Avidyne 440 vs GN355/175/375

cielbleu

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cielbleu
I am buying a certified aircraft with the following avionic :
Avidyne 440
Garmin GMA340
Garmin GNC250
Stratus Appareo xpdr
JPI 900

I have never used a Avidyne before, so I downloaded the ipad simulator to test it out.
So far, I really find a Garmin GN355/175/375 more user friendly. But everybody swears the Avidyne is superior.
I am looking for opinions from people that have actually used either of them, or have selected one or the other for their airplane.
I am planning to add a G3x or Dynon Skyview together with an autopilot. The Dynon autopilot will only be available this year or god only knows when. The Garmin is already available.

I am looking at a few options :
1) just add the Dynon Skyview and wait for the autopilot to arrive. Keep the Avidyne (easier option)
2) add a G3X but not sure how this will go with the Avidyne, and minor detail but, I guess I will need 2 subscription to update. (correct me if I am wrong)
3) replace the Avidyne with a GN355 and install a G3X with Garmin autopilot.

I also need some input as far as cost is concerned. If I replace the Avidyne, it looks like I could sell it for around 9K and buy a GN355 for around 6.5K, but what about install ? Will it be easy since the wiring might already be there, although it might require a new antenna ? In other words, would I save money doing that ?

Thanks for your input
 
So far, I really find a Garmin GN355/175/375 more user friendly. But everybody swears the Avidyne is superior.
The 440 is GPS/NAV/COM while all the other 2" units you mentioned lack VOR/LOC/GS capability. I'd keep the 440 for that reason alone.
 
Learn the Avidyne. It’s already installed. It will work fine with either the Dynon or the G3X. What model airplane are you talking about?
 
The one you know how to use is superior. Really.

They are all excellent units with close to 99% of the difference being flow rather than function.

I'd keep and learn how to use that 440 competently.
 
The one you know how to use is superior. Really.

They are all excellent units with close to 99% of the difference being flow rather than function.

I'd keep and learn how to use that 440 competently.
The one that's paid for and installed is superior
 
Since it’s already there and working, learn it. You will have ample opportunity to spend $$.

One note, if you decide on Garmin AP, VNAV coupling is not an option without Garmin nav, unless they have changed it very recently. If you go with G3X that db and approach plate will cost extra. Coupled with Garmin nav, a pilot pack will suffice. Not sure how it works with Dynon (charts and stuff)
 
My recommendation is keep the avidyne for now and take care of the rest first (and that can be a big topic of discussion as well). By the time you're done, you might decide to keep the 440.

Fortunately for you, the plane already has a JPI 900.
 
I am buying a certified aircraft with the following avionic :
Avidyne 440
Garmin GMA340
Garmin GNC250
Stratus Appareo xpdr
JPI 900

I have never used a Avidyne before, so I downloaded the ipad simulator to test it out.
So far, I really find a Garmin GN355/175/375 more user friendly. But everybody swears the Avidyne is superior.
I am looking for opinions from people that have actually used either of them, or have selected one or the other for their airplane.
I am planning to add a G3x or Dynon Skyview together with an autopilot. The Dynon autopilot will only be available this year or god only knows when. The Garmin is already available.

I am looking at a few options :
1) just add the Dynon Skyview and wait for the autopilot to arrive. Keep the Avidyne (easier option)
2) add a G3X but not sure how this will go with the Avidyne, and minor detail but, I guess I will need 2 subscription to update. (correct me if I am wrong)
3) replace the Avidyne with a GN355 and install a G3X with Garmin autopilot.

I also need some input as far as cost is concerned. If I replace the Avidyne, it looks like I could sell it for around 9K and buy a GN355 for around 6.5K, but what about install ? Will it be easy since the wiring might already be there, although it might require a new antenna ? In other words, would I save money doing that ?

Thanks for your input
The GTN and IFD are comparable in every way the matters. The GTN has a few more pixels; the IFD has a few more knobs; etc — all trivial stuff that only hardcore fanboys/girls try to inflate into more than just a matter of personal taste, or of what else you want to integrate with (or, with the IFD, if you want a slide-in replacement for an old GNS).

When you start talking about the Garmin 175, etc, however, you're into a different product category. Both the GTN and IFD are (in the most-popular configs) GPS/NAV/COMM combos. The new, less-expensive Garmins are a standalone GPS, a GPS/ADS-B transponder combo (very cool), or a GPS/COMM combo.

