ADS-B Out: Would you pay $700 more for 1090 ES over 978 UAT

Sam D

Sam D

Pattern Altitude
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Sam D
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Petaluma (o69)
Here's my dilemma -- how important is ADS-B transmission frequency?

1) In this corner, weighing in at $1,795 (not including installation), is the Garmin GDL 82.
2) And in this corner, weighing in at $2,495 (not including installation), is the Stratus ES.

Plane is a normally aspirated Lance - so no plans to go into the flight levels. However, every few years, there has been a trip to either Canada or Mexico (both of which will allegedly eventually require 1080). I was pretty much decided on the GDL 82 after OSH, but I keep thinking that the 978 may be limiting.

Thoughts?

Already have 430W installed. I "think" installation of both would be relatively straightforward. (Stratus ES would replace a Garmin GTX 327).

Thanks
 
another of my back and fore internal debates that keep me from buying.

Is it possible that 978 will be disallowed and put me in another (****ing stupid) mandate condition again?
You use the word allegedly quite well... what will Canada, Mex, and the Bahamas eventually settle on?

FL180 is higher than I need to be in my current flying.
 
If you're going to spend the money I'd bet on the more sure thing (1090). Especially since you've mentioned that international trips are part of the plan.
 
Canada, Mexico and the Bahamas are all going 1090. Canada has already announced it will be at least 10 more years before it will be mandated for private, non-commercial airplanes. And when it does finally come in, it will be satellite based so the antenna will be on the top of the plane.

I'd go with the UAT GDL 82 because I really don't think lack of 1090 ES is going to keep you out of the rest of North America for a long time to come.

However, one potential issue with the GDL 82 is I don't think it will come without the built-in WAAS position source, so that means it can't use your 430W as a source and you will have to put another WAAS GPS antenna on your plane.
 
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GRG55 said:
Canada, Mexico and the Bahamas are all going 1090. Canada has already announced it will be at least 10 more years before it will be mandated for private, non-commercial airplanes. And when it does finally come in, it will be satellite based so the antenna will be on the top of the plane.

I'd go with the UAT GDL 82 because I really don't think lack of 1090 ES is going to keep you out of the rest of North America for a long time to come.

However, one potential issue with the GDL 82 is I don't think it will come without the built-in WAAS position source, so that means it can't use your 430W as a source and you will have to put another WAAS GPS antenna on your plane.
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The Garmin guy I talked to at OSH seemed to suggest that you could use the existing antenna. That being said I don't think the installation manual has been released yet. And so the one shop I talked to was unwilling to quote labor.
 
I would wonder about the install costs of the GDL-82 as you have to install a GPS antenna somewhere. the 1090 would mainly involve rewiring the existing transponder wiring, and adding a single wire to the 430 for the GPS feed. Thing that suchs is that the 327 is a new and good transponder. This would be a no brainer if you still had a KT-76 or similar in there.
 
1090 is required above 18,000 ft or for international flying. If you intend to do either of those after 2020, the choice is obvious.
jon
 
4CornerFlyer said:
1090 is required above 18,000 ft or for international flying. If you intend to do either of those after 2020, the choice is obvious.
jon
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Where is it required for international (e.g. outside of the USA) flying of a private, non-commercial airplane after 2020?
 
vontresc said:
I would wonder about the install costs of the GDL-82 as you have to install a GPS antenna somewhere. the 1090 would mainly involve rewiring the existing transponder wiring, and adding a single wire to the 430 for the GPS feed. Thing that suchs is that the 327 is a new and good transponder. This would be a no brainer if you still had a KT-76 or similar in there.
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The -82 can use his existing 430w for position source. A little more wire to run but that's about it for installation differences.
 
Clark1961 said:
The -82 can use his existing 430w for position source. A little more wire to run but that's about it for installation differences.
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Interesting... Their specs on the web are very "lacking", and I cannot find an install manual anywhere online. JOOC, where did you get that bit of info from???
 
Gotcha! That would actually simplify an install considerably.
 
I'm not seeing any other reference that shows the GDL-82 being able to use an existing GPS source. Everything points to using its own internal GPS. Nor are they offereing a kit that exludes the internal GPS.


(That ad does say that tho)
 
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It's not very obvious, since all that is out there is just Marketing crap :-(

But I found this on Beech Talk from someone supposedly from Garmin

OK, got the skinny on this. to be honest with you I was going from some input received and had not actually seen a manual on it as of yet. so touched bases with our engineering team on it and the GDL 82 does have the inputs to it to connect via an RS 232 input from another approved GPS source which would eliminate the need for an additional WAAS
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https://www.beechtalk.com/forums/viewtopic.php?f=21&t=140880&start=15
 
I keep looking for GFC500 stuff but nope, its basically been crickets since it was announced.
 
I'd be tempted to swap those old ass KT76A and Narcos for a GTX327, they are about $400 used. Thats about $2200 with GLD82, well under the price of the GTX335 with internal GPS. Unless there is a rebate on one vs the other then that might sway it in favor of the 335.
 
bnt83 said:
I'm not seeing any other reference that shows the GDL-82 being able to use an existing GPS source. Everything points to using its own internal GPS. Nor are they offereing a kit that exludes the internal GPS.


