Source" will be much different than that of the precision/regs required for shooting approaches down to minimums.
Brian,

You're right, I don't think the accuracy limits for ADS-B are as tight as for LPV or other GPS approaches.

What WAAS buys you, in addition to better accuracy, is better integrity - it helps ensure that your accuracy stays within specified limits, and warns your WAAS GPS receiver when when accuracy goes outside those limits. That's one big reason that it's an approved position source for ADS-B.

Dave

kentb
06-14-2010, 10:44 AM
For ADS-B transceiver. Their unit includes it's own GPS/WASS receiver.
I am working at wiring the plane now. Bill (at NavWorx) is guessing that they will start shipping with in a week or two. They just received FAA approval and are now waiting on the FCC to bless the output of the unit.

Kent

Dave Cole
06-14-2010, 10:51 AM
Actually it's RAIM, or Receiver Autonomous Integrity Monitoring that assesses the integrity of the GPS signals. RAIM is available on GPS receivers that do not have WAAS, like the GNC 300XL for example. All TSO'd GPS receivers approved for IFR flight are required to have RAIM.

Brian,

You're right, I don't think the accuracy limits for ADS-B are as tight as for LPV or other GPS approaches.

What WAAS buys you, in addition to better accuracy, is better integrity - it helps ensure that your accuracy stays within specified limits, and warns your WAAS GPS receiver when when accuracy goes outside those limits. That's one big reason that it's an approved position source for ADS-B.

Dave

Thermos
06-14-2010, 11:49 AM
Dave,

Both RAIM and WAAS perform integrity monitoring. As you pointed out, RAIM does that function on-board the aircraft by receiving GPS additional satellites. WAAS depends on ground station monitoring of GPS to detect an out-of-bounds condition. WAAS also provides differential corrections to improve GPS receiver accuracy.

ds

N130WN
06-14-2010, 08:09 PM
For ADS-B transceiver. Their unit includes it's own GPS/WASS receiver.
I am working at wiring the plane now. Bill (at NavWorx) is guessing that they will start shipping with in a week or two. They just received FAA approval and are now waiting on the FCC to bless the output of the unit.

Kent

Cool. What are you going to use to display the ads-b info? Pls keep us informed of your progress!!

Noah
06-14-2010, 09:07 PM
I was all ready to install the Navworx ADS-B receiver until I really dug into the pros and cons of getting traffic and weather via ADS-B instead of other currently available means.

Most importantly, the FAA is now operating ADS-B in such a way that you will not receive nearby traffic unless you are transmitting ADS-B out (need a transceiver, $1000 more) or there happens to be another ADS-B transmitting aircraft VERY close to you. The FAA is not transmitting all traffic in the volume, only the traffic near ADS-B out equipped aircraft. This is a HUGE disadvantage and basically means that the only reason to get a receiver ONLY is to get weather ONLY.

Several other factors have led me away from being an early adopter. First, weather is not yet available on AFS, which is what is going in my panel. Might be remedied soon, who knows. Second, I don't believe that you will ever receive an ADS-B signal on the ground in most places. Hence no weather and no traffic until you are airborne, often until you are at several thousand feet. This means no preflight weather planning - a big disadvantage compared to satellite weather. And generally no warning about traffic in the pattern unless they are ADS-B OUT (transmit) equipped. Third, the ADS-B weather product is less feature-rich than the satellite weather products currently available. And finally, there is no aural warning when there is a traffic conflict. So if you aren't looking at the display, you aren't going to know that there is a traffic conflict. The Garmin GTX-330 provides aural warnings of traffic in the headset along with "tracks" on the screen which identify the direction traffic is going - which allows one to quickly determine whether traffic is a conflict via just a quick glance.

I was pretty psyched about installing this until really digging into it. It just doesn't make sense to me now that I know the trade-offs!

NavWorx
06-15-2010, 09:14 AM
When will MGL support ADS-B?

Radomir
06-15-2010, 09:30 AM
What was this FAA approval that NavWorx obtained?

When will they have a TSO'd unit that can be installed in a certified plane?

Is there a requirement to have an "approved" WAAS GPS? I thought Navworx had a built in GPS (of unspecified origin) and it's unclear if that's legal to use?

az_gila
06-15-2010, 10:08 AM
What was this FAA approval that Navajoes obtained?

