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G5 as gps waas!

Rakan

Active Member
I was reading about the installation of the G5 nonTSO, where it says that the G5 has a built-in GPS receiver and antenna and when connected to GA35 gps waas antenna it would provide a highly accurate ground speed and ground track readout.
with that in mind, can I use the G5 as position source for GTX330ES!!

I made copy and past diagram, from G5 and GTX330ES manuals, I am not sure if it is accurate or not...
I appreciate the feedback from all ... thanks
 
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Hi Rakan,

The GPS WAAS receiver in the G5 meets VFR standards and does not comply with the FAA specification for an approved WAAS positions source for ADSB. In this case you would need to use a GPS20A.

Best Regards,

Brad
 
thanks Brad for the reply...
the question is would G5 provide gps waas position when connected to the GTX330ES ,,, would such retrofit work ... hypothetically :)
 
G5 GPS Receiver

thanks Brad for the reply...
the question is would G5 provide gps waas position when connected to the GTX330ES ,,, would such retrofit work ... hypothetically :)

The GPS receiver built into the G5 does not meet the minimum requirements to qualify as a GPS position source for ADS-B purposes, as defined by FAA regulations. When an ADS-B transponder is using a non-qualifying GPS source, it is flagged in the ADS-B system and a notification of violation is promptly generated by the FAA.

Thanks,

Justin
 
The GPS receiver built into the G5 does not meet the minimum requirements to qualify as a GPS position source for ADS-B purposes, as defined by FAA regulations. When an ADS-B transponder is using a non-qualifying GPS source, it is flagged in the ADS-B system and a notification of violation is promptly generated by the FAA.

Thanks,

Justin

thanks Justin for the reply and the info ... so no go for G5 .. as GPS waas source:rolleyes:
 
For the use you are asking/intending this for.... A no-go for WAAS position source to a transponder. It would not provide any usable/working benefit.

BR,
 
thanks Brad for the reply...
the question is would G5 provide gps waas position when connected to the GTX330ES ,,, would such retrofit work ... hypothetically :)

Your diagram shows the G5 connected to a GA35 WAAS antenna which is providing the WAAS source, not the G5's internal antenna.
 
Your diagram shows the G5 connected to a GA35 WAAS antenna which is providing the WAAS source, not the G5's internal antenna.

yes according to the G5 manual if you do not have GPS waas source you could connect the unit to GA35 as an alternative.
 
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Hi Rakan,

The GPS WAAS receiver in the G5 meets VFR standards and does not comply with the FAA specification for an approved WAAS positions source for ADSB. In this case you would need to use a GPS20A.

Best Regards,

Brad
While we're discussing the GPS20A - now our NAA has come out and said we can use low-cost avionics for ADS-B, with uAvionix getting approval off the bat, it's got me wondering about Garmin and Dynon's offerings.

To use a G3X or SkyView system (now we can do so legally), the GNSS position source needs to meet the performance standards of TSO-C196 (or 145/6 for a navigator)- but doesn't actually have to be TSO'd.

Dynon has published their's meets TSO-C166 and FAR91.227, but what standards does the GPS20A meet - I can't seem to find any documentaiton on the Garmin site.
 
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The GPS 20A meets the standard. But it is not TSO'd for use in certified aircraft. As such it is for use in experimental aircraft only here in the USA, just like the uAvionix Echo.

So it sounds like the Aussies get it. Think about it, imagine two aircraft shooting conventional ILS instrument approaches to minimums to parallel runways at the same time. One is an experimental aircraft with a GPS 20A providing WAAS to an Echo, a Stratus Transponder or Garmin GTX x35(r), and the other aircraft is a type certified aircraft with a TSO'd WAAS source providing position information to a GDL 82, Stratus Transponder or GTX x35(r). How could there be a real problem between the two sources if they are allowed to fly next to each other in IMC? Just because one says Experimental on the panel doesn't mean it's not as safe to be right next to another aircraft that doesn't say Experimental on the panel. So why the big hang up between "meets the standard" and "is TSO'd"? Even LSA's properly equipped can fly in IMC under an instrument flight plan in the same airspace as airliners.
 
The GPS 20A meets the standard. But it is not TSO'd for use in certified aircraft. As such it is for use in experimental aircraft only here in the USA, just like the uAvionix Echo.

