Why buy a GNS430 over a GNC355?

jd21476

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jd21476
Ive been looking at avionics upgrades and will probably pull the trigger sometime this year. The brand new Garmin GNC355 retails for $6,999 and Sporty's has them for $6,295. This is a brand new modern unit. On Ebay, old and used (still in good condition though) Garmin GNS430's are going for $3,500 to roughly $6k and the 430W is around $5200 to $7500.

So why would anyone get the old Garmin 430W instead of the new 355?
 
No experience with the quality of the touch screen 355.

The 430 is very proven.

You’d have to put hands on both, 355 does seem like a good deal, though I’m not a fan of the touch screen
 
You'd have to be sure you're OK without a NAV radio. Other than that, no reason to get an old 430W instead of the GNC355.
 
If I understand them correctly, the 355 doesn't have the radio or the VOR/Loc/Glideslope features. However the 430W needs an additional transponder to meet the ADS-B requirement.
Did I miss anything?
 
If I understand them correctly, the 355 doesn't have the radio or the VOR/Loc/Glideslope features. However the 430W needs an additional transponder to meet the ADS-B requirement.
Did I miss anything?

The GNC 355 requires a transponder too, so I'm not sure where you're going with that.

And while the GNC doesn't have a Nav radio, it will do RNAV/LPV so it really depends on your needs
 
So from my research, the GNS175 has the NAV only, the GNC355 has the NAV and Radios, and the GNX375 has the NAV and ADS-B (in/out) so the 355 seems to match the 430 the best.
 
So from my research, the GNS175 has the NAV only, the GNC355 has the NAV and Radios, and the GNX375 has the NAV and ADS-B (in/out) so the 355 seems to match the 430 the best.
GPS175 (not GNS175) has GPS only, no NAV radio, no COM radio and no transponder.
GNC355 is the GPS175 with COM.
GNX375 is the GPS175 with ADS-B transponder.
The 430W has GPS, NAV radio and COM radio.

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So from my research, the GNS175 has the NAV only, the GNC355 has the NAV and Radios, and the GNX375 has the NAV and ADS-B (in/out) so the 355 seems to match the 430 the best.
GPS 175 is a GPS navigator only
GNC 355 is a GPS navigator with COM
GNX 375 is a GPS navigator with transponder built in.

So what are you looking for in terms of capability?
 
Personally, I would want a Nav radio in my plane, just in case of GPS issues.

Also, the 430W database updates are a little cheaper.

But if the cost was equal, and I had a Nav/Com to install with it, it would be a tough call (leaning toward the one with a full warranty)

Right now, I would install a non-WAAS GPS unless it was insanely cheap.
 
I did not notice the lack of a nav radio, yeah that’s a big one.
 
So why would anyone get the old Garmin 430W instead of the new 355?

The GNS430 is already 20+ year old technology. I can't see installing one new as a #1 nav today. And non WAAS is a nonstarter with so many LPV approaches available at outlying airports today. If you already have a non WAAS unit, OK, but a new install with limited capability? The install cost for a 430 would rival its acquisition cost, and you would still have old tecnology with a limited support life. The newer units have superior displays and a longer supported life ahead of them.

I have a 430W and already know an IFD440 is in my not too far future.
 
I’d pair a GNC355 with a GNC255 and cover 2 com, and both GPS and VHF nav. If you need ADS-B I’d go for the GNX375, GNC255, and the new PMA’d GTR200B. I wouldn’t go for a 430 unless you get in at a great price and as a W unit. If you really need it in one unit, the GTN or IFD is the way to go. Nothing wrong with a GNS, but they are ancient (but supported) at this point and even the GTNs are getting mid-life (and due a bump soon).
 
No experience with the quality of the touch screen 355.

The 430 is very proven.

You’d have to put hands on both, 355 does seem like a good deal, though I’m not a fan of the touch screen

That’s right, you’d have to live with both of them to truly know the difference. Also don’t overlook the fact that the 430 has an integrated radio that allows you to get the frequency you want without chugging and plugging.

There is a reason for the 430W’s staying power. They are a known entity and there is no indication whatsoever that support for them will end any time soon.

in my career I was involved with a niche software industry in many aspects of the business from development to management to marketing. What of the many things I learned about the aging of technology was that there is a bell curve. On the leading edge of the curve is the person that will stand in the snow and sleep in a tent to be the first to get the newest iteration of a gadget or technology. On the other end of the curve is the person that absolutely won’t budge from his ancient old technology until he’s the last one on the planet that doesn’t have one. Those in the middle of the curve, which is the vas t majority, are those who make sure the technology is mature enough not to be part of the beta test group and know that the technology isn’t significantly outdated to the extent of knowing that the next technology is not drastically superior.