When will they have a TSO'd unit that can be installed in a certified plane?

Is there a requirement to have an "approved" WAAS GPS? I thought Navworx had a built in GPS (of unspecified origin) and it's unclear if that's legal to use?

...is an ADS-B IN receiver, and would not need the TSO approvals since it does not transmit position/altitude/speed etc. data OUT.

The FAA apparently want to ensure that all aircraft position data is "certified".

Now if you use it with a late version GTX-330 transponder fed from a WAAS GPS, then you get the ADS-B OUT bit...

...or did I screw this up...:)

Radomir
06-15-2010, 10:25 AM
I'm specifically referring to their In/Out UAT (the one we've been discussing so far in this thread ;) )

NavWorx
06-15-2010, 10:28 AM
I'm more familiar with the Mode S link than UAT, but if the NavWorx UAT unit works without transmitting - and it essentially does, as far as I can tell - then it looks like you're getting ADS-B In information. Once you start transmitting your position, though, all those requirements will apply in full force.

I wouldn't be surprised if the FAA issues some policy about using a non-TSO'd ADS-B unit for traffic avoidance, kinda like using a handheld GPS receiver for IFR navigation....

We sell both UAT receivers (ADS600), and UAT transceivers (ADS600-B). For the ADS600-B, we expect to receive our FCC certification this week and begin delivery of orders already taken.

The change from DO282A to DO282B was the FAA's mechanism to address non-TSOed UAT devices.

Bill Moffitt
NavWorx Inc.

kentb
06-15-2010, 10:29 AM
I will be using AFS 3500 for display. The unit connects to ser # 2 and receives alt. info from it and sends TIS packets through the ser to it.
Currently the AFS software only supports traffic on the screen, but AFS said that they are working on the weather.
I also have a 496 on the panel for weather, so that is not a big issue for me.
As for weather on the ground, I would use my iPad to check for most current weather before I departed the airport. The NavWorx unit can be set for sensitivity in 0.1 mile intervals, so you can control how much traffic information is sent to the AFS. I don't know how many target the AFS unit displays. As for audio warnings, I would like to see that as a feature added to the AFS. You would need to be able to set the warning settings.

I am mounting the unit behind the baggage compartment and running wire to the front. I am also mounting the GPS antenna in the front under the cowl, so am running the coax for that at the same time.
There is the transceiver antenna the I will be mounting under the fuse aft of the baggage compartment.

I'll update with pictures and comments when I get my unit.

Kent

NavWorx
06-15-2010, 11:07 AM
To sell a transmitting device in the US, one needs to obtain FCC approval. For aviation frequencies, the FCC defers certain decisions to the FAA.

Our ADS600-B transceiver (ADS-B OUT & IN) received the FAA's letter of determination about 10 days ago. This letter goes to the FCC for their review along with the FCC test report, etc. The FCC then issues our FCC ID which will allow us to sell the ADS600-B.

So you can see that the FAA is aware of the product's existence. And they should be since they selected our ADS600-B (purchased through a third party) to be used on their ADS-B flight-check aircraft.

We continue working towards the TSO....



Bill Moffitt
NavWorx Inc.

fmarino1976
06-15-2010, 05:34 PM
Today one of the ADS-B manufacturers for certified aircraft visited my place of employment and we had a 2 hr presentation on the whole ADS-B system. I'll try to relay some of the information here.
The ADS-B in the US will have 2 frequencies. The 978 MHz band will be aimed at general aviation and will operate under 18K ft. To meet the ADS-B mandate, an aircraft flying under 18K ft will have to have only a mode A/C transponder and a 978MHz transmitter. The transmitter will have to receive WAAS GPS information.
Currently, the FAA is reducing the transmit power of the ADS-B stations if there are no ADS-B out equipped aircraft in the vicinity, thus the ADS-B in only aircraft might not have info all the time.
An aircraft flying above 18K ft, in order to be ADS-B compliant will need an approved mode S with extended squitter transponder (1090 MHz frequency). The rep told us that due to a change in the TSO, at the moment there are NO ADS-B compliant mode S transponders out there, NONE.
The way I see it, for an experimental aircraft, the best solution might be to install a basic transponder and wait for a ADS-B in/out transceiver to come along. This way you will be able to receive all the TIS and FIS info provided on the 978 MHz band.
Another interesting bit of info was that the FAA projects that by the end of this year, ADS-B will cover 70% of the US, and by 2013, the coverage will be equal or better than current ATC radar coverage.
I'm sure I'm forgetting something, but I'll try to answer if you guys have any questions.

digidocs
07-08-2010, 11:06 PM
Bill,

Would you mind explaining the FAA's position about whether TSOs are required for UAT transmitters like your new model?

