NavWorx Unit Removal AD

[Piloto]

As per FAA proposed AD https://www.federalregister.gov/documents/2016/10/20/2016-25255/airworthiness-directives-navworx-inc-automatic-dependent-surveillance-broadcast-universal-access?utm_campaign=subscription mailing list&utm_source=federalregister.gov&utm_medium=email

It will require the removal of the NavWorx ADS-B transceivers due to possible wrong position information transmitted.

I do not have ADS-B in my plane but when is time to install I would prefer a solution were I can confirm the GPS position in a moving map such as a in GNS 530W or GNS 750 or IFD 540.

José

 

 

[mike_elliott]

The L3 Lynx 9000 is a self contained all inclusive unit that displays position on itself and will push it out to an Ipad. Feature for feature, very hard to beat imo.

[takair]

Too bad.  It was near the top of my list. It would display traffic on my 430 and iPad.  That said, I know the FAA was questioning their TSO and was withholding any rebates.  This pretty much explains why.  

[Raptor05121]

So far, it is proposed only and is up for discussion. It appears that they switched to non-compliant GPS receivers and the FAA says the current setting takes them out of compliance. It looks as if a swap of GPS receiver in the unit OR changing some programming to get a tighter tolerance will bring it back into compliance.

I am paying very close attention to this as I am eyeing the ADS600B unit for my install.

[takair]

Just scanned the AD.  Seems a little aggressive.  I would think that the unit could be disabled until a software fix comes, since it was a recent change that caused the problem.  Also, I'm sure some installations use an external GPS.  Will be curious what the comments look like against the AD.

[Raptor05121]

What the FAA is saying:

NavWorx produces ADS-B units under Technical Standard Order (TSO) C-154c. NavWorx has implemented a design change by revising its software for ADS-B units, Model ADS600-B part number (P/N) 200-0012 and 200-0013 and Model ADS600-EXP P/N 200-8013. The design of the units includes an internal uncertified GPS source. ADS-B units with an uncertified GPS source are required to broadcast a SIL of 0. The software revision (version 4.0.6) resulted in the units broadcasting a SIL of 3. This design change was not approved by the FAA and rendered the units noncompliant with TSO-C154c. Because the ADS-B unit incorrectly broadcasts a SIL of 3 instead of 0, the unit could communicate unreliable position information to ATC and nearby aircraft, resulting in an aircraft collision.

What the president of NavWorx is saying:

The FAA has proposed an AD for our model ADS600-B part number (P/N) 200-0012 and 200- 0013 and Model ADS600-EP P/N 200-8013. The proposal is just that; a proposal. We disagree with the FAA’s positon that the units supposedly communicate unreliable position information. 

The FAA has never shared with us any instance of our units doing so, there is no support for this claim in the docket, and we are unaware of any unit doing so. In fact, for two and a half years the FAA had no problem with the ability of our units to correctly communicate the position of aircraft with the units. 

Unfortunately, in January of 2016 the FAA would have cut off functionality of these units because they were broadcasting a SIL of 0. This action was the result of a March 2015 notice to deny TIS-B access to ADS-B units that were uncertified and broadcasting with a SDA of 0. The units subject to the proposed AD are neither uncertified nor do they broadcast with a SDA of 0. 

To insure continued access to TIS-B data we implemented a minor change so the units would broadcast a SIL of 3, which our testing had confirmed was appropriate, allowing them to continue to be identified for TIS-B purposes. The proposed AD would deny these units access to TIS-B data. 

We intend to file comments on the proposal and would encourage you to do likewise regarding your experience with our units. In the meantime we continue to work with the FAA to resolve our disagreements.

[Piloto]

One weakness of ADS-B is the integrity of the GPS position data. If the GPS position is wrong the traffic on your display is wrongly located and yours on that of the traffic's display. Conventional TCAS systems do not have this issue since they do not rely on GPS but on your old trusty Mode C transponder.

José

[glafaille]

Seems a little late in the game to be having these problems.  The FAA is not instilling confidence in me to the point that I am interested in spending the money to comply.

Heck, the system is not even required equipment today and yet they are demanding folks REMOVE the system.

