Bacho
Pre-takeoff checklist
I am a new owner of a 172G, I am exploring my ADS-B options as well as considering an IFR GPS. So far I have not found the 175 as an approved position source for an ADS-B transponder. Is there something I am missing?
Garmin 175 as a position source.
- Thread starter Bacho
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denverpilot
Tied Down
There is a minimum TSO they have to meet.
Bacho
Pre-takeoff checklist
Ok, so this list is exclusive correct?
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denverpilot
Tied Down
Its not the complete list of GPS sources that would qualify but probably the most common you’d see in a GA fleet.
Also certainly up to the manufacturer of the device receiving the GPS data if they want to put limitations on it and what they submitted for approval for their paperwork.
The doc is from February. If you had some other GPS source in mind, you could always call Appareo and ask. I don’t think anything significant has been released this year other than the Garmin that already has the ADS-B stuff built in.
Bacho
Pre-takeoff checklist
Good deal, Thanks for the help.
The GTX 335 transponder has GPS but I don't think it can be the source for the Appaero.
These are the FAA approved ADS-B Out / GPS combinations for certified aircraft: https://www.faa.gov/nextgen/equipadsb/installation/equipment/
Now, one could conceivably strike out on their own and get approval for other combinations following the guidance of Advisory Circular AC 20-165B in addition to other "hoop jumping."
Now, one could conceivably strike out on their own and get approval for other combinations following the guidance of Advisory Circular AC 20-165B in addition to other "hoop jumping."
And the 175 is on the list"
Garmin GTN 625/635/650, GTN 725/750, GIA 63W , S 430W/430AW/480/530W/530AW, GPS 175, GPS 400W/500W (w/ or w/o TAWS) (all require appropriate S/W rev)
AK737pilot
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Chris
Something you might check into is if the 175 can use the position data from a GTX 335. I have a 335 (with its own WAAS antenna) with a stub out RS-232 pair and hope to one day use for a G5.
Could the RS232 feed a 175?
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Could the RS232 feed a 175?
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I had the 335 installed a couple years ago, the G5 a couple months ago. Use the same GPS antenna. The A&P who installed the G5 checked the installation manual, and the RS232 goes to the G5. As for the 175....that requires a second GPS antenna, as per the avionics shop on the field.
denverpilot
Tied Down
And that’s why I suggested talking to Appero. The 175 only started offering WAAS in March. The doc is labeled Feb.
The problem is the manufacturers also get to say what combinations are tested and happy with their “easy” install docs. Something else may require more/different paperwork to show it’s a working combination.
bnt83
Final Approach
What transponder specifically?
Bacho
Pre-takeoff checklist
No specific choice yet. Right now I have a KT76, skybeacon was my first choice. However I got a good reminder of my transponders age the last couple flights. It seems spending more a little now would be smarter than installing the skybeacon or gdl-82 with my old transponder. So I started looking at the ESG or 335 which are better options for me IMO. But if I was to go with the 175 now instead of later, I could save a few bucks on something like the stratus ES for example.
I have an A&P and want to do my own work. The 375 is out.
Jesse Saint
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You could just hook the existing gps antenna to the 175 and RS232 our from the 175 as position for the 335. The 335 can either use internal gps or an external position source. Same result, but a different way to get there.
MBDiagMan
Final Approach
Sounds like a 375 would be the obvious choice.
Groundpounder
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Emerson Bigguns
Let say you have a GPS-175, and a GNC-255. Is there enough communication between the two that the GNC-255 will auto tune an ILS if you have an ILS programmed into the GPS-175?
Chip Sylverne
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Quit with the negative waves, man.
Can't speak to auto tune, but the 175 does tx via RS232 to the GNC 255 in aviation format. So my guess is the freqs would display and you select what you want.
Bummer it doesn't communicate with an SL30.
unsafervguy
En-Route
if you have an old transponder, need adsb and want a ifr gps seems to me the best solution is the 375.
Bacho
Pre-takeoff checklist
I bought a stratus ESG from Jim. A product I could install myself was a big deal.
as far as the GPS goes, its a little on the back burner. My CFI pushing hard for the 430w or 530w, I am not that convinced on spending that amount of coin on such an old product. It seems to be nearly a wash just to buy a current GPS offering and an older Nav radio.
as far as the GPS goes, its a little on the back burner. My CFI pushing hard for the 430w or 530w, I am not that convinced on spending that amount of coin on such an old product. It seems to be nearly a wash just to buy a current GPS offering and an older Nav radio.
