Panel Avionics Upgrade Options for my Navion

Leo Langston

Pre-takeoff checklist
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llangston1
I am looking at adding a autopilot to my Navion and right now STEC is the only approved & available AP for the Navion. Given that I can obtain a 55X AP I am looking for the best options to equip the plane to "drive" the AP. Right now the plane has an old school basic IFR setup with venturi driven AH and DG, Electric T&B, 2 Narco MK12Bs with GS, King Mkr Beacon and a new Stratus ESGi ADS-B transponder using FF on an iPad mini. There is no panel mounted GPS navigator. I want to replace the Venturis and Vacuum instruments and add a good audio panel/intercom. The plane still has old school analog engine instruments and could use a good recording engine monitor. I have considered G5s, 275s, G3Xs, Aspen 1000s or a DYNON HDX. For radios there are the Garmin 750/650s and the similar Avidynes. So I believe I need at least one GPS and one Nav/GS and 2 comms. I am not IFR rated but would like to equip the plane so I can get my rating. My son flies 767s so he is rated but doesn't fly GA much these days so we just don't know what really works, is not hard to configure/operate in IFR conditions, provides decent redundancy and is readable for old eyes. I don't intend to use the plane for lots of hard IFR flying but would like to be able to punch through cloud layers or shoot an approach when necessary. Yes I know this will be pricey so I am just looking for least expensive (biggest bang for the buck) suggestions and recommendations.This avionics upgrade will be combined with a new metal panel so I can organize the switches and CBs which are currently all over the panel. If I can use at least one of the Narcos that would be fine. We just flew a practice ILS approach a few days ago and it was spot on the LOC & GS. Please no sell the airplane and buy another one recommendations.
Thx in advance
 
2 G5’s and a 650 or 750 (Do you want to pay for the larger display? It is nice) will do all the IFR you end for training and most likely for going any place you want to go IFR. Probably will need an Audio Panel. Could keep one of the Mk12Bs for a backup and send radio.

Brian
CFIIIG/ASEL\
 
I have had a 55X for about 15 years now and have no complainsts. It is driven by a GNS480 (which was the best thing on the market at the time). We were just on the cusps of fancier glass, so I have an old steam gauge KCS55 HSI and an MX20.

I'm probably going to update soon with a Avidyne IFD550. I have gotten really ****ed off at Garmin's service policies over the years and refuse to waste more money on them.

By the way, don't know where you are but there's Heath Aviation avionics shop down in Winona, MS. The guy is an Navion guy. I've flow his Navion that has the Garmin PFD and uses an Aspen as the backup
 
The 275's will do it. I put two in my archer and they drive my 55x just fine. I also have the GMA35 audio which saves panel space. I think Garmin is running a special promo on the 257's now.
 
STEC autopilots are STC'd for airframes, and the cost of the STC to put one in a new airframe approaches the cost of a new unit.
 
I am just looking for least expensive (biggest bang for the buck) suggestions and recommendations.
If you put it in those terms...
I have considered G5s, 275s, G3Xs, Aspen 1000s or a DYNON HDX.
... G5's are the biggest bang for the buck. The rest have more bang, but the bucks go non-linear.
For radios there are the Garmin 750/650s and the similar Avidynes. So I believe I need at least one GPS and one Nav/GS and 2 comms.
You could get a Gamin GNC355 for a good bit cheaper than a GTN or similar Avidyne. The trade-off is that you'd need to keep one or more NAV/GS and the associated CDI plus one of the COM radios. The screen is smaller, but the symbols/lettering drawn on the screen should be about the same size as a GTN.

Or you could get a Garmin GPS175 and keep all of the existing NAV and COM radios, but this would mean making a 2 inch space in the radio stack for it.

The audio panel is mostly a standalone decision independent of all the other upgrades. I'd go with a PMA450b or PMA8000G from PS-Engineering. If you needed a COM radio then you could put in a PAR200A, but that does not sounds like that is the case.
 
here is my .02 and it worth exactly what you paid for it and its your money so i can spend it real easy. everything in it now is old school and not worth keeping if your looking for an upgraded panel. I really don't like putting all my radios in one basket, that's why I really don't like the 650/750. I would go with a 355 com/gps, 255 for the second nav/com giving you redundant comm and nav and a couple of g5's for displays. add a ps engineering audio panel and have a great panel. to top it off a edm 900 engine package.
 
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I too was looking for best bang for buck IFR platform. Keep a Narco for backup and the CDI. Get an IFD540, 2 G5’s and a PMA audio panel. I have the STEC 3100 and love it. Not sure if they are certified for your plane. People have been enjoying the 55X for many years. For engine monitor I got an Insight (twin)G4. It’s good but doesn’t replace old school gauges. If that’s important to you get the JPI that allows replacing.

Whatever you go with, good luck on the upgrades!
 
Minimum-viable expenditure in addition to the STEC-55x that you've already decided on: add a Garmin GPS 175 for $5K (+ installation) and keep your existing avionics. The GPS 175 will drive the STEC just fine. You might need a separate GPSS converter (or buy a GI-275 with GPSS built in if you crave a bit of glass; you'll probably need a modern digital CDI for the GPS 175 in any case).

