GTX345: Review (Install + First Impressions)

Sinistar

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Brad
TLDR Version: Spendy little box, especially when old meets new. Very easy to use, built in ADSB-in is very nice, I like the automated flight timers and "leaving altitude" feature.

Scheduling:
This past winter we decided to go for a GTX345, called around for quotes, picked a shop and pre-bought the unit. Our install was scheduled for the week after July 4th. The week before our scheduled install the shop manager called us and said still on schedule so dropped it of the Sunday afternoon before.

The Install:
Due to the July 4th holiday they didn't start until Tuesday. When I called on Friday he said it was all installed and they were testing. I'm thinking...sweet...no problems. Then I get a email on Sunday (who gets emails from avionics shops on Sunday :eek:). The shop manager was really backlogged and explained that it is failing the COM radio interference test procedure. As I understand it, they transmit on 15 different frequencies on each COM device. We have a pair of KX155's.

Problem # 1 was in the KX155 with ILS/GS. They installed some filters and still no joy. The installer then took it (KX155) apart and cleaned up contacts and I think the culprit was in whatever grounds it to the case, perhaps where the tray is locks engage???

Problem # 2 was the second KX155 was getting into our old ELT circuit and then re-transmitting crud which drops the GPS signal enough to fail. They installed some filters and still no joy. They temporarily moved the ELT antennae back about 2.5ft and it solved the problem. I really liked our previous ELT location, halfway between the back window and dorsal part of the rudder. Now its a few inches behind the dorsal and off to one side. Plus a decent, but kind of big plug in the old hole.

Some Additional Work / Comments:
I also had them pull the DME since it was no longer functional. Fortunately he was able to place the top mount GPS antennae where an old antennae post was...so no new holes above the cockpit. Since there were wires there already he was able to follow that same route avoid pulling the entire headliner :) Instead he pulled a side panel and post panel going up by the door. I had also left him a headset to mini plug cable that I use for my gopro audio. He routed it up the same post and now I have a dedicate cable right up to the cabin dome light area where we occasionally mount the gopro. No more dangling GOPRO audio cable back down to a headset station :) @Radar Contact would dig this. Test flew it yesterday and worked great.

Labor/Cost
All in it was 30hrs of labor. If I understand right about 5...6 hours of that labor was to figure and resolve both those issues. I am not sure of the DME tray and wire removal hours but I am sure it had to be at least one or two hours. So, maybe if someone had an older panel but no noise issues you might be looking at about 20hrs of labor, maybe a bit less. It also requires a new Pitot Static/Encoder test. Using $90/hr that is still pushing $2K to install. Throw in a new encoder and the base unit price and its easily $7300 or so before taxes and any problems. Hopefully others have less issues. He said that our case happens around 5% of the installs.

W&B
All said and done we brought the Skylane home 1.5lbs lighter then when we dropped it off.

The Shop
I would use them again. Will probably do the new GNC 355a next year. The manager is very busy so a bit hard to get ahold of. I am sure with all the other ADSB installs, airventure being around the corner and the recent Garmin announcements he was swamped. However the installer met me and explained everything, offered some advice, etc. He also unlocked a few mysteries. He said our intercom is wired wrong (something about incorrect shielding). He said why mess with it if it works but told us what will happen if there is an issue. He also explained the mystery of our tailbeacon being on the radio master. He said from the factory there was a relay behind the panel and the tailbeacon is on this relay. Its to protect the flasher because the radio master is turned on after the startup EMF spike.

Test Flight Issues:
Actually the unit is pretty simple but with all that labor my wife and I made a extensive list and there was lots to check. Everything from transmitting on all radios, both stations, all VOR's, ILS/GS, ELT, Dome lights, altimeter, etc. All headset stations, etc. So far I have noticed the following :

#1: During initial climb out I noticed the GPS location (via Garmin Pilot) seemed stuck for about 10 seconds. It did not show a loss of GPS but like it was hunting for which direction I was flying. I do not recall transmitting anything at that time but maybe I did. So now I am really watching for this. On my second flight there was lots of radio tx as I went to a pancake breakfast and we did a in-air meetup (122.75) for pictures. But no GPS loss.