Remember gents that once you install ADS-B out, it must be on at ALL times, even on the ground.

[Mooneymite]

Just a great example of why I'm never first in line for any FAA mandated install.

Look for me near the end of the line.  If I get grounded for awhile, so be it.

[N201MKTurbo]

So I did a little research and the NavWorks and other ADS-B out systems have not proven that they are reliable enough to have an SDA number higher than 0. Up until about a year ago if the FAA system received any ADS-B transmission it would reply with traffic information for that area. For the last year the FAA has been ignoring any ADS-B transmission with an SDA number less than 3, so the NavWorks system would not trigger traffic broadcasts.

In a recent software update they just hard coded an SDA number of three without actually meeting the standard for a 3. This clearly violates the regulations.

I'm kind of with the FAA on this one.  

[glafaille]

Seems to me that at this point, a few years out from mandatory compliance, the FAA should be working WITH the manufacturers to develop equipment that will encourage maximum compliance at affordable prices.

Heavy handed enforcement does little to encourage manufacturers to improve products and prevents start up manufacturers from bringing new products to market.

One only needs to watch how this plays out to understand why everything related to aviation is so expensive and product development so slow.

[N601RX]

I've had an uncertified portable SkyGuard unit for a few years that up until last January was sending out a zero. In January they were allowed to upgrade their software to send something greater than zero but less than 3.   This allowed them to continue to trigger traffic updates. 

[jetdriven]

9 hours ago, Piloto said:

One weakness of ADS-B is the integrity of the GPS position data. If the GPS position is wrong the traffic on your display is wrongly located and yours on that of the traffic's display. Conventional TCAS systems do not have this issue since they do not rely on GPS but on your old trusty Mode C transponder.

José

TCAS systems actually use air data and when they go into RA mode, they communicate with each other. 

[PTK]

They violated regulations and the FAA called them out on it. 

Not the FAA's problem and it's not a discussion about product cost and development etc etc.

Just follow the regulations instead of playing victim.

[glafaille]

4 hours ago, PTK said:

They violated regulations and the FAA called them out on it. 

Not the FAA's problem and it's not a discussion about product cost and development etc etc.

Just follow regulations instead of playing victim.

Few issues involving the FAA are as "Cut and Dried" as you seem to think.  

[glafaille]

And by the way, it is indeed the "FAA's Problem" if the majority of aircraft in the USA are NOT compliant by Jan 1st 2020.  They are well aware of this and are offering rebates in an effort to increase the level of compliance.  I expect they will up the ante as we get closer to 2020.

[mooniac15u]

On 10/21/2016 at 3:17 PM, glafaille said:

Remember gents that once you install ADS-B out, it must be on at ALL times, even on the ground.

I don't think that's true.  Can you point to a regulation or an AC with that guidance?

[glafaille]

1 hour ago, mooniac15u said:

I don't think that's true.  Can you point to a regulation or an AC with that guidance?

FAR 91.225 (f) requires the equipment to be in transmit mode at ALL times.

FAR 91.225 (f) (1) Allows you to continue to your ultimate destination if the equipment becomes  inop enroute.  Otherwise I believe you are grounded with inop ADS-B out if installed.

AC 20-165B Paragraph 2.2.2.5 Says the ADS-B out equipment should be on at all times even on the ground and not turned off after landing like we normally do with transponders.

Although ACs are not mandatory, the equipment is designed and installed to meet the guidelines in the AC.

So the way I see it, if you install ADS-B in your aircraft it must be on and operating for you to legally operate the aircraft, ground or air, UNLESS you are completing a flight or series of flights to your ultimate destination OR taking the aircraft somewhere to get the ADS-B repaired.

ADS-B becomes as much a required piece of equipment as your oil pressure gauge once you install the system.

i think this is why the FAA is proposing, in the AD concerning certain Navworks ADS-B installations, that the equipment be REMOVED instead of disabled.  If it's removed you can continue to fly if it's disabled you can't.

[glafaille]

AC 20-165B Paragraph 3.7.2.2 confirms the requirement in FAR 91.225 that ADS-B out equipment must be on at all times if installed.

[takair]

But doesn't 91.213 continue to provide "an out"?  I believe it does.

