Upgrading my Avionic system

lvjuco

lvjuco

Filing Flight Plan
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Orlando, Florida
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Caleb
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Hello to all, Newbie here, so be nice... lol, I am looking to bring my new purchase airplane (C-177 RG II) to better avionics, It got some update in Mid 1990s but Out with the old and welcome the new... But, I will like to used some of the avionics that I have and upgrade the ones that I do really need....

Fully IFR:​

  • Garmin Multi Com GMA 340
  • Apollo 2001 GPS
  • 2 Bendix King TX-155 TSO (replacing the glass shields)
  • Garmin GTX 327 Transponder
  • Stec - 30-2 Autopilot
  • ARC R-546E 300 ADF

​

​

 

I was thinking on replacing one of the Nav/Com with a Garmin GNS530w while removing also the Apollo 2001 GPS, maybe upgrade the STEC-30-2 to a STEC-3100... Comments?​

 
What’s your budget (min/max range)? And how well does your autopilot work?

The 530 is getting old, and the new GFC500 autopilot works very nicely. But it all depends on how much you want to spend. Where are you located?
 
My standard advice:
- first go to

www.hangarflying.com

and re-create as a starting point with the free version of the panel designer your existing panel configuration.
- define a maximum budget
- evaluate the condition of all existing components including the wiring. If the existing wiring is of questionable quality, slide-in replacements may not save as much in installation costs as advertised
- when considering used avionics, have in mind the labor to install the unit might be more expensive than the value of the unit
- never grab a falling knife, meaning do not buy used units with already known or upcoming parts availability issues like the screens for the 430/530
- consider to install a Guardian ipad mount to create a large display for IFR flying


- consider combos like the PS200B (audio plus radio) or the Garmin 375 (GPS plus ADS-B transponder) to save space and some money
- consider Avidyne IFD‘s instead of Garmin units, but be aware that this rules out the Garmin GFC500 autopilot route
 
I never liked the gtn650. The gtn650xi however is a better unit.
Consider if you need a vor/ils on a GTN or one of the less expensive gps only navigators. If you keep one of the tx-155 units you could save a bit by just getting a garmin gps175.
 
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One more thing from my side:
- be consistent with a general idea. Installing a used GNS530 and considering a new S-TEC 3100 at the same time does not make sense to me. If your budget can take such hit (looks like 18k plus installation) then pair the a/p with a state-of-the-art navigator and not with some sort of legacy stuff.
- Unless you really like the old KX-155 do not invest a lot of money in these units in their current condition. Get a quote from a reputable source like Bevan first.
 
The STEC 30 is a decent AP if linked to good GPS with a GPSS link. I'd spend the money on getting the navigation capability up to snuff. ADF - only consuming useful load, get rid of it. Get new GPS Nav/comm - some good suggestions already made. If your budget can handle it, get a second radio that can also track VOR/ILS. Basically replace everything in that stack between the transponder and the audio panel.
I'd also assess the wiring - the visible crimp connectors above the audio panel don't give me a warm fuzzy about how the new stuff was installed. It might make sense to just rip most of it out and start fresh.
Lastly, it makes some sense to figure out how all the new stuff works before updating the AP. The newer GPS will have quite a learning curve and adding a new AP at the same time will complicate it.
I flew with an up to date panel and an STEC 30 for several years and an IFR rating before updating to a GFC500.
 
Taking a step back, what kind of IFR flying do you intend to do and do you want the ability to fly an ILS/LOC or VOR approach?

Second, you’ve discussed the boxes but not the indicators. Are you considering/does the plane already have a PFD such as G5, GI275, or Aspen?

If not, you need to understand doing that as a separate project may not be the best idea.
 
Pinecone said:
530W is nearly end of serviceable life.

And the GTN-650 is SO MUCH nicer and powerful. And the 750 is like the 430 when it came out, game changer.

You can get rid of the ADF, unless you like listening to AM radio. :)
Click to expand...

Agreed, Pinecone! Garmin buttons are notorious for failure and are not easily replaced. If there is any way you can swing it, get a 750xi instead. It's expensive, but it is absolutely top of the line, right now. This will also allow you an easy upgrade path to GI 275s and the GFC 500 autopilot in the future.
 