That's assuming that the Navion is listed on the STC for the Garmin stuff, of course.
 
The GI275 can drive the 55X, but the G5s will need additional LRUs to make it work. With the proper 275 versions (ADAHRS), you will have full legal reversionary capability and can ditch the vac system.

For radios, I'd go with a GTN650 and a GNC255.

If you want an engine monitor, I'd throw a third GI275 in there with the probes for a 6-cyl. It's one of the cooler things the unit will do.

Audio panels are cheap in a relative sense. The installation on any new audio panel will be nearly the same because they really should replace all your adio wiring including new jacks. So if you're going to spend the money, you might as well go with the GMA350C. It's only a few hundred dollars away from the PS unit but will look and play nice with everything else.

I can assure you, if you go to sell the airplane it will be easier to do if the equipment is all the same family vs a Picasso of things that start with "A" or "B."

Product support with Garmin is a lot easier than with other companies. This isn't to say it's always painless.

I have no affiliation with any manufacturer, I'm just telling you what I learned when I was an installer for multiple companies.
 
To my knowledge the STECs (20/30 and 55x) are the only "current manufacture" things STC'd for Navions.
 
To my knowledge the STECs (20/30 and 55x) are the only "current manufacture" things STC'd for Navions.
You only referring to autopilots, right? I see Navion on the G5 and GI275 AML.


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Yes, I was referring to Autopilots (which is why I listed STEC).
 
I heard Garmin, Garmin, Garmin. Putting in a word for the avidyne, people who have flown both say the avidyne is much better for IFR. It keeps up with you in such a way that when you reach for a button, it’s already suggesting what you’re most likely doing.

Go missed? The Garmin makes you hit a button to go missed, which is probably the worst time to look for a button. The avidyne says “we were in landing configuration headed for the runway, but now full power and climbing? Missed.” It changes to missed mode automatically and loads the missed procedure.

of the two, avidyne probably has the better system.
 
Have your son who flies 767s sit with you and both try the Garmin vs Avidyne and see which is more intuitive and similar to what he flies and what clicks for you.
 
Audio panels are cheap in a relative sense. The installation on any new audio panel will be nearly the same because they really should replace all your audio wiring including new jacks. So if you're going to spend the money, you might as well go with the GMA350C. It's only a few hundred dollars away from the PS unit but will look and play nice with everything else.
I just have to chime in. If Leo goes with the GTN series AND wants to install a Push-To-Command (PTC) button to use Telligence for voice commands, then it makes sense to install the GMA35c or GMA350c. But if Leo isn't interested in using voice commands, the prices are virtually the same but there is no comparison with regard to audio panel capability AND ease of use.

Our PMA450B and PMA8000G look GREAT IMHO on top of the GTNs and plays very nicely with GARMIN radios.

An interesting little story about "playing nice".

In 1999 Raytheon required GARMIN and PS Engineering to work cooperatively on an STC. That STC allowed Raytheon to install our audio panels with GARMINs radio. I was very grateful that Raytheon choose our audio panel for their Bonanza and Barons.

But handsome good looks are just on the outside, it's what is inside that REALLY important. Just like us humans!

Thanks POA for giving me this opportunity to start my day off on the right foot.

Mark Scheuer
PS Engineering, Inc.
 
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@mscheuer

The PTC capabilities you've mentioned are indeed the differentiating factor. I've no way of knowing whether the OP knows or cares about it.

But you are correct, other than that added capability, either unit will function just fine.
 
I’ve always liked the Navion! Such a beautiful airplane! As for avionics, you’ve got plenty of space on your panel for a GTN750. If you can justify it, it’s very nice :). I have the remote transponder and remote audio panel. At first I was a little skeptical about not having a stand-alone transponder or audio panel. But it all works really well! Basically everything is controlled through the 750. You can control your audio panel and your transponder from the 750 and save a lot of room. It makes for a very clean look. I’ve got 2 G5’s but I’ve just recently flew a Cherokee 6 with the new’ish 275s. They are amassing! I personally like the square look of the G5’s but the resolution of the 275s is much better! Anyway you go it’s all expensive! Just figure out what you like and bite that bullet.
 
Right now we are leaning toward the Aspen 1000 Pro Max, primarily because it appears to have a better integration with the 55X with the altitude preselect and Flight Mode Annunciation(FMA) included. Then we would go with a Garmin 650Xi (because of the new Smart Glide feature) and one of my old Narco as a backup navcom with either a garmin or PSE audio panel. Keep my Stratus ESGi driving my iPad mini for ADS-B weather and traffic. Does anyone have better knowledge regarding FMA or altitude preselect on a G5 or 275 or a G3X? My son prefers to see what the AP mode is on the PFD and not have to look around for it. He is not a fan of having the PFD in GPSS and the 55X in Hdg mode as that might get confusing in the soup and a source of pilot error. But that might be something we have to live with if thats the only way the 55X will function. I have ruled out the Garmin 500 txi as too costly but if that compares favorably with a Aspen installation I would consider it. These are all the little details that youtube videos don't really answer for us.
 