My reading of the ADS-B final ruling lead me to believe that the UAT equipment would have to be TSO'd. However, you seem to be selling a non-TSO'd, legal, UAT transmitter. What are the actual requirements?

-DC

FreeFlightSystems
07-21-2010, 02:38 PM
Let me see if I can help clarify the UAT certification issue

FCC approval means that the radio transmits at the right frequency, at the right power, and doesn’t spew energy into other parts of the spectrum.

FAA endorsement of the FCC approval means that the FAA agrees it transmits at the right frequency and at the right power.

This of course has absolutely nothing to do with operational approval of an ADS-B system. ADS-B is a part of the larger change in the airspace system towards satellite based navigation - in fact, it is the principal Air Traffic Management tool for the next few decades. As such we should be thoughtful about how we interact with it - for our own safety and for the safety of those around us.

An approved airborne ADS-B transmitter has two components - a high integrity position source and a radio that sends information from that position source (along with other elements) to the Air Traffic Control (ATC) system. The ATC system uses that information, integrated with other data sources (radar when its available for instance), to determine safe separation, provide flight following and other ATC services, and furnish highly accurate fixes to Search and Rescue teams should that be necessary. The position source requirements are essentially the same for all aircraft types. This makes sense since we all share the same airspace.

If an aircraft ADS-B system is not meeting the integrity and accuracy requirements that have been defined for valid operation, it will tell the ground system (since there are integrity and validity flags in the message) and the ground system will reject the aircraft as an air traffic target - in fact any info on the aircraft is filtered out and never even gets to the ATC system.

In an environment where the ATC system is relying on this self reporting, being rejected is not good for you or for anybody flying in your immediate vicinity. In areas where there is radar coverage, they will pick you up anyway - no harm no foul. However, ADS-B will cover more of the airspace system than the current radar system - and the radar system is gradually going away. In this case you are invisible if your ADS-B system is not meeting standards. This is why the FAA is requiring that almost everybody (basically if you need a transponder today you need ADS-B tomorrow) equips with a compliant system.

In return for equipage, the FAA is providing free services back to the aircraft via ADS-B “in” - basically traffic and flight information services such as graphical weather. The ADS-B ground system today is sending the Flight Information (including weather) to anybody with a compatible receiver, and they are sending traffic to anybody who sends an ADS-B signal - valid or not. This will change shortly and they will be filtering the
traffic message and power modulating the Flight Info message.

For experimental category aircraft the certification process for ADS-B systems will most likely follow the model of other “for credit” equipment having a safety impact on surrounding aircraft. The easiest way to get sign off will be to use TSO equipment. Equipment that meets the minimum standards does not have to carry a TSO but you will have to show that the minimum performance is met - and a manufacturer saying that his unit is good enough is not going to cut it - unless he has a TSO unit and can demonstrate that the non TSO product is identical.

So - in summary. An ADS-B radio that meets FCC standards but not operational standards, and which has an unapproved position source, can be used to trigger a traffic broadcast from the FAA until such time as they close that loophole. The traffic picture you get will assume that your GPS position is actually correct, so good luck with that.

For further questions regarding ADS-B, check out ADS-B FAQs (http://blog.freeflightsystems.com/ads-b-frequently-asked-questions-part-1/)

I would think seriously before committing this amount of money to something that has apparently limited utility.

az_gila
07-21-2010, 04:26 PM
..... Equipment that meets the minimum standards does not have to carry a TSO but you will have to show that the minimum performance is met - and a manufacturer saying that his unit is good enough is not going to cut it - unless he has a TSO unit and can demonstrate that the non TSO product is identical.
.....

