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Possible AD for certain NAVWORX ADS-B Units

GalinHdz

Well Known Member
Shamelessly plagiarized from another forum: "It looks like there is an AD coming on the Navworx ADS600-B -012, -013 and the EXP 8013 ADS-B Transcievers. The proposed AD is located here. If you are impacted, you have 60 days to comment."

:cool:
 
Hmmmm.

Hmmmm. This isn't great news. Perhaps the Navworx folks can provide some back story? I'm really hoping to buy two of the -EXP units next year.
 
I'm impacted

The Navworx 600EXP has been installed in my plane about three months. I'm already spoiled and don't want to think about flying without this traffic and weather. Is this just a software issue, something they can rewrite? It looks like this AD will effect about 800 of their ADSB units. Hoping Navworx will chime in today!
Edited: I went to Navworx site and there is information there regarding UPN or unapproved parts notification... what ever that means... and at the end it states to write to the FAA administrator or your congressman.

I'm upset!
 
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It sounds like the FAA's beef is about the GPS accuracy (which they issued a certification to). For those who have a certified WAAS position source, I would presume that this would "fix" the issue, but I haven't heard this mentioned anywhere.
 
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NavWorx Proposed AD

You have to wonder if the Big Guns producing Expensive ADSB products are working behind the scene to Torpedo NavWorx.
 
I hope it gets solved too. I've got a 600 Exp still sitting in th? box waiting to be installed in January. :mad: I don't Know exactly which mod?l, I just Know it 's a 600 Exp.
 
I've contacted NavWorx - no answer on what they plan to do for their customers - I asked a bunch of pointed questions.

They did request that I comment on the AD - which I did.

Recommend all y'all do the same!
 
I have the model of the 600-B which is affected, but haven't flown yet.

Unfortunately, I don't know about the particulars to provide comment! Do I take Bill's side and argue/comment against the FAA findings?? Is that in my best interest? I know removing or in-opping the box isn't the long term solution, but where do we go? - I need to know the consequences....

I've read the proposed rule and Bill's response, and it sounds like a he said/she said that is actually brought about by the software upgrade. I'm hopeful that a new software update will fix the problem.

Phil Barnette
RV-10 Finishing... still... and forever....
Salt Lake
 
From what I understand, the software upgrade was at the FAA's request to make the device's accurate. The fAA originally certified the functionality with the non-certified internal GPS - then told NavWorx that they had to put out the 'other' SIL to be accurate - then they can say 'bad SIL, no data'. The FAA put NavWorx in this spot by certifying the functionality initially then changing the documentation rules - to fit their scenario.

Again, my understanding from reading both the AD in the FAA website and NAVWORX response on their website.
 
my not so humble view

Lawyers got involved. That backs the FAA into a corner. And remember, we pay for their lawyers too. Most of us here on VAF will not have to worry. If we operate the 600-exp box. Now, I did write in to the FAA this morning to ask if I was at risk of a mid-air collision, using my Navworx experimental. I am baiting them of course. Since we fly in the same airspace as certified, but they have no problem with my GPS source. I want to see in writing, their explanation of how one is safe and one is dangerous.
Their logic is sometimes quite interesting. I once crashed a fully fueled plane in the desert. It lay there upside down for three days. When the wrecking crew finally came and got it, the fuel was all in the sand. The FSDO (Riverside) said I ran out of gas. I provided my fuel receipt from thirty minutes prior to the crash, showing a top off. Their reply, and I kid you not... was "that just proves you bought fuel... not where you put it" I had to undergo a 709 oral re-examination of my ratings. They include ATP single, ATP multi, CFI-I, helo, balloon, fixed, seaplane. I was just astonished at the logic of FAA employees.
When the Fort Worth ACO gets straightened out by D.C. we shall see non TSO GPS receivers in ADS-B down the line. But for now, the lawyers are billing in the neighborhood of $700 per hour. Man, what a system.
 