#2: On the second flight my Garmin Pilot crashed (Android Version) but it had done this on a previous flight as well using the GDL39-3D. I will test next time with our iPad Mini 4 and Galaxy tablet running at the same time and see what happens.

#3: The last issue was my own doing - that I went into the installer menu and lowered the aural alert volume from 60 to 40. It sounded too loud down on the ground. But in the air I could hardly hear it...so its going back to 60.

The Good Stuff
It comes up quick and auto pairs with the Android and iPad tablets quickly. I locks onto more ADSB GBT's than my GDL39 did thanks to now getting the signal down at the belly vs up on the dash. Entering a ATC xpdr code and going back to 1200 is way easier. I like the flight timers and altitude alerts. Now I know that IDENT lasts 18 seconds (had no clue on the old box). Every flight now shows up on FlightAware, even without Flight Following. My wife likes this in case there a "he's running late" moment. Obviously not very anonymous if you're that type.

What Would I Change
The price (obvious).

I didn't realize there is a OAT input so I would have installed that (if not too $$$$). That would have enabled Density Altitude and OAT being displayed.

Next, I wish the unit could set altitude deviation alerts less than 200ft. I'd like to set it at 100ft for a while to remind me how bad I hand fly altitude :)

I wish there was a way to have it display the altimeter value instead of the pressure altitude (not a big deal but seems more useful).

Rebate Dilema
So I was trying to be strategic and file for the rebate around 90 days before the install. Right about the time I was going to reserve they were all used up. So this creates a dilemma. My understanding is once you fly with the xpdr on you are now exempt from the rebate. So its either leave it off and check every Wednesday. Or blow off the rebate and test fly it to be sure it all works. I did the later. I might still try for a rebate but doubt it will work.
 
You are exempt from the rebate if you have flown and have not reserved the rebate. The idea is to encourage those who have not yet decided to purchase. If you have already purchased, then there is no need to motivate your purchase. When the program still had rebates to reserve, you had to reserve and schedule an installation during the process.
 
One of the airplanes I frequent just had the GTX345 installed, to accompany an already installed GTN650. Paired up to my iPad and Foreflight, this thing is amazing. I've barely skimmed the top of what it is capable of. They also updated the 650 software, so it has a new few features as well. Its like a whole new airplane, except I still know how to land it.
 
like mine
not feeling the joy the price seems to promise
anyone know how many bt devices it ought to feed at one time?
 
TLDR Version: Spendy little box, especially when old meets new. Very easy to use, built in ADSB-in is very nice, I like the automated flight timers and "leaving altitude" feature.

I've had two GTX345 units for the past couple of years now...what is the "Leaving Altitude feature"? I was unaware it did more than I already have it doing! lol
 
All I know is that I use the ADS-B (in) data from the GTX-345 displayed on my GTN-650 every flight. The weather data has been great, textual metars when out of VHF radio range is awesome too.


I can sit at a runway hold-short line and watch landing & departing traffic out the window and the ADS-B and can't see any lag.
 
Now the fun part. Trivia. Why does an Ident take 18 seconds? :)
Something to do with the rotational time of the radar...like they want at least 'N' successive sweeps with responses - maybe 18seconds is for the slowest radar rotation rates out there. After that I am outta ideas and curious!
 
All I know is that I use the ADS-B (in) data from the GTX-345 displayed on my GTN-650 every flight. The weather data has been great, textual metars when out of VHF radio range is awesome too.


I can sit at a runway hold-short line and watch landing & departing traffic out the window and the ADS-B and can't see any lag.
Yeah, ours updates very quickly. If you think about it the boxes liked the GTX345 are receiving 1090 data directly so the delay should be the rate at which those are transmitted which is 1 second. It (traffic) is such little data that the Bluetooth bandwidth restrictions shouldn't be visible. And if you are at an airport with a ADSB ground based transmitter (GBT) I am sure it sending traffic all the time as there is probably almost always 2 aircraft near each other out in the pattern, etc.
 