I personally also prefer the GTN to the IFD (as a matter of taste), but if I bought a plane with the IFD already installed, I'd just keep it.
 
One note, if you decide on Garmin AP, VNAV coupling is not an option without Garmin nav, unless they have changed it very recently.
I believe the 2" navigators that the OP cited (175/355/375) don't supports VNAV, only VCALC. Stepping up to a GTN changes the value proposition by quite a bit.
 
I believe the 2" navigators that the OP cited (175/355/375) don't supports VNAV, only VCALC. Stepping up to a GTN changes the value proposition by quite a bit.
Interesting point that I’ll have to verify. However, the 175, etc... are approved for LPV approaches, don’t you have to have VNAV with it ?
 
Interesting point that I’ll have to verify. However, the 175, etc... are approved for LPV approaches, don’t you have to have VNAV with it ?
No. You need WAAS for both, but LPV glidepath and VNAV are different functions. VNAV wasn't available in the GNS series but LPV was.
 
No. You need WAAS for both, but LPV glidepath and VNAV are different functions. VNAV wasn't available in the GNS series but LPV was.
I see. So you can fly a LPV coupled approach but not a LNAV/VNAV. (Glide path)
So either LPV or LNAV approach.
 
I see. So you can fly a LPV coupled approach but not a LNAV/VNAV. (Glide path)
So either LPV or LNAV approach.

The VNAV term is a bit overloaded here… the 2” navigators will do approach VNAV just fine. They do not have the descent VNAV where you can set crossing restrictions for fixes and get advisory descent info (or with a GFC autopilot couple for descent VNAV)

ABD1878A-A30C-4661-AF88-785E675BBAAB.jpeg
 
I see. So you can fly a LPV coupled approach but not a LNAV/VNAV. (Glide path)
So either LPV or LNAV approach.
To put it simply, the GPS 175 can fly any RNAV approach that the GTN or IFD can. What it can't fly is an ILS, LOC, or VOR approach. I imagine most budget-conscioius owners who squeeze a GPS 175 into their panel to add RNAV capability will keep at least one of their old navcom radios (e.g. a KX-155 or even a KX-170B).
 
One of the best pieces of advice I got when I bought my airplane was this: Fly the plane for a year before planning any modifications or upgrades. The rationale is simply that it takes a certain amount of flying the new (to you) plane before you really know what you like and what might help you in the future. I see nothing wrong with the avionics in the plane you describe, @cielbleu

Congrats on the new plane!

-Martin
 
I see. So you can fly a LPV coupled approach but not a LNAV/VNAV. (Glide path)
So either LPV or LNAV approach.
Unfortunately, VNAV is used to mean two completely different things.

In LNAV/VNAV, it's referring to a type of approach originally meant for airlines with barometric VNAV systems. In most cases, WAAS-based GPS units are authorized to use them. The VNAV we are talking about here though, is an enroute and terminal vertical navigation system designed to calculate TOD and BODs to meet crossing restrictions and approach stepdowns prior to the FAF. LNAV/VNAV and LPV glide paths activate then the FAF is the active waypoint).

It's different from VCalc (which I think the 175 has) in that, in addition to calculating a descent rate, it also produces a vertical path which it can put on your PFD as a "V" glidepath and feed an autopilot. Garmin also uses the tern "VNV," probably a good idea to avoid confusion.

If you want to see VNV in action, I did a video for my flying club demonstrating its use in a G1000.
 
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OP blame me for the confusion, when i made my comment, i had GTN series in mind
 
Since the avidyne is so beloved, I suppose OP could offer to swap someone for their 430W and a few $$$ no? I'd probably consider that -- I actually like the Avidyne units (no time with a 440, but I've liked the 540 and 550 I've flown with) but they're a tiny fish in a big garmin ocean, and I'd probably want to be in the mainstream myself.
 
I am retired from a career that consisted mostly in automation system development. The most common objection to any new control and monitoring system is related to the need for a change in habits, routines or mindset. At this point the 440 is not intuitive to you because you are already acclimated to different system. My advice is to adapt to the 440. There are many people who pay money to change to the 440 or 540 so it must be at a minimum adequate, but I expect that it is much more than aequate.

if it were me, changing the panel because I am familiar with something else would never enter my mind.

Just dive in and learn the new system. You won’t regret it.
 