(That ad does say that tho)
Click to expand...

I hope this reading of the advert is correct, as it would be a far less expensive solution than replacing my transponder with a GTX 335 or 345. That is one reason I am suspicious, as I cannot see Garmin deliberately cannibalising sales of these two relatively new ADS-B directed products.

However when I read it I think the wording can be interpreted more than one way. It is not really clear the GDL-82 itself will accept an external WAAS position source. The way its worded is that the ADS-B requirement for position source could be met with an existing WAAS source...or one could install a GDL-82 with its internal WAAS source and antenna instead.

Anybody got a connection at Garmin that can answer that question definitively. I have asked my Garmin dealer here to see what they can find out.
 
GRG55 said:
I hope this reading of the advert is correct, as it would be a far less expensive solution than replacing my transponder with a GTX 335 or 345. That is one reason I am suspicious, as I cannot see Garmin deliberately cannibalising sales of these two relatively new ADS-B directed products.

However when I read it I think the wording can be interpreted more than one way. It is not really clear the GDL-82 itself will accept an external WAAS position source. The way its worded is that the ADS-B requirement for position source could be met with an existing WAAS source...or one could install a GDL-82 with its internal WAAS source and antenna instead.

Anybody got a connection at Garmin that can answer that question definitively. I have asked my Garmin dealer here to see what they can find out.
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See post 17
 
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GRG55 said:
"...from someone supposedly from Garmin"

I need something a bit better than that before I shell out any of my cash.
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You've got plenty of time since the unit won't be available until November and the STC will have to be approved before that.
 
GRG55 said:
Unless one wants to fly IFR in Australia, there's nothing on that list that would appear to compel a US-based owner of a private, non-commercial airplane flying below 18,000 ft to install 1090 ES.

The whole list has the tone of AOPA trying to rationalise throwing its support behind forcing every 172/Cherokee/J-3 Cub owner spend a bunch of money.
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I think the Mexico part will stop a most airplanes without 1090

"Mexico. 1090ES required beginning January 1, 2020, in Class A, B, C, E above 10,000 feet msl, and other specified airspace. Requirement takes effect January 1, 2018, in Class E airspace over the Gulf of Mexico, at and above 3,000 feet msl within 12 nm of the Mexican coast."
 
Sam D,

In your situation and given some of the info presented regarding existing GPS sources, I think I would lean towards the GDL 82. Your GTX 327 should provide good service for the foreseeable future and 978 should give you everything you need. I would think GDL 82 installation would be cheaper than the Stratus ES.

I actually recently struggled with a similar decision, GDL 82or Stratus ESGi and decided to go with a Stratus ESGi as I have an aging KT76 that failed certification had to be replaced. Additionally my aircraft is /A with no GPS source and aging avionics.

The only other consideration is whether you want to get in on the $500 rebate which I just learned is apparently taxable so more like $300 in pocket...
 
A aircraft is a traveling machine, stripping some of the international ability is silly.

That said I'd look into the dual band navworx box that they are coming out with, with in, out, wifi and stealth mode.

You still have years before you need ADSB, it would be smart to wait and let the features go up and the prices go down.

http://www.navworx.com/
 
I don't think there is any 1090 out solution that offers anonymity. Several of the 978 do.
 
Remember Mode S will also broadcast your hex id. You gotta be Mode C to be anonymous using a 978 system :D
 
bnt83 said:
I don't think there is any 1090 out solution that offers anonymity. Several of the 978 do.
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I thought that was by design? I don't think Anon is permitted on 1090.
 
I went with the 1090 solution by swapping my Garmin GTX 327 Mode C transponder for a Garmin GTX 335 Mode S transponder with extended squitter. I'm very weight conscious and try to keep my plane light to maximize it's utility for backcountry flying. Going with the Mode S transponder was weight neutral for me. The 335 weighed the same as the 327 it replaced and it ties to my 430 for the WAAS GPS signal. Going with the UAT solution would have required an additional box, adding weight and adding it in the rear of the plane shifting my CG aft. It was easy for me too decide the extra money for 1090 was well worth it.
 
The TSOs only allow 978 UATs to have anonymity (mode). The Garmin GDL-88 in my Dad's 182 shows directly on the screen (GTN) a button to activate anonymous mode. The associated GTX-327 is just a plain old one that doesn't know or transmit identity.

My GTX-345 will allow only disabiling of 1090ES. I don't think that gives me anonymity
 
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bnt83 said:
...My GTX-345 will allow only disabiling of 1090ES. I don't think that gives me anonymity
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?? o_O

I thought the GTX 345 transmitted ADS-B ES on 1090 only? If you "disable" it what happens?
 
GRG55 said:
?? o_O

I thought the GTX 345 transmitted ADS-B ES on 1090 only? If you "disable" it what happens?
Click to expand...

You are just Mode S. The ES is just additional data that is transmitted as part of the Mode S reply. That is what is left off if you disable the ADS-B.
 
GRG55 said:
?? o_O

I thought the GTX 345 transmitted ADS-B ES on 1090 only? If you "disable" it what happens?
Click to expand...

I wanted to find out what exactly was transmitted in "1090ES disabled mode" when my friend was up there with transponder test set but forgot to do so. Next time I'll check it.
 
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