I've had two GTX345 units for the past couple of years now...what is the "Leaving Altitude feature"? I was unaware it did more than I already have it doing! lol
The GTX345 has at least 3 aural alerts that I am aware of. You can enter the setup mode and it will play each one. You can also adjust the volume in there somewhere. My installer said it is hooked right into the intercom system and not placed on any of the aux audio panel inputs. So its always there (if wired) but the alerts maybe be disabled or you have not used one of the features or just never heard one (low volume). They are:

1. Traffic - I haven't heard this one yet, I think you need to be somewhat close and maybe only it computes a close intersection
2. Countdown timer expires - but you have to enter and start a countdown timer to hear it
3. Leaving Altitude - like the timer you need to go to that screen and turn it on which uses the pressure altitude you are at. The setup menus let you set the deviation amount (can be 200ft or more).

....I would suggest entering the setup mode on the ground and with plane off and just the intercom and GTX345 on, go to the page that lets you play each of the 3 alerts and hear the volume. If you don't get anything after that then it may not be wired or it was wired to a aux input on your audio panel.
 
like mine
not feeling the joy the price seems to promise
anyone know how many bt devices it ought to feed at one time?
I feel like if I have a navigator (530/650/750/175/355/375) it will be of more value since all the ADSB in stuff can be displayed on their screens. Otherwise other than being compliant the pilot sees more of the value via the ADSB in and tablet which you can also get with any portable ADSB in device. But I do like having it built in. Once less thing to fidget with, one less thing up on the dash.

I know you can hook up 2 Bluetooth devices because I just did it on Sunday. I had one displaying the sectional and the other showing synthetic vision. One was a Android and one was iPad mini 4. If I can find someone with another tablet I can try a 3rd.

I know the GDL39 supposedly supports 4 so I would think it would support 4.
 
Sweet writeup, thanks for the comprehensive Skybeacon endorsement.
Actually I am glad you see it that way. I do like the GTX345 and I think it will fill in a nice spot with our Garmin Navigator next year. But if you aren't going a route like that the Skybeacon (and LED light) are probably an excellent option. It also means some type of ADSB in device (if you want it) but I am thinking the market will start to drop on used GDL39 and the earliest Stratus portables.

I am in the camp of wanting to be seen. I really like the idea of the GTX345 cranking out 200watts on 1090 so that was our other reason.

Its too bad the sky beacon people can't make another gadget for ADSB in that is mounted down on the belly and also provides second feature like a light to piggy back off of. Or build it into their beacon (if it is not already).
 
The GTX345 has at least 3 aural alerts that I am aware of. You can enter the setup mode and it will play each one. You can also adjust the volume in there somewhere. My installer said it is hooked right into the intercom system and not placed on any of the aux audio panel inputs. So its always there (if wired) but the alerts maybe be disabled or you have not used one of the features or just never heard one (low volume). They are:

1. Traffic - I haven't heard this one yet, I think you need to be somewhat close and maybe only it computes a close intersection
2. Countdown timer expires - but you have to enter and start a countdown timer to hear it
3. Leaving Altitude - like the timer you need to go to that screen and turn it on which uses the pressure altitude you are at. The setup menus let you set the deviation amount (can be 200ft or more).

....I would suggest entering the setup mode on the ground and with plane off and just the intercom and GTX345 on, go to the page that lets you play each of the 3 alerts and hear the volume. If you don't get anything after that then it may not be wired or it was wired to a aux input on your audio panel.

Traffic comes through my GTN650 (hooked up to the GTX345), so that explains why I've not heard that. The countdown timer I think I knew about, but just never use. The leaving altitude is intriguing though depending on how difficult it is to set an altitude. Rarely do I even physically touch the 345 since I set it through the 650, so I guess I've just never really thought about it being capable of more. Interesting stuff though!
 
Setting the altitude departure alert is fairly simple since you do not enter the actual altitude. Instead you FUNC to the option. I think you press CURS to select it and press one more key to activate it. It then uses the altitude you are flying at. I think it actually uses the Pressure Altitude you are flying at since xpdrs do not have the local field elevation offset correction. I guess I found it easy to use. I would think your 650 might already do this altitude thing anyway.
 
Something to do with the rotational time of the radar...like they want at least 'N' successive sweeps with responses - maybe 18seconds is for the slowest radar rotation rates out there. After that I am outta ideas and curious!

