Possible AD for certain NAVWORX ADS-B Units

[Brantel]

Originally Posted by rvator51

I wonder if a compromise solution that Navworx could change the software to broadcast SIL=1, which would make everyone happy and give Navworx and the FAA 4 years to come to agreement/solution on getting the SIL=3, while the user can still get traffic?

Except that breaks the rules and is unfair for the rest of the manufacturers that have followed them...

[rvator51]

Originally Posted by Brantel

Except that breaks the rules and is unfair for the rest of the manufacturers that have followed them...

This is what Dynon is doing with their uncertified GPS source antenna on the Skyview system, I think. My understanding is that when the new certified GPS source is added, then the SIL changes to 3. So not sure if unfair or not. Isnt SIL=1 for uncertified GPS sources?

[lr172]

Originally Posted by Jordan1976

This AD is for a TSO'd unit. From the AD:

If you go further in that paragraph, you find:

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.

Clearly the proposed AD will affect both the B and the EXP.

What I don't understand here is the FAA's statement that a TSO'ed GPS chip is required. I was under the impression that a year ago, the FAA gave manufacturers the right to use non-TSO'ed components that met the performance requirements of the TSO. They failed to mention that this would require a SIL=0, thereby rendering the product useless in 2020. I have a feeling this a new revelation to unwind what they initially offered.

Larry

[Mich48041]

The location of the GPS antenna on the aircraft can vary from plane to plane, perhaps 10 feet or more. So what difference does it make if the GPS position is accurate to within 10 inches or 10 feet? If a GPS receiver provides a position that is accurate to within 10 cm, but the antenna is located 10 feet off center, the ADS-B location of the aircraft will be 10 feet off. Is that dangerous? ATC usually provides 3 miles or more of separation between aircraft. The accuracy of even the cheapest GPS is a very small fraction of 3 miles. The argument has been made that very accurate GPS is needed for airport taxi operations. Really? What controller would issue taxi instructions that would allow aircraft to miss each other by a few inches?
Shouldn't the mission of the FAA be to improve safety, not to hinder it? It reminds me of a country to our south where the police are ones committing the crimes.
Regulations, that deprive pilots of traffic information and force manufactures to increase prices, do not contribute to safety. They are immoral.

[Radomir]

Funny that you mention that.. there are transceiver settings related to antenna position (offset from centerline of aircraft) to account for exactly the issue you're mentioning. So they already got that covered...

[BobTurner]

As posted above, your ADSB-out is supposed to broadcast wingspan, length, and GPS antenna position when you're on the ground. And in the FAA's vision of the future, no controller will issue ground instructions - a computer will.
Make no mistake, ADSB is all about saving the FAA money, and keeping GA out of the way of the airlines. Traffic and wx are just the 'carrot' to make the 'stick' ($$) seem more palatable.

[Brantel]

Originally Posted by rvator51

This is what Dynon is doing with their uncertified GPS source antenna on the Skyview system, I think. My understanding is that when the new certified GPS source is added, then the SIL changes to 3. So not sure if unfair or not. Isnt SIL=1 for uncertified GPS sources?

You can earn a TSO for SIL-anything. You can properly test/demonstrate to SIL-anything.

You can't just transmit SIL > 0 without demonstrating or earning the TSO to SIL-1 thru 3 which is what the FAA seems to be complaining about.

As far as I know neither Garmin or Dynon do this.....(output SIL > 0 without following the rules)

[aerovin]

Originally Posted by lr172

I was under the impression that a year ago, the FAA gave manufacturers the right to use non-TSO'ed components that met the performance requirements of the TSO. They failed to mention that this would require a SIL=0, thereby rendering the product useless in 2020. I have a feeling this a new revelation to unwind what they initially offered.

I keep seeing this as an 'impression' but does anyone actually have a source document that says this? It's not private information...it would be in some FAA document/AC/Order somewhere.

[lr172]

Originally Posted by aerovin

I keep seeing this as an 'impression' but does anyone actually have a source document that says this? It's not private information...it would be in some FAA document/AC/Order somewhere.

you should check out this new thing they call Google. Here is a press article about it. Didn't feel like digging deeper to find the actual FAA doc.

http://generalaviationnews.com/2015/...er-cost-ads-b/

[BHunt]

Does Navworx have any sort of EAA backing in this?