I'm not an IFD fan, but the 440 is a more capable unit than the 355/375/175. I like having at least one all in one in the panel. Keep the 440, unless you're going to spend for a GTN
 
I have a 375 in my Skyhawk. You can load a Vor or ILS approach in the 375 and fly it but it is not approved for those approaches but only as a backup to the Nav/Com. The Vor and ILS approaches will be displayed on the screen.
 
I am retired from a career that consisted mostly in automation system development. The most common objection to any new control and monitoring system is related to the need for a change in habits, routines or mindset. At this point the 440 is not intuitive to you because you are already acclimated to different system. My advice is to adapt to the 440. There are many people who pay money to change to the 440 or 540 so it must be at a minimum adequate, but I expect that it is much more than aequate.

if it were me, changing the panel because I am familiar with something else would never enter my mind.

Just dive in and learn the new system. You won’t regret it.

I am used to learn various system, so it's not the issue. I didn't know either of them and downloaded both trainer and started using them. The Garmin was very easy to use, with easy menu buttons, larger than the avidyne.
I find the map display a lot clearer than the avidyne, but this is just personal.
At this point, if this was an easy swap, I would totally do it because nobody has given me a good reason to stick to the avidyne other than go ahead and learn it.
After some research, (I am not a mechanic or avionic specialist), it seemed that going from a 430 to an avidyne is an easy upgrade, so going from an avidyne to a 355 should also be easy. Anybody could confirm this ? Does it require rewiring the gps antenna ? Looking at the price difference of both units, looks like I could maybe save 2-3K selling the avidyne and buying the 355, money I could spend somewhere else.
 
The fact that the 440 plugs in place of a 430W makes it very marketable. It sounds like a matter of whether or not you feel more comfortable with the 355 to the level that you’re willing to turn loose of that much cash.

Unless there is a serious show stopper feature that the 440 doesn’t possess, I still contend that a little time and you would be comfortable with the unit currently installed in the plane. I’ve seen this scenario numerous times, but if it is worth it to you to have something different, it’s your money and you should by all means buy what you want.

By the way, the 440 literally plugs into the tray from which a 430 is removed. It is literally a five minute change. Going from the 440 to a 350 is not a plug and play change. It will involve the complete reinstallation process by an avionics shop.
 
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The fact that the 440 plugs in place of a 430W makes it very marketable. It sounds like a matter of whether or not you feel more comfortable with the 355 to the level that you’re willing to turn loose of that much cash.

Unless there is a serious show stopper feature that the 440 doesn’t possess, I still contend that a little time and you would be comfortable with the unit currently installed in the plane. I’ve seen this scenario numerous times, but if it is worth it to you to have something different, it’s your money and you should by all means buy what you want.

By the way, the 440 literally plugs into the tray from which a 430 is removed. It is literally a five minute change. Going from the 440 to a 350 is not a plug and play change. It will involve the complete reinstallation process by an avionics shop.

I am still trying to get a dollar amount. I have no idea, so maybe that will be the decision factor.
It’s actually the deciding factor whether to go with a G3X (my understanding is G3X not compatible with the avidyne). If swapping the avidyne for the 355 is too expensive, I’ll go with a dynon instead but will have to wait for the autopilot to become available.
So if I am going to spend 25-30k (just an estimate), wouldn’t I rather go with my number one choice, If I am losing a couple of thousand swapping the gps.
 
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Yes, with the other gear in the equation, not only running up the bill, but also putting compatibility issues in the equation it makes it a different kettle of fish. Again, the 440 is very marketable since it is a plug in replacement for one of the most installed navigators ever sold. If Garmin were to announce discontinuance of support for the 430, the Avidyne 440 would be a bar of gold.
 
I'm not an IFD fan, but the 440 is a more capable unit than the 355/375/175. I like having at least one all in one in the panel. Keep the 440, unless you're going to spend for a GTN
Exactly. To go back a few tech generations, when I bought my plane in 2002 it had a Narco ADF 850 in the panel, and since I was doing IFR training, I was going to be using it all the time. I would have far preferred a Bendix-King Silver Crown ADF (the Narco can be flakey, and the B-K would have matched most of the rest of my avionics stack), but I decided it was more economical to redo my preferences than my panel. :)

Jumping to the present, regardless of what brand GPS you're using, you should be looking 99× at the CDI or HSI when flying IFR for every 1× you look at the GPS.