You got it. Enough time for the old long range radars to come around and the secondary antenna on top of the primary to see it. :)
 
I feel like if I have a navigator (530/650/750/175/355/375) it will be of more value since all the ADSB in stuff can be displayed on their screens. Otherwise other than being compliant the pilot sees more of the value via the ADSB in and tablet which you can also get with any portable ADSB in device. But I do like having it built in. Once less thing to fidget with, one less thing up on the dash.

I know you can hook up 2 Bluetooth devices because I just did it on Sunday. I had one displaying the sectional and the other showing synthetic vision. One was a Android and one was iPad mini 4. If I can find someone with another tablet I can try a 3rd.

I know the GDL39 supposedly supports 4 so I would think it would support 4.

I’ve found on the smaller screen navigators that pushing traffic to an iPad makes life a whole lot easier. Including Garmin Pilot’s dedicated traffic screen on the iPad where you don’t HAVE to have the moving map displayed.

Sitting in the right seat as a CFI I like that traffic screen if I can see a map elsewhere. Traffic screen sits in my lap for quick glances in insane traffic airspace.

YMMV. :)
 
I know you can hook up 2 Bluetooth devices because I just did it on Sunday. I had one displaying the sectional and the other showing synthetic vision. One was a Android and one was iPad mini 4. If I can find someone with another tablet I can try a 3rd.

I know the GDL39 supposedly supports 4 so I would think it would support 4.

Yeah there’s a published limit on our Flightstream 510 but it’s high. Everyone on board could have a map up AFAICT. Or quite a few anyway.

Should be able to find it for the newbie box. Hah. It’s out there somewhere in Garmin’s docs! :)
 
Traffic comes through my GTN650 (hooked up to the GTX345), so that explains why I've not heard that. The countdown timer I think I knew about, but just never use. The leaving altitude is intriguing though depending on how difficult it is to set an altitude. Rarely do I even physically touch the 345 since I set it through the 650, so I guess I've just never really thought about it being capable of more. Interesting stuff though!

In that setup I’ve also never heard an altitude alert if set on the 345. But maybe there’s an audio line that needs to be run from it to the always active intercom input.

Traffic alerts, definitely ... coming from the 650.
 
Rebate Dilema
So I was trying to be strategic and file for the rebate around 90 days before the install. Right about the time I was going to reserve they were all used up. So this creates a dilemma. My understanding is once you fly with the xpdr on you are now exempt from the rebate. So its either leave it off and check every Wednesday. Or blow off the rebate and test fly it to be sure it all works. I did the later. I might still try for a rebate but doubt it will work.

Not trying to flaunt the rules, just pointing out that due to 91.225(f) it’s not a dilemma...
 
Not trying to flaunt the rules, just pointing out that due to 91.225(f) it’s not a dilemma...
The dilemma isn't that the rebate is no longer valid because I flew. The dilemma is that I could have just turned it off for the next 'N' weeks and kept trying for a Wednesday lunchtime release of a unused rebate. But after all that stuff was tweaked I wanted to test fly it and get it back in the shop ASAP, especially if there were squawks due to their work (which turned out to be none).

Lets call it a hassle if that works better.

I probably wouldn't have even mentioned it but I bet there has to be another few hundred (ADSB) installs queued up across the country trying to get this done by 12/31/2019. They will receive the same advice from their installer - fly it once and you are no longer eligible...but leave it off until you get lucky on a Wednesday and its $500 time. There may be even more installs now with the 375 unit as people might have decided to do nothing but the 375 sweetened the pot enough to go for it. So in a way the 375 probably locked up the final rebates.
 
In that setup I’ve also never heard an altitude alert if set on the 345. But maybe there’s an audio line that needs to be run from it to the always active intercom input.

Traffic alerts, definitely ... coming from the 650.
I was hearing it last night but it was so quiet. That was with the GTX345 volume set at 60. I'm gonna bump it up to 80 for the next flight. Remember, you won't hear an alert until you've pressed a few buttons on the GTX345 to actually turn it on at the altitude you are currently fly at.