IMO replace the Apollo with a GPS 175 and replace your vacuum gauges with a pair of GI 275. Right off the bat that gets you a big jump in capability with LPV, removes a major failure mode, and future proofs your setup.
 
AK737pilot said:
My two cents: Ditch the Apollo and one of the KX155s and get a GNC355 (GPS/COM). $7800 for brand new vs. $10k for a used GTN 650.
Click to expand...
I wouldn't do that. You'll lose a NAV radio and gain an IFR GPS. Instead, ditch the Apollo and the GTX327 and get a GNX375. You'll lose nothing and gain an IFR GPS as well as dual-band ADSB-In/Out.
Ed Haywood said:
IMO replace the Apollo with a GPS 175 and replace your vacuum gauges with a pair of GI 275. Right off the bat that gets you a big jump in capability with LPV, removes a major failure mode, and future proofs your setup.
Click to expand...
This is also a good way to go.
 
For IFR your highest priority would be installing WAAS GPS. I would NOT go with a GNS-530. They are great units, but alas, they are at the end of their useful life and critical replacement parts are going to be unobtainium fairly soon. And they use small proprietary memory cards. I second the idea of a GNC355 GPS-COM as a cost-effective option to get IFR GPS and a COM upgrade. Keep a usable KX155 for now for VOR backup and ILS capability. For the full monte get a Garmin GTN or Avidyne IFD unit for GPS/COM/VOR/ILS capability. (This would be my first choice.)

Now, you will need a CDI for your WAAS GPS. Instead of spending money on a mechanical indicator (like a GI-106A/B) I'd strongly consider biting the bullet and getting dual G5s or GI275s. These really make IFR much easier, plus, they will integrate nicely with your legacy STEC autopilot and give you GPSS roll steering.

The ADF is not terribly useful anymore for navigation. You could remove it and gain a few pounds of useful load and reduce some drag by removing the associated antennas.

Longer term, you might upgrade your #2 NAV/COM, but to be honest, I have not used the #2 NAV/COM in my plane to do any navigating in 20 years. It mostly gets used to listen to ATIS and contact ground while talking to ATC or tower on the #1 GPS/NAV/COM. So upgrading the #2 is not a high priority as long as it is working.
 
chemgeek said:
I second the idea of a GNC355 GPS-COM
Click to expand...
And I'll re-iterate what I said earlier: With the GNC355, you gain 1 thing and lose 1 thing. With a GPS175, you gain 1 thing and lose nothing. With a GNX375, you gain 2 things and lose nothing.

But in addition to that, the GNC355 is also a loser from a usability standpoint. With a 175 or 375, you can either use the touch screen to enter waypoints or you can twist the knobs like on a 430/530. With a 355, twisting the knobs changes the COM frequency so the only way to enter waypoints is from the touchscreen. With a 355, one of the data fields is reserved for COM frequencies. With a 175/375, you can configure it to display something else. Also with a 175/375, if you want to get back to the map screen all you have to do is turn the outer knob 1 click to the left. With a 355, twisting the knobs will change the COM frequency and therefore getting back to the map screen takes multiple taps.
 
asicer said:
With a 355, twisting the knobs will change the COM frequency and therefore getting back to the map screen takes multiple taps.
Click to expand...
Twisting the outer knob switches between map, flt plan, and nearest (and these are somewhat configurable) and the inner knob changes the map zoom - same as for the 175/375, I believe.

Push the knob briefly, then you’re changing comm freq. Push it briefly again and you’re changing comm volume. Push it a third time and you’re back to the map. At any time, long push and you flip-flop frequencies.

Some touch screen usage is inevitable to use all functionality but there’s actually more that can be done with just the knobs than at first glance.
 
lvjuco said:
View attachment 142521
Click to expand...
Count me as another one happy to spend other people’s money! :D

While I’m very happy with my 355, in your situation and at the start of plane ownership, there are several paths you could take.

We don’t see your display but I fully agree with putting in two GI 275s for AI and HSI. They’ll drive your STEC, which you can keep and will let you dump your vacuum system. Ditch the ADI and put in a 275 as an engine monitor. Get rid of the JPI and the four cylinder monitors and put a panel-mounted Aera 760 over there.