...that the non-TSO unit would be the same price as the TSO unit?

If you change/delete the QA requirements, can you say the units are identical? ...or can you just reduce the test requirements?

Thank you for the detailed explanations you posted...

Ron Lee
07-21-2010, 04:58 PM
Reference post #30, my opinion is that ADS-B is not a navigation system,...rather surveillance.

The onerous mandate for ADS-B Out does not include ADS-B In "free" stuff so unless you find a way to get the Insies stuff, it is a net cost negative for GA pilots.

NavWorx
07-21-2010, 10:09 PM
.... Snip all of Freeflights post.....

What can I say about a post like this - except that it's full of half-truths and inaccuracies. Though this is what I expected from any company who doesn't have the technical expertise to take on the design of their own UAT equipment. They first partnered with us, then decided when it became available, to use a quasi-government entity's "free" system. The only problem with that is that they still have no expertise, as illustrated in their post.

Of course FreeFlight wants you to "think seriously before committing this amount of money to something that has apparently limited utility". I'd agree if it were only true. The system that we sell offers full utility for what the FAA is offering today. And, If they think that "this amount of money" (which our system is $2495) is a lot, they should take a look at their own prices (<10K just for one of their certified GPS receivers).

I like the way FreeFlight dismisses the effort the FAA performed when they approved us to sell our UAT transceiver: "FAA endorsement of the FCC approval means that the FAA agrees it transmits at the right frequency and at the right power." If that truly was the case, the FCC could have merely passed a memo to the FAA stating such. Reality check for Freeflight - the FAA could have adopted the position that no non-TSO'd ADS-B out devices would be approved. But the FAA <wants> UAT OUT devices in the marketplace - now! This is one reason why they updated DO-282A to "B" status. There are now extra bits in the transmit messages that show the design approval level of the device. By the way FreeFlight - you too can apply for an FCC license and sell your ADS-B OUT device - you do have one, right?

In regards to their comments regarding coverage, if someone is transmitting ADS-B OUT using our equipment, it will be received directly by other ADS-B UAT systems - period. All displays in the market today will then display the target generated by our equipment. And it will display them accurately in the horizontal direction, since we utilize an internal WAAS GPS. Or our customers can input certified WAAS GPS via an ARINC-743 Position Source interface. In the vertical direction, altitude is as accurate as a certified altitude encoder that should already be installed in the aircraft. So contrary to what FreeFlight says above ("The traffic picture you get will assume that your GPS position is actually correct, so good luck with that.") Every pilot knows that the transponder sends altitude information from a certified altitude encoder. The same applies to ADS-B. Our products accept either an Icarus serial encoder input or ARINC-429 altitude label 203. Our transmitter transmits this altitude so that the FAA and other receiving aircraft will be able to accurately determine the altitude difference for purposes of determining an on-screen target. Our receiver uses this same altitude source to compute the altitude difference against an incoming target.

ATC may not use a non-TSO'd ADS-B signal for <surveillance> (and that date isn't until 2010 BTW), but they are relaying it to the alternate data-link, 1090ES equipped aircraft willl be aircraft equipped with our UAT. Result? Entire coverage of traffic using our UAT transceiver. I'd say that's FULL UTILITY.

I've encountered other articles lately that talk about the certified position source, and here's some information that most don't know - FreeFlight no doubt included - the FAA is working on another TSO that would incorporate an "off-the-shelf" non-certified GPS. The FAA realizes that not all aircraft out there today will be able to afford a $6K+ certified WAAS GPS. I wonder why FreeFlight didn't mention that? Was it because they sell certified WAAS GPS modules and this news might affect their sales? When/if this comes to fruition, we'll be able to take the NMEA GPS position from, say, the Garmin 696.

Just an FYI, if you do need a certified GPS source in your airplane, and you don't have one now, we are reselling the NexNav mini GPS WAAS Class Beta-1 product. We also intend on offering a TSO'd UAT transceiver that integrates the NexNav certified WAAS GPS. All at a total cost far, far below what FreeFlight is offering today.