GNX 375 get both in one box. As I posted in another thread we did the upgrade back in July in order to get exactly what you are looking for. IFR GPS and a new transponder with ADSB in/out. IMHO it is a more capable and user friendly GPS than the 430/530. Obviously no com but if your radios are working well then keep them for now.
unsafervguy
En-Route
My guess is hes pushing for a 430/530 because he know it. As i have said 1k times, it makes no sense to do a 430/530 as a new install. its been out of production for 8 years, is 20 year old technology and im guessing most of the stuff inside is not available anymore. its reaching EOL rapidly. all the signs are there garmin offered good upgrade pricing to owners, they have raised the repair prices, and have been buying them back. next is sorry charley its not repairable anymore. spend a few bucks more and buy a in production unit.
Bacho
Pre-takeoff checklist
Maybe I need a new thread. Still considering a new GPS/Nav radio. Pretty much torn between a used gtn 650 or a 175/used SL30. Kinda leaning towards the 175/sl30. A little cheaper and gets some redundancy. Is there a reason I should not go that route?
2 reasons off the cuff: panel space and screen size.
Jesse Saint
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The 355 is GPSand Com, but no Nav radio. The only reason not to do the 175/SL30 route is two separate CDI’s.
Chip Sylverne
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Quit with the negative waves, man.
Well, that and you have to punch in your own freqs. The 175 and SL30 don't talk.
JohnAJohnson
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Such a shame the FAA couldn't just say that if a position source is certified with any OUT device, it is certified to use with all OUT devices. Then it would just be a matter of ensuring the GPS sentence complies with the standard. This would be simple, practical, and economical.
I understand this is a pretty old post but it is (almost) the same dilemma I'm currently facing and hopefully someone (Jesse?) has been here before and can help.
I installed a GTX335 ADS-B OUT transponder few years ago under the watchful eye of my AP/IA. GTX335 w/GPS has its own GA35 antenna and GAE12 encoder. The 335 Promo Kit was among the first of Garmin's products released to the certified market for installation outside their dealer network; and not everyone at Garmin was aware of the new program. As a result, back then anyway, getting through to Garmin tech support as a certified owner/installer proved difficult when the "big-box" Garmin Dealer who sold the unit couldn't provide the needed help. We eventually got the issues sorted out and the 335 has been working great.
I've now just pulled the trigger and will soon be installing a Garmin GNC355/GI106B/GA35 Combo Kit which will replace one of my old King Nav/Coms and an old STAR-5000 (vfr) GPS. I've been immersed in the relevant Garmin manuals for the last few days planning the installation and my first question is on antenna options.
First, since the combo kit includes another GA35 antenna, and I have a good spot to mount it where the old gps antenna is now, is there any reason not to leave the existing GTX335 installation just as it now and install the GNC355 as a separate stand alone system with a second GA35 antenna?
And, if the GTX335 and GNC355 systems can be completely independent of each other, must the GNC355 have its own GAE12 encoder for IFR approaches and such?
Second, if there is a good reason for the GNC355 & GTX335 to share one antenna and gps position data, I presume the preferred method would be to connect the antenna to the GNC355 and send the GPS Position Source to the GTX335 via RS-232 as shown in the GNC355 STC & TSO installation manuals. Is this correct? And is this indeed a better solution than sharing one antenna and position source the other way around?
And if the better idea is to reroute the existing GTX335 antenna to the GNC355 and share its position source with the GTX335, must I also, or should I also, relocate the existing GAE12 encoder from the backshell of the GTX335 to the backshell of the GNC355? Or is the RS-232 connection truly bidirectional so that the GTX335's encoder data can be transmitted to the GNC355 and the GNC355 can send the position data to the GTX335?
Any help, advice, or suggestions appreciated! ZT
NordicDave
En-Route
The GNX-375 is the no-brained solution. ADSB In/Out and WAAS GPS. @Bacho, Brilliant solution made for exactly your situation.
Plus Bluetooth interface for iPad EFB’s life ForeFlight or Garmin Pilot.
I agreed wholeheartedly with those who suggested a 375 as the obvious choice to the OP last year but how would that apply to me NordicDave? If you were indeed referring to "my situation?" Did you read my post? Yeah! I know it was a bit long but I try hard not to waste many words.
Just to recap, I've already recently installed a very nice GTX335 ADS-B OUT transponder that I'm quite happy with. I get my traffic and weather on an ipad with Stratus and FF.
My plan is to replace an existing legacy King NAV/COM with a new generation GPS/COM ...and also get rid of an old un-updatable gps.
Any help with my questions would be appreciated. ZT
Jesse Saint
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There is no reason you can’t just install another gps antenna, but that adds time and cost, and it adds another antenna on the top of your plane. If it was me I would connect the GA35 to the 355 and send position data to the 335. The 3d5 can send pressure altitude to the 355, but I don’t think the WAAS Gps needs pressure altitude. The old non-waas units did, but the waas units don’t, iirc. The manual should show the preferred wiring. I don’t think the GAE12 will mount to the 355. It will to the 375, not the 355 (again, iirc).
on a side note, if the king Nav/com has a glideslope indicator, you can probably hook hat indicator to the 355 and save the cost of the GI106.
on a side note, if the king Nav/com has a glideslope indicator, you can probably hook hat indicator to the 355 and save the cost of the GI106.
bnt83
Final Approach
I tried installing GTX-345 with internal GPS receiver without it being attached to a GPS and it constantly flashed "service soon" IDK if you would have the same experience, at that time Garmin tech support said there was no way to disable that even though it was being provided position via a GTN.