So it sounds like the Aussies get it. Think about it, imagine two aircraft shooting conventional ILS instrument approaches to minimums to parallel runways at the same time. One is an experimental aircraft with a GPS 20A providing WAAS to an Echo, a Stratus Transponder or Garmin GTX x35(r), and the other aircraft is a type certified aircraft with a TSO'd WAAS source providing position information to a GDL 82, Stratus Transponder or GTX x35(r). How could there be a real problem between the two sources if they are allowed to fly next to each other in IMC? Just because one says Experimental on the panel doesn't mean it's not as safe to be right next to another aircraft that doesn't say Experimental on the panel. So why the big hang up between "meets the standard" and "is TSO'd"? Even LSA's properly equipped can fly in IMC under an instrument flight plan in the same airspace as airliners.

Not that I don?t agree with you, but

Garmin G3X and Dynon systems need a TSO?d GPS navigator (or VOR, etc) to fly IFR. They are not IFR as stand alone systems.
 
The GPS 20A meets the standard. But it is not TSO'd for use in certified aircraft. As such it is for use in experimental aircraft only here in the USA, just like the uAvionix Echo.

So it sounds like the Aussies get it. Think about it, imagine two aircraft shooting conventional ILS instrument approaches to minimums to parallel runways at the same time. One is an experimental aircraft with a GPS 20A providing WAAS to an Echo, a Stratus Transponder or Garmin GTX x35(r), and the other aircraft is a type certified aircraft with a TSO'd WAAS source providing position information to a GDL 82, Stratus Transponder or GTX x35(r). How could there be a real problem between the two sources if they are allowed to fly next to each other in IMC? Just because one says Experimental on the panel doesn't mean it's not as safe to be right next to another aircraft that doesn't say Experimental on the panel. So why the big hang up between "meets the standard" and "is TSO'd"? Even LSA's properly equipped can fly in IMC under an instrument flight plan in the same airspace as airliners.

It's the FAA--it doesn't have to make sense. But part of it is a quirk of ADS-B installation rules, and the general rules for installing equipment on certified aircraft. Look up AFS-360-2017-1

Short story is, the FAA generally only requires "meets the standard" for ADS-B equipment and position sources, regardless of aircraft. But getting the approval to install the equipment is a different matter.

In general, installing something on a certified airplane usually means either getting an STC, or installing TSO'ed equipment (see Part 21). The FAA has issued guidance specific to ADS-B equipment to expedite installation. Provided the "initial equipment pairing approval" for position source and ADS-B Out device has been approved via TC or STC (on any aircraft), subsequent aircraft can install that equipment pair via 337 without specific approval, provided a few other conditions are met. It still does not directly absolve the need for a TSO'ed GPS unit of some kind, by a strict read of the policy (see item 3.b of the document listed above, although that sort of contradicts the flowchart later on where it says "meets the performance requirements of..."). I think this may have been an oversight?

However, note that an STC allows you to basically bypass the requirement for a TSO. If you can get an STC applicable to your aircraft that covers the pairing of your non-TSOed position source and non-TSOed ADS-B unit, you're good to go. That's how Dynon is able to use the Skyview GPS for ADS-B out--they obtained an STC including that equipment.


Technically, I don't think IFR navigation strictly requires an actual TSO, either; I think there's a provision for "meets the performance requirements" there, too. But those requirements go beyond just position and into things like database integrity, correctly computing routes, etc. So far, nobody* has come out with an IFR navigator that meets those requirements but isn't TSOed. I think that's a market thing--the market for non-TSOed ADS-B is big, because it can cover almost any aircraft, certified or experimental, IFR or VFR. But for all practical purposes, a non-TSOed IFR GPS would be limited to IFR homebuilts--a much smaller market with a smaller proportion of IFR-equipped aircraft. By getting the TSO, you get much easier installation on a much larger market.

*GRT is working on it, apparently, but no indication of when it will be ready...
 
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from the reading, WAAS is not required for the ADS-B mandate. ADS-B does require a precise positioning source, such as the Global Positioning System (GPS).
The Question, can non waas garmin gps 400 provide the minimum to comply to the ads-b mandate taking into consideration waas stations mostly found in the United states (for the time being).
 
The FARs just say ?position source?. But the specifications call for extreme accuracy - accuracy that can only be met by gps with WAAS. Non-WAAS isn?t good enough. (The extreme accuracy requirement-so tight that you have to broadcast your antenna position wrt the nose of the airplane-are all due to the anticipated use of adsb for automated ground control).
 
Not that I don?t agree with you, but

Garmin G3X and Dynon systems need a TSO?d GPS navigator (or VOR, etc) to fly IFR. They are not IFR as stand alone systems.

He said ?shooting an ILS approach? which doesn?t require a GPS...

Skylor
 
Yes. A conventional ground-based ILS approach in the soup. Yet the respective ADS-B compliant equipment in the EAB and the Type Cerified are still equal for purposes of separation and safety, both air and ground. One officially TSO'd and the other merely meeting or exceeding the TSO requirements.
 
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