So let's sum up who is in the market today. NavWorx with a UAT product that meets DO-282B A1S specifications (40 watts single antenna), designed and engineered by pilots, for pilots. Supporting the pilot-owner by reselling NexNav certified WAAS GPS for less than $5K. Backed up by technical support by pilots, A&Ps, and engineers.

FreeFlight with a ground beacon that meets the old DO282A specification (8 watts single antenna - can't use it in an airplane), as well as a certified GPS WAAS unit that is way overpriced (their 1203 product lists for $9,133.00). Good luck with that.


Bill Moffitt
President
NavWorx Inc.

NavWorx
07-21-2010, 10:17 PM
Bill,

Would you mind explaining the FAA's position about whether TSOs are required for UAT transmitters like your new model?

-DC

David,

In 2010, the date when ADS-B becomes mandated, The FAA will no doubt have in place an FAR specifying that all ADS-B OUT devices must be TSO'd - similar to the FAR that states the same for transponders.

I'm sure ours will be certified by then :)

So don't let anyone discourage you from installing non-TSO'd devices today - the FAA has approved our non-TSOd product because they need ADS-B participants.

Bill Moffitt
NavWorx Inc.

tacaruth
07-22-2010, 07:32 AM
Will traffic display of ADS-B IN equipment display only other ADS-B OUT aircraft or will it add in other aircraft from radar sites? If it does not display non-equipped aircraft, what's the point? Having a mid-air collision with a non-equipped aircraft would be as bad as an equipped aircraft. Until we get closer to the "required" date, is there a real "traffic" advantage to ADS-B IN?

Tom
RV-7A N175TJ Flying

Ron Lee
07-22-2010, 09:47 AM
Excellent question Tom. I will offer an OPINION and Bill can correct me if I am wrong. My understanding is that ADS ground transmitters will broadcast Traffic Information Services (TIS). That "may" include aircraft using the other frequency band, maybe even Mode-C traffic. I have not read this for a while so can't say for sure.

But you raise a good point. One intent of the flawed ADS-B concept is to reduce FAA radars...hence costs. If radars go away, Mode-C returns are reduced. So you could have aircraft with Mode-C only who would apparently not show up on your ADS-B In system.

If I read Bill's post correctly, TSOd GPS/WAAS data is needed to transmit via ADS-B Out. I don't understand the non-TSO exception for circa 2010. If it has to be TSOd, how much will that increase the cost to equip for ADS-B Out only for people without TSOd GPS units? Will a TSOd GPS/WAAS be in many/most ADS-B Out units?

FreeFlightSystems
07-22-2010, 10:27 AM
...that the non-TSO unit would be the same price as the TSO unit?

If you change/delete the QA requirements, can you say the units are identical? ...or can you just reduce the test requirements?

Thank you for the detailed explanations you posted...

As a manufacturer - once we have a TSO unit we have the option to sell the same unit at a lower price for applications that do not require certified equipment. As to claiming it meets the performance of the TSO box - we can say that it is the same design, built to the same standards. As always, the approving authority (different for different classes of aircraft) can accept or not accept the unit. From the manufacturers point of view the difference is that we are certifying that a TSO label unit meets standards and just saying it for the non TSO unit.

At the end of the day it is usually easier to just go with the TSO unit for anything that is going to require any kind of FAA approval - but for experimental aircraft we think that a non TSO but conforming unit should be acceptable. The ADS-B rule and associated Advisory Circular for certified aircraft was finalized and published in May of this year - so there is no confusion about standards for that community. As always there is less clear guidance for the experimental community.

FreeFlightSystems
07-22-2010, 10:35 AM
.... post entirety.....


Apologies to members of this thread for triggering an inter-company discussion. This is not our intent. We are happy to help develop understanding of ADS-B and promote the adoption of the technology - if properly applied it enhances safety, provides valuable services and increases the capacity of the airspace system. We are part of the industry / government team that is developing standards for ADS-B "in" and we are working to make that service as accessible and affordable for the general aviation community as possible. We are also part of the working group that is finalizing the detailed definition of the interaction between the ADS-B ground system and the client aircraft. We know ADS-B, we know avionics.

We have ADS-B resources on our website (http://freeflightsystems.com/) and blog (http://blog.freeflightsystems.com/) and we will be at Oshkosh.