So on the website, where it says (essentially, not writing exactly) that the FAA stopped sending data to their products, they mean only the product numbers listed there? Not, the EXP? Just trying to figure it out because the EXP seems to be what I'm looking for but I want to make sure.
 
The exp receiver is not affected. I fly mine daily... works fine.
This began when owners of the non TSO GPS receiver chip set... applied for a $500 rebate. We experimental types are not incentivised by any such rebate.
The focus then went on the subtle part number change from Navworx where they removed the Accord certified GPS receiver and substituted a commercial non TSO receiver. The software continued to put out a SIL 3 code... meaning "hey, I am OK here, I meet the criteria and performance of the other chip".
Now the FAA says unnapproved. Navworx says hold on to your hats.
They may swap out boxes with owners to solve this. Maybe, like the Samsung... a hundred bucks will be offered to cover the cost of the shop who pulls the box for exchange. Time will tell.
 
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The Navworx 600EXP has been installed in my plane about three months. I'm already spoiled and don't want to think about flying without this traffic and weather. Is this just a software issue, something they can rewrite? It looks like this AD will effect about 800 of their ADSB units. Hoping Navworx will chime in today!
Edited: I went to Navworx site and there is information there regarding UPN or unapproved parts notification... what ever that means... and at the end it states to write to the FAA administrator or your congressman.

I'm upset!

You should be upset. As described, this seems to be both a hardware and software issue. Its internal GPS hardware does not and can not meet the specs of the TSO C-154c. NavWorks' older operating software makes it appear to the FAA's system that their device is using a conforming GPS position source, which it is apparently not. The software was changed report the GPS position source's integrity accurately, which in turn makes it non-compliant. Uh, oh....
 
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The exp receiver is not affected. I fly mine daily... works fine.

This isn't about whether you think your unit is working ok. Also, the Avweb article seems to indicate the experimental unit IS affected by the proposed rule:

"The FAA says there are about 800 aircraft with Model ADS600-B part number (P/N) 200-0012 and 200-0013 and Model ADS600-EXP P/N 200-8013 transceivers installed and they?re saying it should only take an hour to take them out."

Erich
 
Pls refer to the AD language as well as Navworx notice just posted on their website. This does affect the ads600 exp as well as the certified versions. Not sure that 800 users writing the Faa or congressman telling them our units are accurate is going to change this. I would like to see something from Navworx with solutions should this ruling come to pass. Does anyone know what units are out there that are not affected. Can those components be used in the affected units? Can a 430w, 530w etc be used as position source? If so is a modification of the affected units necessary or just running new wires. Would be nice if Navworx was addressing some of this.
 
correction

I stand corrected. Contrary to what I was told by the manufacturer, even the experimental is sending out a SIL code that is misleading according to the proposed AD wording. I have heard that an alternate GPS chipset is available, that would make the FAA happy and return the units to TSO compliant status.
How that happens, what it costs and what it does to the competitive market for these avionics is unknown at this time. I am on standby, like many of us here.
 
Navworx Statement

I'm confused... the Navworx statement says

"The UPN only applies to certified aircraft installations. It does not apply to installations in uncertified amateur-built, light-sport, and unmanned aircraft. In other words, the FAA is apparently satisfied from the standpoint of national airspace system (NAS) safety that the products properly locate aircraft and transmit that information in a manner that is properly received by the ground stations as well as other aircraft."

That conflicts with some of the previous post

I literally just installed the EXP UNIT IN MY 7a. I love the FAA estimate of one hour of labor as the cost of the proposed AD to owners!

Bob Cowan, N743RV
 
Two different documents. The unapproved notice listed the certified units.
The AD proposal includes the experimental. A broader brush...
It is a notice of proposed rule.... to the public though... and open for comment.
Contact the FAA if you so desire.
 
Its internal GPS hardware does not and can not meet the specs of the TSO C-154c..

What are you basing that statement on? Technical knowledge of the equipment or the FAA statements that are being challenged by Navworks?

If it is technical knowledge, please share.