@Leo Langston The 55x has built-in GPSS circuitry, you just need to ensure that the installer wires to it. That also allows for the arming of the 55x HDG -> GPSS modes.

I'd also suggest you have a good look at the IFD440, before you decide on a GPS.

* Orest
 
I will say the one feature that is leaning me to the 650 is this new Smart Glide feature. I don’t know if that is a gimmick or a real safety feature. Plus I am not sure how it would even work with this Aspen/55X setup. It might not. Avidyne doesn’t currently have it and unless they can develop their own version they may never have it.
 
I will say the one feature that is leaning me to the 650 is this new Smart Glide feature. ....

Remember that you are unlikely to ever use that feature, at least hopefully not!

Everything else in the navigator families, the high level organization, the user interface, the page designs and so on, you will use every time you turn your attention to it. Both will give you a magenta line to fly and direct an A/P, but differ significantly in how you compose and manipulate it.

Both Garmin & Avidyne have simulators to download and test them out, as well as a number of videos to watch. Check them out. You may have a strong preference for one or the other, many folks do.

Once educated, you can make an informed purchase.

* Orest
 
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And if you don't need Smart Glide and already have working NavComs, you can save a lot of money by getting one of Garmin's less expensive GPS navigators like the 175.

Garmin's GTN xi series does have a much higher-resolution, more-vivid display then the decade-old display tech in regular GTNs or Avidyne's IFDs though, so that would be a benefit on every flight if you're set on a full GPS NavCom. (Ditto for the display on Garmin's GI-275 vs the older G5).
 
And if you don't need Smart Glide and already have working NavComs, you can save a lot of money by getting one of Garmin's less expensive GPS navigators like the 175.

Garmin's GTN xi series does have a much higher-resolution, more-vivid display then the decade-old display tech in regular GTNs or Avidyne's IFDs though, so that would be a benefit on every flight if you're set on a full GPS NavCom. (Ditto for the display on Garmin's GI-275 vs the older G5).

IIRC, the rez difference of the xi is about 25%, but the color depth is unchanged, and the latter is often a more significant factor. I suspect it was more a supplier issue than a positive design direction. It was nowhere near the improvement going GNS -> GTN. I've not seen an issue discerning information on the screen of a GTN or IFD, they are bright and daylight immune.

However, the delta between the LCD G5 and the GI-275 is quite significant.

* Orest
 
All I’ll say is that when selecting an audio panel, keep in mind that it is the central nervous system of your avionics suite. Select the right one for your mission and remember, audio control is our one and only passion (other than flying airplanes)

-Mark
 
So if I select the Aspen 1000 ProMax or 2000 to get the MFD, what ADS-B in/out transponder would be the best to provide weather and traffic to the Aspen. I currently have a Stratus ESGi with Foreflight on an iPad mini. I also need a panel GPS so can I use the Garmin 375 or is the 345 a better choice? The L-3 Lynx 9000 seems a little pricey. Will the 375 connect with Foreflight and the iPad without having to buy one of the FlightStream devices? Will I be forced to switch to Garmin Pilot?
 
In trying to upgrade my panel for the least cost, I believe it makes sense to get the engine monitor now so the new panel is cut once without having to cut it for all the old analog gauges and then redo it if I add a primary engine monitor. So to allow for the engine monitor I need to eliminate a 650xi or IFD 440 and go with a Garmin 355 or 375. If I go with the 355 I can take out one of my Narcos but will have to stay with my Stratus transponder and iPad for weather and traffic. If I go with the 375 I need to keep both Narcos for the Comms but I can now get weather and traffic on the Aspen and iPad. I will have to remove the Stratus and try to sell it. Any other suggestions?
 
It won't be easy, but there's now precedent for a field approved GFC500. There's a Myers 200D that recently reported receiving a full blown field approval to install a GFC500. Reportedly wasn't cheap, but they got it done. Steinair did the work. Post on the Myers forum says:

"SteinAir, located in Faribault, MN (KFBL), has obtained a field approval for installation of a Garmin GFC 500 autopilot in a Meyers 200D.

I am very pleased with the performance of the autopilot. Everyone who has experienced it is impressed, including mechanics. The technicians at SteinAir did superb work."
 
I am surprised a local FSDO would even consider an AP field approval but I guess that is good news at least for Meyers owners.
 
So if I select the Aspen 1000 ProMax or 2000 to get the MFD, what ADS-B in/out transponder would be the best to provide weather and traffic to the Aspen. I currently have a Stratus ESGi with Foreflight on an iPad mini. I also need a panel GPS so can I use the Garmin 375 or is the 345 a better choice? The L-3 Lynx 9000 seems a little pricey. Will the 375 connect with Foreflight and the iPad without having to buy one of the FlightStream devices? Will I be forced to switch to Garmin Pilot?

I have the aspen MAX panels, and I swapped from a KT-74 to the GTX345. I absolutely love it. Getting the information on my aspens and my ipad without a separate stratus unit is really nice. It also shows on my 430 but the resolution on it is crappy.
 
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