Please feel free to contact us directly or through these forums if we can be of any assistance.

FreeFlightSystems
07-22-2010, 11:18 AM
Will traffic display of ADS-B IN equipment display only other ADS-B OUT aircraft or will it add in other aircraft from radar sites? If it does not display non-equipped aircraft, what's the point? Having a mid-air collision with a non-equipped aircraft would be as bad as an equipped aircraft. Until we get closer to the "required" date, is there a real "traffic" advantage to ADS-B IN?

Tom
RV-7A N175TJ Flying

Here is how it works. The ground station listens for ADS-B messages from nearby aircraft and logs their position and velocity and several other bits of data - including a request from the aircraft for the ground system to transmit traffic on one of two frequencies - 1090 or 978 MHz (this "bit" is set as part of the transmitter installation). The ground system then sends out a traffic message that contains radar traffic, and ADS-B traffic transmitting on the frequency you did not select. The idea is that you can see aircraft on your selected frequency directly and the ground system will not rebroadcast it to save RF clutter and to simplify the job of the receiver. You therefore get to see everybody that is following the rules (ADS-B or radar / transponder). You can request the traffic uplink on a different frequency than the one you are transmitting on, so you can for example have a compliant ADS-B system that is using an approved 1090 MHz transponder as the transmit radio and you can request traffic at 978 MHz - if that is the type of receiver you have installed. The final detail is that the ground system transmits a "hockey puck" of traffic data centered around each aircraft client. From the aircraft, it looks like they sent a message to you (as long as your GPS position is right) but it is actually a broadcast. If there is more than one client in the area, the ground system sends the combined hockey pucks - but to each aircraft it looks like a unique message sent to them. This is one reason why you need to make sure that the ground system is recognizing you - it could send a hockey puck for an aircraft that is near to you that is missing some traffic that is very important to you. As I said in the earlier post, the system today sends a hockey puck for any aircraft that is transmitting an ADS-B signal - valid or not. This will likely change here very soon as the FAA upgrades the ground system software to the new standard that takes full advantage of the latest (final) aircraft requirements that were published in May as part of the final rule and installation advisory circular. There are links to those docs on our website (http://freeflightsystems.com/) if you have time to wade through them.


Sorry for the lengthy reply but this is a complex subject.

FreeFlightSystems
07-22-2010, 03:54 PM
... I don't understand the non-TSO exception for circa 2010. If it has to be TSOd, how much will that increase the cost to equip for ADS-B Out only for people without TSOd GPS units? Will a TSOd GPS/WAAS be in many/most ADS-B Out units?

Ron - not trying to hijack your conversation but here are some thoughts about the radar vs ADS-B question. Only the FAA actually knows how they will do this. However, after talking to them about this many times, I think the following is about right:


Bill meant 2020.


I think you are right about the radar vs ADS-B issue - long term the FAA will reduce radar and increase ADS-B, so there will increasingly be areas that have ADS-B coverage and not radar coverage. I believe the answer is in the timing. The FAA will have their first roll out complete by the end of 2013 - at which point they will have all the existing radar airspace covered by ADS-B. I think they will have some 70% of that done this year but I am not confident I have that right.


I think that between now and then the FAA will keep most of the radars up and running. If they do lose radar coverage in an area (maintenance, budget or on purpose) my guess is that they will somehow require ADS-B for that particular airspace before the January 1st 2020 mandate - primarily so they can maintain ATC services, but this addresses the traffic picture question you raised also.


On the GPS question - like everything else the FAA will never require that you use TSO equipment - but they make it very difficult to get operational approvals without - at least for certified aircraft. I expect that most manufacturers will be integrating TSO GPS into their ADS-B devices. This will drive costs some but the sheer quantity of aircraft that need to be updated will provide enough volume to keep it reasonable - I don't see it getting down the $19.00 WAAS receiver that the automotive guys use....

SteinAir
07-22-2010, 05:37 PM
Here's the deal guys...this is an incredibly complex issue at the moment that is somewhat difficult to sort through since our friendly FAA hasn't exactly seen fit to clarify it to the point where everything including the timing written in stone (as it sits this instant) - and that all changes with the politicians.