EDIT **** Just checked mine and it is a 200-0112 which is OK per the proposed AD. I guess that justifies the extra bucks that I was internally whining about after the prices dropped significantly.
 
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From navworx statement:

"FAA certified our products 3 years ago. At that time our testing demonstrated that the products? GPS module met 91.227(c) integrity. Nevertheless, the FAA required that we output at an integrity level lower than our testing demonstrated. " (bold mine)


So how many customers bought this unit thinking they are 2020 compliant? Was it advertised so? Was it disclosed to buyers that they are buying a non-compliant unit? (if you're not emitting SIL=3 you're not compliant).... and most importantly, YES a unit can be certified with SIL=0... it'd be completely useless for 2020 compliance, but it would be certified :) And, NO you cannot certify with SIL=0, then switch to SIL=3 via software update as "minor modification" down the road. That doesn't fly with the FAA (and it did not in this case).
 
Demonstrate vs Calculate

From navworx statement:

"FAA certified our products 3 years ago. At that time our testing demonstrated that the products’ GPS module met 91.227(c) integrity. Nevertheless, the FAA required that we output at an integrity level lower than our testing demonstrated. " (bold mine)


.....

Definition..

Source Integrity Level (SIL) indicates the probability of the reported horizontal position exceeding the containment radius defined by the NIC on a per sample or per hour basis, as defined in TSO-C166b and TSO-C154c.

IIRC from the Dynon discussion when they introduced the GPS2020 the SIL is a number that is calculated, rather than "demonstrated" and also, if my memory is still OK, Dynon said there were only a few people around that had the skills to do this calculation.

I wonder if this is actually what caused the problem.
 
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Sure would be nice if Bill at Navworx or Neil (AllThumbs) would respond here on VAF and let the RV community know what is REALLY happening.
 
What are you basing that statement on? Technical knowledge of the equipment or the FAA statements that are being challenged by Navworks?

If it is technical knowledge, please share.

EDIT **** Just checked mine and it is a 200-0112 which is OK per the proposed AD. I guess that justifies the extra bucks that I was internally whining about after the prices dropped significantly.

I'll share anyway: I based my statement on my ability to read the public notice of the proposed AD and certain legal training. I have no direct knowledge of the technical work performed by the manufacturer to show its "equipment maintains an equivalent level of safety" as described in TSO-C154c and related standards documents described within the order. Nor do I know why the FAA now considers the original deviation work performed by the manufacturer to be invalid in light of a software revision, other than what is mentioned in the NPRM. However, based on earlier discussions on this board, and guidance from Garmin, the ability to produce and demonstrate equipment that meets the MPS of TSO-C154c is a complex undertaking.
 
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Sure would be nice if Bill at Navworx or Neil (AllThumbs) would respond here on VAF and let the RV community know what is REALLY happening.

It may be that having lawyers involved (as was mentioned earlier in the thread) will really slow down (put on hold?) Navworx-customer communication on the issue. I'm in the proposed AD's EXP boat, having recently installed the unit with several hours' help from an A&P, so I'm anxious to hear what the remedy will be...but am also "on standby" as flightlogic aptly puts it.
 
FWIW, I was an early adopter and have been flying with my unit since last Oct.
I am very satisfied with all it's operations.

ADS600-EXP
SN:150643
PN:200-8013-01-01

My compliance report in Nov/2015 reported SIL=3.

Let's see what happens. I'm sure Bill will make it right. From what I understand, the TSO compliance was not an easy task.
 
Navworx

I tried several times yesterday to reach navworx by phone. It was no surprise that it went straight to their voicemail each time. As per the Navworx statement regarding the AD, I'd like to contact the FAA supporting my unit and Navworx. I really don't know what to say though. What have others said? I am a VERY satisfied navworx customer and my unit seems to function flawlessly. I don't really understand the SIL thing but what I've read it's the possible error in the horizontal plane. I'm wondering what that means. Are they talking a few feet or several hundred or is it strictly the number of times of a potential error per hour?
 