Sure, the 650/750 and the 375 are newer technology with touchscreens instead of buttons and knobs. Is the elimination of buttons and knobs worth the expense and learning curve? This is a question that can only be answered by the person who writes the check and twists the knobs.
 
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That’s right, you’d have to live with both of them to truly know the difference. Also don’t overlook the fact that the 430 has an integrated radio that allows you to get the frequency you want without chugging and plugging.

There is a reason for the 430W’s staying power. They are a known entity and there is no indication whatsoever that support for them will end any time soon.

in my career I was involved with a niche software industry in many aspects of the business from development to management to marketing. What of the many things I learned about the aging of technology was that there is a bell curve. On the leading edge of the curve is the person that will stand in the snow and sleep in a tent to be the first to get the newest iteration of a gadget or technology. On the other end of the curve is the person that absolutely won’t budge from his ancient old technology until he’s the last one on the planet that doesn’t have one. Those in the middle of the curve, which is the vas t majority, are those who make sure the technology is mature enough not to be part of the beta test group and know that the technology isn’t significantly outdated to the extent of knowing that the next technology is not drastically superior.

Sure, the 650/750 and the 375 are newer technology with touchscreens instead of buttons and knobs. Is the elimination of buttons and knobs worth the expense and learning curve? This is a question that can only be answered by the person who writes the check and twists the knobs.
It’s the end of life issue that made it a no brainer to me. Why pay that kind of money for a gadget that is not likely to last another 10 years?
 
Only reason to buy a 430 is if yours dies and you don't want to spring for the installation cost. Perhaps the better decision in this case would be to upgrade to an avidyne.
 
After the 2020 mandate put a huge hole in the pockets of a lot of GA pilots, I think Garmin would be foolish to end factory support for the GNS line. King continued the KX-155 for how many years? And, VOR/ILS is still gonna be around for awhile. A good used GNS430W is a hell of a big bang for the buck at around $6k. And, refurbed/updated units are available that look and operate like brand new. I just got a refurbed unit with a new front end, and all the updates.
 
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Is there anything all in one system that has GPS/COM/transponder....with ADSB?

I have a KX155 for a secondary radio so I would ike an all in one if possible.
 
You want the modern technology, and I'll give you a cautionary tale as to why.

I bought a KLN94 awhile back. Seemed like a really good deal, and a capable unit. I've been flying with it for awhile VFR and have been quite happy. It runs my autopilot and can guide me to where I want to go. I have now started IFR training and need to update the GPS periodically.

The technology for this thing is ancient, mostly from the late 90's. I had to find a computer with a late 90's/early 2000's operating system to download the program that loads the database into the GPS. And I had to use a PC (I'm Mac based) to get the data from Honeywell, who by the way hasn't supported this product in a decade.

Not only are you buying the GPS, but you're buying into the support technology. I'd buy the newest shiniest thing you can, because as least it'll be using today's technology, and not that from yesteryear. When the little PC I got to do all this finally bites the dust I don't know what I'll do. Probably get a new GPS.

That, and you're going to spend a fortune putting the fool thing in your panel. Might as well have a new one for the same price, you get a warranty and everything. Anything goes wrong with your 430 and its tough luck Charley.
 
Is there anything all in one system that has GPS/COM/transponder....with ADSB?

I have a KX155 for a secondary radio so I would ike an all in one if possible.
I would not be happy with an all-in-one....the thought of single point of failure is grounds for nightmares.
 
Here is an unsolicited opinion from a guy with a 430W. I've wished and shopped for a few years now with a desire to replace my 430W that interfaces with my Aspen and Avidyne DFC90 autopilot in my Cessna 182. Newer units are more expensive and have more features. No doubt. For example, airway programming. But with the FlightStream installed I can plan just about everything in ForFlight on the iPad and send it to the 430W to execute. It's like having a fancy updated interface that is really cheap to get new features with on the iPad from ForeFlight.

So like many here, replacing the 430W is a struggle to defend with my configuration. But since this is a new install for you then everything is on the table and there are factors to consider like how long you plan to keep the plane and what features you absolutely must-have.

By the way, with my 430W current setup, I have flown a lot of hard IFR and it has never left me down. You also have to consider how long database support will be around? Maybe forever.

The most comforting advice I can give you is no matter what choice you make, 50 percent of people will think it's the wrong one. Just make the choice that works best for you.
 