The GPS differences are mainly a matter of where you tap/twiddle to make flight plan changes or select an approach, so we're talking about (maybe) 5 min/flight that the GPS brand actually matters.
 
I would totally do it because nobody has given me a good reason to stick to the avidyne
That's an interesting approach. When I have two equally capable choices, one of which I already have and the other of which I have to pay thousands to get, I would need a good reason to make the switch.

And yes, A GTN 650 (never mind the pared-down units you are looking at) and an IFD 440 are equally capable. I did a short series of YouTube videos this past year where I compared the GTN and IFD (and the GNS) doing a series of less common but real IFR tasks (they are ones I give my trainees on IPCs). Given an airplane with a current Avidyne IFD installed, I wouldn't even think of changing it out, unless it was to something with a larger screen or more mission-critical capability.
 
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I am used to learn various system, so it's not the issue. I didn't know either of them and downloaded both trainer and started using them. The Garmin was very easy to use, with easy menu buttons, larger than the avidyne.
I find the map display a lot clearer than the avidyne, but this is just personal.
Fully agree. That's one of the things that led me to buy a GTN 650 instead of an IFD 440 in 2017 (the other is that it cost $1,500 less at the time, though that's changed now). Also, while I could just download the GTN trainer anonymously from Garmin, I had to fill in a request with personal information at the time to download Avidyne's (which was kind-of creepy), and then it kept crashing on my laptop anyway. But none of these things would have prevented me from keeping an IFD 440 if it were already in my panel; if someone else spent the almost $20K to buy and install it there for me, why look a gift horse in the mouth?

At this point, if this was an easy swap, I would totally do it because nobody has given me a good reason to stick to the avidyne other than go ahead and learn it.
OK, here are some (from a GTN fan, no less):
  1. It's going to cost you a lot to install a new unit, possibly more than the price of the unit itself (especially if you go with one of the inexpensive Garmins).
  2. Avidyne has a tablet app called the "IFD 100" (iOS only, sadly) that doesn't just connect with the IFD 440 like ForeFlight does, but actually is part of the IFD 440, allowing you to control it completely from the tablet.
  3. The IFD 440 (I think) supports a remote Bluetooth keyboard, so you can put one on your kneeboard and type in waypoints just like the airline pilots do.
  4. IFD supports the "Boeing banana", a little marker on the screen that shows where to start/end your descent (the GTN has that too, but displays it only if you connect a corrected barometric altitude source; the IFD spitballs it based on WAAS altitude, which might be a fair bit off indicated, but is usually close-ish).
  5. The IFD series is more open than the GTN series, and integrates with more third-party stuff — that's a normal marketing strategy for the second-place contender in a market, but it's still nice.
None of those was enough to convince me to buy an IFD 440 instead of a GTN 650 when I was starting from scratch, but if the IFD had already been in my plane, I would have taken advantage of them.
 
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I swapped out my 430W for an IFD440 about a year after buying my plane, huge upgrade IMO. I always had trouble remembering where to find things in all the nested menus in the 430. I actually didn't even consider a GTN 650 because of install costs.

Saying the IFD440 is a 5 min swap from a GNS 430W isn't always true. It depends on the rest of your avionics. In my case, I have a GTX 345, and although it worked "plug and play" some things had to be re-configured in it's settings. And, ADS-b weather would not flow into my IFD 440 until adding another dedicated line. The IFD series receives that differently than the GNS did. I have added more upgrades since then and have had that line added, so now everything is shared as it should be.

I love my IFD, and although the 440 screen may not be as good as the GTN I find I use the IFD100 app for about 80% of my interaction with the IFD. I find the yoke mounted Ipad mini screen to be about the perfect size. A huge advantage to the IFD is built in wifi and bluetooth, no need to buy anything for flight plan transfers. Works with most EFB's, outside of Garmin Pilot.

The only disadvantage for me is you're locked in to Jeppesen. Not as big a deal as it once was as Avidyne has negotiated the price for data bases and charts.

If you ever want to upgrade to a Garmin autopilot I'd certainly stay all Garmin tho.
 
Physical change from 430 to 440 is five minutes. Setup takes longer, but a fraction of the time that a complete physical installation typically costs.
 
A huge advantage to the IFD is built in wifi and bluetooth, no need to buy anything for flight plan transfers.
Quick note: while the GTN series does not have free, built-in wireless, the newer Garmins (175, etc) do.