I tried several times yesterday to reach navworx by phone. It was no surprise that it went straight to their voicemail each time. As per the Navworx statement regarding the AD, I'd like to contact the FAA supporting my unit and Navworx. I really don't know what to say though. What have others said? I am a VERY satisfied navworx customer and my unit seems to function flawlessly. I don't really understand the SIL thing but what I've read it's the possible error in the horizontal plane. I'm wondering what that means. Are they talking a few feet or several hundred or is it strictly the number of times of a potential error per hour?

They're talking a few feet. What happened is the FAA spec guys were allowed to run wild. One new application of ADSB-out is to automate ground control. That's why wingspan is included in the data. To make sure large aircraft on adjacent taxiways don't clip wings, you need very good accuracy.
 
Sure would be nice if Bill at Navworx or Neil (AllThumbs) would respond here on VAF and let the RV community know what is REALLY happening.

Hi Marty. For once my procrastination in ordering the Navworx box paid off! This situation didnt come about overnight, and although Im sure there is a lot of scambling going on right now it won't get solved overnight. (Keep in mind there are lawyers involved.) Just hope that whatever the resolution to the situation turns out to be Navworx can suvive it and stay in business.
 
AF News GPS (without WAAS) provides 38 CM(14.9 inch) Accuracy

The NAVWORX certified units can use an external certified GPS source like a G430W Nav unit (SW Ver 5.0 or later). But give me a break, the AF said last April the GPS satellites are providing 15" accuracy without the FAA WAAS signal (see below). The WAAS signal increases accuracy to a few centimeters. So what is the FAA all bent out of shape over? This is Govt Bureaucracy at its Peak. Their begging the aviation community to equip with ADSB, and were fighting over likely the width of your hand in distance. It has been reported that modern GPS units like what is in the "non-certified" but demonstrated compliant NAVWORX WAAS GPS units have better processors and position algorithms than the now ~15 year old "certified" units. So it looks like the direction were on will take us all back in time, force us to downgrade to a FAA certified GPS source which of course will significantly increase cost.

Cecil

SCHRIEVER AIR FORCE BASE, Colo. (AFNS) -- On April 25 2016, the Air Force?s GPS registered its most accurate signal yet, according to the Aerospace Corporation, which has been monitoring the data since 2002.

Using the numbers from a network of NASA-owned, Jet Propulsion Laboratory-operated GPS tracking stations, Aerospace analysts calculated the signal-in-space accuracy of GPS to 38 centimeters (14.9 inches).

?The GPS team works around the clock to ensure we produce the most accurate signal available for our worldwide users,? said Lt. Col. Todd Benson, the 2nd Space Operations Squadron commander.

The squadron performs the command and control mission for the GPS satellite constellation, the world?s premier space-based position, navigation and timing system, capable of providing information to users worldwide.

According to Benson, the new record may be attributed to multiple improvements across the GPS enterprise.

?One improvement has been the outstanding GPS Block IIF spacecraft that have been acquired by the Space and Missile Systems Center and launched by the 45th Space Wing,? he explained. ?These 12 new satellites have enhanced the overall accuracy of the GPS constellation. Combine this with the retirement of older spacecraft, the rock solid performance of the previous block of satellites, and you have the opportunity to improve accuracy.?

He said another reason for the improvement has been the innovative approaches to operating the GPS mission.

?With the help of our engineers and contractor support, we were able to transition to a more stable frequency standard on a satellite to improve overall performance,? Benson said. ?Traditionally, this effort would have only happened if the original component failed. Our ethos is honed to maximize performance while maintaining a robust constellation."

Benson highlighted the GPS?s importance and why its accuracy is beneficial to its 3 billion users.

"GPS is embedded in almost every facet of modern life. From the swipe of a credit card to flying an aircraft around the globe, GPS enhances humanity's day-to-day activities," the colonel said.