[glafaille]

FAR 91.213 pertains to operations with inoperative equipment under an approved MEL.

Do you have an approved MEL for your aircraft?  Does it allow you to fly with an inoperative ADS-B out system?  I doubt it.

I do have sn approved MEL for the aircraft I fly professionally, and it gives no allowance for operations without ADS-B if installed.  Furthermore, I have asked the FAA about this issue and have not yet been able to find anyone that knows the answer.

The company that writes our MEL doesn't know either, but they do say that when they add ADS-B, the addition will have to comply with 91.225 and 91.227.

The bottom line is that I don't think 91.213 allows you to deviate from 91.225 and 91.227.  The ADS-B system must be working at ALL times.

Perhaps someone else can get better info from the FAA.

[takair]

3 hours ago, glafaille said:

FAR 91.213 pertains to operations with inoperative equipment under an approved MEL.

Do you have an approved MEL for your aircraft?  Does it allow you to fly with an inoperative ADS-B out system?  I doubt it.

I do have sn approved MEL for the aircraft I fly professionally, and it gives no allowance for operations without ADS-B if installed.  Furthermore, I have asked the FAA about this issue and have not yet been able to find anyone that knows the answer.

The company that writes our MEL doesn't know either, but they do say that when they add ADS-B, the addition will have to comply with 91.225 and 91.227.

The bottom line is that I don't think 91.213 allows you to deviate from 91.225 and 91.227.  The ADS-B system must be working at ALL times.

Perhaps someone else can get better info from the FAA.

Actually, 91.213(d) covers aircraft without an MEL.  Section d1 covers out non-turbine powers airplane, d2 describes what may be inoperative, and d3 covers what you must do.  This section is used quite frequently in part 91 flying and it would be a significant burden on the industry if this went I away.  You would technically need a ferry permit every time something broke.  I wouldn't be surprised if the wording is changed in the final AD.

Not sure what aircraft you fly professionally, but the transport category aircraft I am familiar with do have the ability to MEL the ADS-B provided their is alternate means of flying the airspace.  This should be no different than MELing the transponder.  

[glafaille]

This part of 91.213 may be a problem:

(2) The inoperative instruments and equipment are not—

(iii) Required by §91.205 or any other rule of this part for the specific kind of flight operation being conducted;

As ADS-B is required in 91.225 to be on at all times it seems that this section of 91.213 does not provide relief.  

 

[takair]

1 minute ago, glafaille said:

This part of 91.213 may be a problem:

(2) The inoperative instruments and equipment are not—

(iii) Required by §91.205 or any other rule of this part for the specific kind of flight operation being conducted;

As ADS-B is required in 91.225 to be on at all times it seems that this section of 91.213 does not provide relief.  

 

I think 91.225(g) provides some level of relief for operation, while taking advantage of 91.213.  I agree 91.225(f) makes it rather compelling, but I believe the intent is stil for post 2020 flying...and even then, they need to provide relief like they do for transponders. 

[glafaille]

As I read 91.225(g), the only relief you get is to continue your flight or series of flights to your ultimate destination and/or to fly the aircraft somewhere to get the ADS-B system repaired.  

Pretty cut and dried.  Either you fall into one of those two exceptions or you don't fly or even taxi.

As to the intent of all this to be enforced only post 2020, I received an email from AOPA several months ago warning members that the FAA was currently investigating and threatening enforcement against people that HAD ADS-B installed but the equipment was not functioning properly.

The AOPA suggested that anyone receiving any inquiry from the FAA concerning their ADS-B system, contact the AOPA legal defense department before responding.  Here we are 3 years out and it seems the FAA is already taking a hard line. (Navworks another example?)

I believe that to stay out of trouble with the FAA you should first, avoid installing the equipment unless your operation absolutely demands it.  Second, if you have it installed, don't fly or even taxi across the airport unless you are certain it's on and operating.  And third, contact the AOPA legal defense folks if you get a friendly letter from your FSDO.

I am not encouraged by these events and will not be standing in line to install in my aircraft.  I think I can survive by avoiding Class A, B and C airspace, as well as staying below 10,000 ft after 2020.