When I was shopping in mid-2017, the wireless in the IFD was still a software unlock for an extra $1.5K or so, but that changed shortly afterwards.
 
Physical change from 430 to 440 is five minutes. Setup takes longer, but a fraction of the time that a complete physical installation typically costs.
Yes, the IFD definitely has a hold on the niche market for upgrades from old GNS units. Dominating a niche is a good beachhead strategy for a smaller competitor, but years later, I think Avidyne's still struggling to break out and move past it.
 
Yes, the IFD definitely has a hold on the niche market for upgrades from old GNS units. Dominating a niche is a good beachhead strategy for a smaller competitor, but years later, I think Avidyne's still struggling to break out and move past it.
The guys who are in early and develop the biggest market share always have a competitive advantage.
 
I expect that Garmin won’t let that happen. They own the market and protect the market by making so much of the connectivity and compatibility proprietary. They won’t allow any open connectivity or protocols. I saw this in the automation industry as it shook out over a twenty year period. In the beginning there were probably a half dozen viable programmable controller brands, but due to maneuvering and controlling the communication protocols, one of them basically took over the industry with about as close to closed interoperability as any single brand could get. The results was a virtual lock on the market. Garmin is doing the same type thing and already virtually own the market with little alternative for the customers out there.
 
I expect that Garmin won’t let that happen. They own the market and protect the market by making so much of the connectivity and compatibility proprietary. They won’t allow any open connectivity or protocols. I saw this in the automation industry as it shook out over a twenty year period. In the beginning there were probably a half dozen viable programmable controller brands, but due to maneuvering and controlling the communication protocols, one of them basically took over the industry with about as close to closed interoperability as any single brand could get. The results was a virtual lock on the market. Garmin is doing the same type thing and already virtually own the market with little alternative for the customers out there.
Yep. One Garmin means all Garmin if you want connectivity. It's no coincidence that the one non-Garmin product Garmin connects with is ForeFlight - the company with the largest share of the EFB market.
 
The guys who are in early and develop the biggest market share always have a competitive advantage.
Initially, yes. The classic strategy for fighting incumbent advantage is for the challenger company to choose a specific niche and saturate it with support that users in that niche can't get from the bigger company, so that the incumbent become dominant in that small corner, then leverage that dominance to push into other niches, and eventually capture the market.

Avidyne managed the first part (they own the niche of thrift-conscious private owner-pilots wanting to reduce installation costs upgrading from a GNS 430W or 530W to a newer GPS), but they haven't really managed to break out of it yet and challenge Garmin's avionics dominance anywhere else, the way Garmin successfully dethroned Bendix-King a couple of decades ago.

Most of the pilots I know with an IFD installed it as an upgrade to an existing GNS 430W/530W — I know few, if any, who installed an IFD from scratch (even though it's just as capable a unit as the Garmin's GTN).
 
I am buying a certified aircraft with the following avionic :
Avidyne 440
Garmin GMA340
Garmin GNC250
Stratus Appareo xpdr
JPI 900

I have never used a Avidyne before, so I downloaded the ipad simulator to test it out.
So far, I really find a Garmin GN355/175/375 more user friendly. But everybody swears the Avidyne is superior.
I am looking for opinions from people that have actually used either of them, or have selected one or the other for their airplane.
I am planning to add a G3x or Dynon Skyview together with an autopilot. The Dynon autopilot will only be available this year or god only knows when. The Garmin is already available.

I am looking at a few options :
1) just add the Dynon Skyview and wait for the autopilot to arrive. Keep the Avidyne (easier option)
2) add a G3X but not sure how this will go with the Avidyne, and minor detail but, I guess I will need 2 subscription to update. (correct me if I am wrong)
3) replace the Avidyne with a GN355 and install a G3X with Garmin autopilot.

I also need some input as far as cost is concerned. If I replace the Avidyne, it looks like I could sell it for around 9K and buy a GN355 for around 6.5K, but what about install ? Will it be easy since the wiring might already be there, although it might require a new antenna ? In other words, would I save money doing that ?

Thanks for your input
Keep the 440. I have an IFD 550 in my aircraft and it is incredible. Get the I-pad app and learn it as you will come to like it and it's ease of use. There will be no home key pushing to get back to a place you forgot how to get back to.
 
If it ain’t broke, why fix it? I’d go with the current and paid for set up.


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