I have an example from last night (although too quiet). Almost the entire flight was under the Bravo. I set it up when at 3700msl prior to going under the 4000msl layer. The only time it went off was when we descended to fly around a lake. So it was just one more tool to help me not bust the Bravo. There's a lot of MSP arrivals/departures in this section of the Bravo with departures just 1300ft above us on a few occasions! So I am watching the altimeter like crazy anyway.
 
The dilemma isn't that the rebate is no longer valid because I flew. The dilemma is that I could have just turned it off for the next 'N' weeks and kept trying for a Wednesday lunchtime release of a unused rebate.

Understood, my point was that 91.225(f) doesn’t allow you to turn it off, once installed it must be on at all times. I think a bit of overreach by the FAA, especially because there is airspace that doesn’t require ADSB, let alone a transponder, but it’s a rule...
 
Understood, my point was that 91.225(f) doesn’t allow you to turn it off, once installed it must be on at all times. I think a bit of overreach by the FAA, especially because there is airspace that doesn’t require ADSB, let alone a transponder, but it’s a rule...
Okay, yes my misunderstanding then. I thought it could be turned off when not in the ADSB required airspaces?

EDIT: Yes, the 14.CFR.91.225(f) has no exemptions or exclusions. If a ADSB out device is installed it must be on. I guess to fly the plane with it off would be a violation.

Thanks @idahoflier for the clarification!!!!
 
I wish there was a way to have it display the altimeter value instead of the pressure altitude (not a big deal but seems more useful).

What do you mean by "display the altimeter value"? And where would it get that from?

anyone know how many bt devices it ought to feed at one time?

Two. (Ref: Manual page 6-1.)

That is, two active devices. You can pair up to 13 devices and they'll auto-connect again, if you pair a 14th device it forgets the 13th device. The first 12 remain forever until you delete them.
 
Thanks for the reference on max connected devices. I was thinking the GDL39 could do up to 4 but that's not relevant here.

Regarding the "altimeter" I should have said the altitude that corresponds to the altimeter. The transponder is clearly being fed in the static pressure and thus pressure altitude via a encodoer. If it could also receive the Kollsman window offset then it could display the altimeter value. Not needed but it's weird to see it always displaying pressure altitude. Not a number we typically use down low in the plane below 18,000.
 
That is, two active devices. You can pair up to 13 devices and they'll auto-connect again, if you pair a 14th device it forgets the 13th device. The first 12 remain forever until you delete them.

One thing I have found with my ipad & my iphone is that it often wont connect to BT devices.
I have to click each previous connection and find the ‘Forget this device’ for each, and only then will it connect to the new device.

iphone & ipad 12.3.1
 
Not needed but it's weird to see it always displaying pressure altitude.
I don't think I've ever flown with a transponder that displayed anything other than pressure altitude. I think it would be weird to me if I ever see one that displayed true/indicated altitude.
 
I don't think I've ever flown with a transponder that displayed anything other than pressure altitude. I think it would be weird to me if I ever see one that displayed true/indicated altitude.
If it didn't have the altitude alert I don't think it would be a big deal. Yes, setting it to the corresponding pressure altitude works just fine. But would be more in "synch" if it matched the altimeter. There is some irony...I have never flown in a plane until now that had a transponder that actually displayed anything other than a red led blinking with ATC radar sweeps it. Thus I just expected it to show adjusted altitude not density altitude. You learn something every day.
 
If it didn't have the altitude alert I don't think it would be a big deal. Yes, setting it to the corresponding pressure altitude works just fine. But would be more in "synch" if it matched the altimeter. There is some irony...I have never flown in a plane until now that had a transponder that actually displayed anything other than a red led blinking with ATC radar sweeps it. Thus I just expected it to show adjusted altitude not density altitude. You learn something every day.

If it’s not going to run you into a mountain you can just tweak the altimeter to match.

Hahahaha. Which error do you want? :)

Can ask your static system check person to show you the chart of how far off each one is during the test over the full range of altitudes.

Most do that before signing off the aircraft for another couple of years. Some give you the paperwork, some don’t.

Our guy does. Has all the test stuff hooked to his laptop for the static and the transponder and a mobile printer, and he just hits print and gives us all the gooey yummy test details we want — or didn’t know we wanted until we used him. Ha.
 
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