PJ Mendicki, the Aerospace senior project engineer who calculated the record accuracy, echoed the sentiment. He stressed that the GPS has been the gold standard for Global Navigation Satellite System applications.

?The fact that GPS accuracy is continually exceeding the promises made in the 2008 Standard Positioning Service Performance Standard proves our nation's commitment to that standard,? he said. ?Through metrics like user range error, we can easily demonstrate that the nation's investment in this technology continues to pay dividends to all humanity, even though most are unaware of how pivotal GPS is to their daily life.?

(Some information compiled from Aerospace news release)
 
Note the "signal in space" phrase. Here on earth the signal must pass thru the ionosphere, where it does not travel at the speed of light in vacuum. This is where you need the waas correction.
There's also some averaging involved. Easy if you're not moving, a lot harder if you are.
But the bottom line is the FAA expanded the mission to include ground ops. That's where the very high positional accuracy is needed, not in flight.
 
"integrity" (the I in SIL) and "accuracy" should not be confused to mean the same thing... they are not.

"SIL specifies the probability of the actual position lying outside that containment radius without indication"
 
our rights on a proposed AD

Going back a few decades of flying, I can't help but remember Bob Hoover. When F. Lee Bailey decided to defend him... I thought "game over for the FAA". After a protracted battle, he won. Then became uninsurable.. so his airshow days were over anyway. The two men responsible for trashing one of the finest pilots in history cruised away quietly to retirement. In the Navworx proposed AD, there are two names and addresses given at the Ft. Worth ACO (Aircraft Certification Office) They hold tremendous power in the industry and operate under their own local judgement. There is no level playing field. That is why we have synthetic vision now. It went through the Anchorage ACO. Had it been in Ft. Worth, we probably would still be mired in research. Same could be said for Seattle.
The point here is this: We have names now. We have addresses now. They are out in the public domain. If you choose to give your concerns to the FAA, for hampering affordable ADS-B or. on the other hand, if you wish to applaud them for keeping you safer, you can and should write. We should hold our public employees accountable for their actions. We pay the bills and we use the airspace. Kyle Cobble and Michael Heusser. Addresses on are on the AD announcement.
 
Note the "signal in space" phrase. Here on earth the signal must pass thru the ionosphere, where it does not travel at the speed of light in vacuum. This is where you need the waas correction.
There's also some averaging involved. Easy if you're not moving, a lot harder if you are.
But the bottom line is the FAA expanded the mission to include ground ops. That's where the very high positional accuracy is needed, not in flight.

Bob, do you have a feed back link to FAA?

Just seems if ground clearance requirement could be amended to exempt light aircraft, problem would be over and small companies like Naxworx could get on with providing a reasonably priced system to meet the requirement.

I have a link to FAA regarding the rebate program, I was able to easily cancel reservation but not otherwise. I suppose the way to go would be to submit a comment regarding the proposed AD.
 
With regard to above, I just filed a comment with FAA and proposed AD.

It was easy, just go to first message this thread and do it after hitting AD link.
 
AD

The comments in the AD make some very interesting reading. If all 800 owners responded to the AD perhaps it would make a difference. Particularly on the financial impact. The $85 stated in the AD is ridiculous. The current AD will require us to replace the Navworx. Would be nice to hear from Navworx. Anybody been able to contact Navworx that has some proposed solutions?
 
I wouldn't worry too much about that. Bill is probably pretty busy right now. I have had the 600B for years and love it. I always thought that eventually I would pay for a certified GPS to go in the box. Getting the software that did it without changing the GPS was great but it doesn't seem insurmountable to remove and replace with a certified unit.

Options seem as follows (for my case):

1. Bill Moffett and FAA reach some sort of agreement and the proposed AD is withdrawn.

2. Box goes back to TX and certified GPS installed for a reasonable amount of cash. Bill cannot be expected to do this for nothing.

3. I use the serial port from the GNS480 with the Garmin ADSB+ output to input the certified position to the 600B. I can't use the ARINC 429 outputs because I am using both already to the GRT EFIS. I know this (or similar) option for the EXP is not feasible.