Anyway, the way I look at it is that we are lucky to have two very competent companies participating in this thread. One may not agree with the other 100% of the time on 100% of the stuff, but I know both companies and neither one is a bunch of idiots. Navworx is making a huge splash with some excellent equipment that is nicely priced and they are really great guys to work with (really smart too). That being said, there is no reason to be negative about Freeflight either - even if you disagree with then, there are polite ways of making your point without being negative. They have been around many, many years and have been doing WAAS GPS and other various bits of technology longer most other mfgr's have. One mustn't forget that they were one of the very few companies that stood by their customers and made things right by them during the Chelton/D2A debacle some years ago..that speaks to integrity and business practices as much as anything.

My point is that I have worked with both companies and I'm glad both are participating in this disucssion, even if there is some disagreement on various items. I know I add nothing of any substance, but I just wanted to point out that both companies have information that is of value, at least in my opinion. I'd like to see it stay civil if we can....

My 2 cents as usual!

Cheers,
Stein

hpmicrowave
07-22-2010, 06:28 PM
I have been working with MGL-Rainier and can say the NAVWORX Arinc Traffic displays as designed on the MGL Odyssey and Voyager (with lattest MGL SW updates). I live along the Gulf Coast and the ADSB system here has limited ADSB Traffic uplinks over some of the Gulf Oil Platforms, even though Houston Center can recieve and monitor any ADSB-Out equpped aircraft, but only in their technical center. Weather is being transmitted over the whole Gulf Coast system but can only work over RS-232 out of the NAVWORX reciever as their is no Published ARINC weather message standards. Rainiers next goal is to get NAVWORX weather integrated on their EFIS. I can recieve ADSB weather from my house so have been recording and shipping Rainier test message traffic to support integration and Bill at NAVWORX has been very helpful in answering questions. So all its coming, its just never easy!!

C jones

Brantel
07-22-2010, 07:55 PM
It is exciting to see the birth of a brand new system for ATC....

Some day in the future we will be telling the young pups about back when we use to use a thing called RADAR and we had to call a guy on a land line telephone to get a weather briefing. Oh and we had to look out the window to avoid other airplanes.

I just hope all of these smart guys figure out how to make all of this affordable for the masses of GA. For this to take off, everyone with a mode C transponder today needs to be able to get ADS-B out and IN to include the advance traffic and weather in the cockpit for a reasonable cost.

My guess is that if that can't be done when the mandate hits for less than $3000, GA (at least the part that I participate in) is doomed!

Keep the cost down by making the data viewable on the EFIS's and portable GPS's we all have today in our cockpits. This will require effort on the part of the manufacturers of those devices to make em compatible.

There is absolutely no reason why the position source for ADS-B out needs to cost $8000! You can get a WAAS GPS puck for $99 that is accurate to within 20ft 99.8% of the time so why would we need such a high dollar position source?

Looks like Navworx is on the same page as the way my mind and wallet thinks. I just hope the Feds don't make it impossible for them to stay on that page!!!

My per hour operating fund now needs to include a few bucks for the ADS-B mandate....

Rainier Lamers
07-23-2010, 12:20 AM
It does not matter what anybody thinks about ADS-B at this stage.

ADS-B IS THE FUTURE and it will simply wipe out any alternative there may or may not be. Expect ADS-B receivers (which is what most will want) to be plentyful and very low cost (I mean REALLY low cost). There is no subsciption cost either.

The system is good (in fact it is excellent).

Just hang in there - wait for it to be rolled out. It is ahead of schedule and even that should speak a loud message.

Rainier
CEO MGL Avionics

Rodoc
10-21-2010, 10:41 AM
David,

In 2010, the date when ADS-B becomes mandated, The FAA will no doubt have in place an FAR specifying that all ADS-B OUT devices must be TSO'd - similar to the FAR that states the same for transponders.

I'm sure ours will be certified by then :)

So don't let anyone discourage you from installing non-TSO'd devices today - the FAA has approved our non-TSOd product because they need ADS-B participants.

Bill Moffitt
NavWorx Inc.