You want the modern technology, and I'll give you a cautionary tale as to why.

I bought a KLN94 awhile back. Seemed like a really good deal, and a capable unit. I've been flying with it for awhile VFR and have been quite happy. It runs my autopilot and can guide me to where I want to go. I have now started IFR training and need to update the GPS periodically.

The technology for this thing is ancient, mostly from the late 90's. I had to find a computer with a late 90's/early 2000's operating system to download the program that loads the database into the GPS. And I had to use a PC (I'm Mac based) to get the data from Honeywell, who by the way hasn't supported this product in a decade.

Not only are you buying the GPS, but you're buying into the support technology. I'd buy the newest shiniest thing you can, because as least it'll be using today's technology, and not that from yesteryear. When the little PC I got to do all this finally bites the dust I don't know what I'll do. Probably get a new GPS.

That, and you're going to spend a fortune putting the fool thing in your panel. Might as well have a new one for the same price, you get a warranty and everything. Anything goes wrong with your 430 and its tough luck Charley.

I use my MacBook running Windows XP on parallels to update my KLN90B. Hasn’t been an issue.
 
I don’t think this is the case for the 430 but component comparability might be another reason for continuing to by a 430. For example, my old STEC 50 without GPSS will not work with modern GPS systems. So now I’m looking at upgrading the autopilot as well. But then I’ve heard the new autopilots will not work with my old KX radios and HSI so now those have to be upgraded as well.
 
I don’t think this is the case for the 430 but component comparability might be another reason for continuing to by a 430. For example, my old STEC 50 without GPSS will not work with modern GPS systems. So now I’m looking at upgrading the autopilot as well. But then I’ve heard the new autopilots will not work with my old KX radios and HSI so now those have to be upgraded as well.

Or if you are putting in G5s anytime soon, your STEC AP will still work, with emulated GPSS, through the GAD29B with any of the Garmin or Avidyne navigators.
 
Or if you are putting in G5s anytime soon, your STEC AP will still work, with emulated GPSS, through the GAD29B with any of the Garmin or Avidyne navigators.
This is true however the cost to add GPSS is almost as much as a new autopilot that would have added capability. It’s a rabbit hole for sure.
 
They are ending support when they run out of parts


After the 2020 mandate put a huge hole in the pockets of a lot of GA pilots, I think Garmin would be foolish to end factory support for the GNS line. King continued the KX-155 for how many years? And, VOR/ILS is still gonna be around for awhile. A good used GNS430W is a hell of a big bang for the buck at around $6k. And, refurbed/updated units are available that look and operate like brand new. I just got a refurbed unit with a new front end, and all the updates.
 
I think Garmin would be foolish to end factory support for the GNS line.
I suspect that Garmin's decision on that matter is heavily influenced by parts availability.

Not only are you buying the GPS, but you're buying into the support technology.
That applies to waaaaaay more things than GPS.
 
Only reason to buy a 430 is if yours dies and you don't want to spring for the installation cost. Perhaps the better decision in this case would be to upgrade to an avidyne.

why would you do that when the fixed price repair on the 430W is $1200?
 
Don’t know anything about that. My 430W went belly up about a year ago. It went to Garmin for the fixed price repair. They couldn’t fix it so they sent me a refurbished exchange unit for the same price. Seemed like pretty darn good support to me.
 
Is there anything all in one system that has GPS/COM/transponder....with ADSB?

...

Closest I can think of is a GTN-750 which will control a remote ADSB transponder (335 or 345 remote) from the touchscreen. But that's a lot of AMUs.
 
I don’t think this is the case for the 430 but component comparability might be another reason for continuing to by a 430. For example, my old STEC 50 without GPSS will not work with modern GPS systems. So now I’m looking at upgrading the autopilot as well. But then I’ve heard the new autopilots will not work with my old KX radios and HSI so now those have to be upgraded as well.

Your old STEC 50 without GPSS will absolutely work with a GTN 650. I know a guy with an STEC20 that couples in TRK mode to his 650. It isn't as good as the intercepts with GPSS, but it works with some pilot management.
 
Since a 355 doesn’t have a radio this is an apple to orange comparison. Do you have good reliable radios? Do you understand the advantage of having the radio incorporated with your navigator?
 
Since a 355 doesn’t have a radio this is an apple to orange comparison. Do you have good reliable radios? Do you understand the advantage of having the radio incorporated with your navigator?
The 355 does have a comm radio. It doesn’t have a nav radio.
 
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