I wouldn't worry about the uncorrected baro to the 355. If you get a Garmin G5 later I think that wold get it corrected baro.
I wouldn't worry about the uncorrected baro to the 355. If you get a Garmin G5 later I think that wold get it corrected baro.
jrcox19
Pre-takeoff checklist
Unfortunately they did have a reason for that choice. I've worked with a number of "approved" GPS and "approved" transponder solutions that, when integrated together, did NOT meet the timing/latency requirements.
Technically you can do any approved GPS+transponder, but if somebody hasn't already done the analysis/testing, you're on the hook to qualify it yourself. And there's no guarantees it'll pass
MuseChaser
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MuseChaser
Jesse, thanks for offering your expertise so frequently. A question that may have already been answered but if so, I missed it..
PA28-140, currently installed Narco 12D+ nav/com, CDI (not sure of model), Stratus ESG with GPS antenna, Narco AR850 altitude encoder, older Collins amr350 audio panel.
Like previous poster(s), I'm considering installing a Garmin gps175. Would I be able to/need to use my existing CDI with it? Can that CDI be switched between the existing 12D+ and the prospective 175 if so? Can the existing GPS antenna be shared between the Stratus ESG and the 175? I contacted Appereo months ago inquiring about the possibility of using a 175 as the gps source for the ESG and was told that although that was possible on the ES, there was no field-updateable way to "roll back" an ESG to an ES via firmware or repinning to allow the ESG to accept external gps data. Too bad.. I'd like to avoid installing a second redundant gps antenna.
Thoughts?
NordicDave
En-Route
I wasn't responding to you, but also did not see this thread was a reactivated zombie.
In your case, I'd pull the GTX-335 and sell it as they fetch a premium. Once you fly with ADS-B In from a panel mounted source you'll never go back. Personal preference, I like seeing traffic & weather on ForeFlight and the panel in case something happens to the iPad.
Having flown for a while with Stratus and no longer having to deal with another dongle and it's power source was great to dispatch with.
Good luck on your next steps.
Thanks for your reply Jesse!
RE: Option 1 and adding the "time and cost of another antenna"... I'm not a fat wallet guy Jesse and the only way any of this works for me is that I can install the 355 myself as per the STC under the supervision of my AP/IA. And being retired, I do have plenty of time. I also get a new GA35 antenna with the combo kit and I already have a second gps antenna mounted on top from the old GPS which will either stay in place because it isn't worth taking off or be replaced with the second GA35 for the GNC355.
RE: The GAE12 Encoder. The GAE12 is mentioned twice in the GNC355 STC Install manual. The first instance is in
4.1.2 Backshell Assembly for D-Sub Connectors
Where step 4 states...
"4. Install the configuration module or GAE 12 wires into the connector."
The second instance is in...
A.1.3 Configuration Module
In table A-6,; where it sets forth the pin assignments for the
GNC 355( ) Config/GAE Module Pins
But nowhere else is GAE12 mentioned or any explanation of what it is needed for or required. What I'm wondering is, if an IFR installation of a GNC355 does not include the GAE12 or get uncorrected pressure altitude from some where else, what altitude does the 355 use for IFR LPV approaches?
The 355 install manual does show the GNC355 & GTX335 RS-232 connections but no info is given on which box is sending or receiving the GPS Position Info or any mention of the RS-232 connection sending GAE12 data one way or the other. I've heard that trying to read Garmin install manuals is like trying to take a sip from a firehose, and at this point, I couldn't agree more.
As for the King ILS CDI... I presently have a pair of 175B/170Bs one with ILS (KI-214) and the other with LOC only (KI-208). I'll be removing the 170B and Ki-208 but keeping the 175B and Ki-214 for now. My plan is to leave the 175B/214 combo in place as a stand alone VHF IFR capable backup and (for) now wire up the GI-106B to the GNC355 only. IE. NO STACO SOURCE SELECT SWITCH, RELAYS, or external ANNUNCIATORS required.
Down the road, if I can find my way into a GNC (255?) VHF NAV/COM I'll pull the 175B/214 and wire the new Garmin NAV/COM to the 106B too.
So in light of the additional info above, would you suggest anything different?
I do appreciate your help! ZT
Thanks for your reply bnt83!
ZT
Yeah! I can see why a SEL flashing could be disturbing! Do you expect this issue to be resolved?
My question here is the same one I asked Jesse above... What altitude will the GNC355 for IFR approaches if there is no pressure altitude available to the GNC355?
ZT