I think a solution will work itself out.
 
Model ADS600-EXP Part Number

I noticed the AD is applicable to Model ADS600-EXP P/N 200-8013. I just check my EXP order record from NavWorx and my part number is listed as 200-8012.

Does that mean the AD does not apply to my EXP unit?

What part number do you guys have on your EXP units?
 
Navworkx Response

I sent an e-mail today to Bill Moffit and asked why they ( Navworx ) have not had any response.

He replied promptly as follows:

We will be commenting in the next week or so as we?re still in talks with the FAA.

Best Regards,

Bill Moffitt
NavWorx Incorporated
888-628-9679
(972) 372-0768 (direct)
469-644-2459 (cell)
469-327-2683 (fax)
 
I sent an e-mail today to Bill Moffit and asked why they ( Navworx ) have not had any response.

He replied promptly as follows:

We will be commenting in the next week or so as we’re still in talks with the FAA.

Best Regards,

Bill Moffitt
NavWorx Incorporated
888-628-9679
(972) 372-0768 (direct)
469-644-2459 (cell)
469-327-2683 (fax)

Pretty much what I was expecting.

Makes sense, I am more than happy to wait for an answer based in knowledge and fact than in fear and speculation.
 
I met Bill at Oshkosh and came away favorably impressed. He has been using images of my 4 on his website to promote the Exp. units. When I teased him about the unauthorized use of my 4 he offered me a promotional rate on an Exp box. I took him up on the offer and the unit sets unopened in the box slated for install next month. Now not sure what to do except to wait and see if Bill finds a solution. I checked with my credit card company and they told me I have till Nov. 15th to dispute the charge. I'm not sure I'd take that option, I'd rather just wait for Bill to get back to us.
I was told by an avionics guru that there are only 3 companies that make the TSO'd GPS chips and they have raised their prices exorbitantly which led Bill to looking for an alternative. Seems like the big players in the avionics universe weren't too keen on Bill's affordable solution.
 
I just received my ADS600-EXP yesterday and it has a serial number 200-8013. I'm hoping it either has a necessary software change (SIL 0), or they've worked something out with the FAA. Either way - the FAA has received my comment on what I think of their unannounced change to their previously acceptable protocol.
 
I just received my ADS600-EXP yesterday and it has a serial number 200-8013. I'm hoping it either has a necessary software change (SIL 0), or they've worked something out with the FAA. Either way - the FAA has received my comment on what I think of their unannounced change to their previously acceptable protocol.


The problem is that if the SIL is changed to "0", the ground stations wont send traffic to it anymore. This started at the first of the year which prompted the change to SIL="3" to be able to receive traffic.
 
I just received my ADS600-EXP yesterday and it has a serial number 200-8013. I'm hoping it either has a necessary software change (SIL 0), or they've worked something out with the FAA. Either way - the FAA has received my comment on what I think of their unannounced change to their previously acceptable protocol.

Please let us know what SIL is reported on your 1st FAA ADS performance report. https://adsbperformance.faa.gov/PAPRRequest.aspx
 
No new info...

I go on vacation for a few weeks out of the country and this happens...

I have no info on this issue from Bill and, if there are lawyers and FAA involved, I'm not likely to get any info before you do. If he tells me something I can post, I will. But please remember I'm just a contractor who did an app to configure the EXP box and also, on my own time, help with west coast installation issues and answer VAF questions when able.

In the meantime I'd suggest everyone remain patient and not pelt Bill with questions he clearly won't, or can't, answer until the process has run its course.
 
Please let us know what SIL is reported on your 1st FAA ADS performance report. https://adsbperformance.faa.gov/PAPRRequest.aspx

This is meaningless. The SIL is not calculated by the FAA ground stations; it is programmed into the box by the manufacturer, and then sent out. As I understand the A/D - and I can easily be wrong - the FAA is saying that NavWorks was not authorized to put in SIL=3 into certain boxes using certain components.
 
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