Hey Bill,
Thanks for working so hard to supply us all with a lower-cost ADS-B solution. I am about ready to jump in, as I have been wanting a good traffic solution and have been waiting for a low-cost UAT (like yours) and for TIS-B/FIS support to come to California.
Two fears still remain for me. First is that the FAA will come out with a new TSO for ADS-B out (if I want to use it after 2020) or that they will change the policy and only supply TIS-B data to aircraft that have a certified UAT and/or GPS (like the guy from Freeflight suggests they will do soon). In either case, I would be stuck with a useless (or nearly useless) UAT. You guys could really help us potential early adopters buck up by offering guaranteed free or minimal cost upgrades to continue to meet FAA requirements.

For example, if I bought your current unit for $2500 and the FAA changes the requirement and you come out with a compatible unit that costs $2900 but I knew that I could get the upgrade for only the $400 difference in purchase price (plus maybe minimal shipping and possessing), I would feel a lot more confident jumping in. Of course, by then prices may have some down and the newer certified units might be costing less than $2500. In that case I would be looking for a free upgrade.

That being said, I would understand if the FAA started requiring a certified GPS. Then it would be up to me to upgrade my GPS one way or another (and I am re-assured that you are planning a lower-cost certified GPS to be used with ADS-B).

You may end up loosing a little money on making the upgrades, but I would think that would be more than offset by the markedly increased sales at this point while you are trying to get production up and running full speed. You would also be locking in a marked share.

Think you could offer such a guarantee?

Ron Lee
10-21-2010, 06:36 PM
It does not matter what anybody thinks about ADS-B at this stage.

The mandate may be there but 2020 is a long ways off. Don't count on this system being required for GA.

TCONROY
10-22-2010, 09:47 AM
Here in Oregon the ADS-B system already requires you to transmit your position (ADS-B out) before you can receive traffic on the uplink. I'm not opposed to it....you've got to help out others by transmitting your position if you want to receive other targets.

Cement85
11-28-2010, 01:27 PM
Is the ads-b weather available now in the mid west?

Ron Lee
02-01-2011, 05:19 PM
http://www.gpsworld.com/gnss-system/news/data-shows-disastrous-gps-jamming-fcc-approved-broadcaster-11029?utm_source=GPS&utm_medium=email&utm_campaign=Navigate_01_31_2011&utm_content=data-shows-disastrous-gps-jamming-fcc-approved-broadcaster-11029

breister
02-02-2011, 06:57 PM
Lovely. We're from the Government - we're here to "help."

:mad:

flybill7
02-03-2011, 11:48 AM
I've been hearing about the "new" ATC system they are going to build my entire adult life.

kentb
02-03-2011, 04:48 PM
The NavWorx ADS-B unit will continue to give you traffic information even with the GPS not working correctly. The accuracy of the traffic report will be effected. The up linked data will be based on what ever ATC is getting from the other targets. IE radar return or mode S, etc. Keep in mind that those other targets may not have loss of GPS signal.

I hope the FCC will get this fixed soon, because it could have very bad effects on someone flying IFR and doing a GPS approach.

Kent

rodeomanny
02-03-2011, 09:59 PM
From what little I understand of this, isn't the iFly700 also working on this in a future update; or am I completely confused here? A lot of this is totally greek to me other than the fact that it will be great to have free traffic and wx.

Flybuddy2
02-05-2011, 10:24 AM
From what little I understand of this, isn't the iFly700 also working on this in a future update; or am I completely confused here? A lot of this is totally greek to me other than the fact that it will be great to have free traffic and wx.

Yes they are, but the IFLY will really only act as a display for an ADSB receiver. As the display is a bit weak in sunlight it probably isn't the optimal answer. Good thing about IFLY is that the owners are very flexible with their product and are working on weather, traffic and a 2nd gen display. It doesn't hurt that they also believe in reasonable pricing.

rodeomanny
02-05-2011, 11:37 AM
Yes they are, but the iFLY will really only act as a display for an ADSB receiver. As the display is a bit weak in sunlight it probably isn't the optimal answer. Good thing about iFLY is that the owners are very flexible with their product and are working on weather, traffic and a 2nd gen display. It doesn't hurt that they also believe in reasonable pricing.

Amen to that! Flexibility, good customer service and reasonable pricing like Adventure Pilot has shown will go a huge way in their ultimate success. I for one am pulling for them and will bend over backwards to give them my business.