Swap the Apollo and transponder for the 375. It will share ADS-B In with the Aera, which will let you see traffic and weather in a much bigger screen than the 375. You will be delighted to be able to loop NEXRAD on a big screen to see which way to go.

Either leave the comms alone or consider one or two 215s or the Trig TY96 (and maybe a TX56A as a second radio but with Monitor, a second radio isn’t essential, IMHO). I have the 215 and it’s so-so. For the money, the Trig may have been a better route.

Good luck! This is an awesome but expensive time to be making the dream panel!
 
lvjuco said:
Hello to all, Newbie here, so be nice... lol, I am looking to bring my new purchase airplane (C-177 RG II) to better avionics, It got some update in Mid 1990s but Out with the old and welcome the new... But, I will like to used some of the avionics that I have and upgrade the ones that I do really need....

Fully IFR:​

  • Garmin Multi Com GMA 340
  • Apollo 2001 GPS
  • 2 Bendix King TX-155 TSO (replacing the glass shields)
  • Garmin GTX 327 Transponder
  • Stec - 30-2 Autopilot
  • ARC R-546E 300 ADF

​

​

Click to expand...
RG II ?? I’ve never heard of that before. What’s the difference in a II ?
 
lvjuco said:
Hello to all, Newbie here, so be nice... lol, I am looking to bring my new purchase airplane (C-177 RG II) to better avionics, It got some update in Mid 1990s but Out with the old and welcome the new... But, I will like to used some of the avionics that I have and upgrade the ones that I do really need....

Fully IFR:​

  • Garmin Multi Com GMA 340
  • Apollo 2001 GPS
  • 2 Bendix King TX-155 TSO (replacing the glass shields)
  • Garmin GTX 327 Transponder
  • Stec - 30-2 Autopilot
  • ARC R-546E 300 ADF

​

​

Click to expand...
i'd swap the apollo for a gnc355
or if you just need a big unit, yank one of the 155s and the apollo for a gtn650xi

i'd splurge for a gnx375 - adsb in/out and backup gps, don't really need but adsb in/out 8)
you can get the same benefit by using your tablet and a gdl50 or something so this isn't really necc

i wouldn't do the 530, it's old and after install it'll prob be the same cost as a gnc355.

remove the adf

if the autopilot works, leave it, otherwise trutrak, gfc500 or heck i even think you have a choice of trio.

save a little bit of cash for when mrs cfo finds out an wants equivalent upgrades
 
luvflyin said:
RG II ?? I’ve never heard of that before. What’s the difference in a II ?
Click to expand...
From Wikipedia, the font of all human knowledge:

IMG_7846.png

Sounds like it was primarily a “preferred options package”
 
Llewtrah381 said:
Twisting the outer knob switches between map, flt plan, and nearest (and these are somewhat configurable) and the inner knob changes the map zoom - same as for the 175/375, I believe.
Click to expand...
Ah yes, I remember now. With the 175/375, the outer knob switches between map, terrain and nearest. That's because those have a dedicated fit plan button while the 355 does not. Furthermore, the 175/375 have an on-screen CDI while the 355 does not. Pushing the knob from the map screen quickly toggles the data fields on and off with the 175/375. And it's possible to enter a D-> waypoint and activate it without ever touching the screen while the 355 cannot.

I still maintain the the 175/375 has the edge on usability.
Llewtrah381 said:
Push the knob briefly, then you’re changing comm freq. Push it briefly again and you’re changing comm volume.
Click to expand...
My personal preference is for a dedicated volume knob. There's a number of situations where I want to be able to adjust it up/down and/or toggle the squelch as quickly as possible.
 
asicer said:
still maintain the the 175/375 has the edge on usability.
Click to expand...
Depending on the situation, I think you’re right more times than not. In my case I was looking to upgrade a 300XL and the 355 was more or less identical in function and form. At the time I already had a GDL 50 feeding my Aera 660, so ADS-B in wasn’t a concern. I also had a transponder I thought was working but it was dying. Based on this discussion I think a 375 would have been a good way to go plus adding a Trig Nav/Comm and a Trig Comm.

I really think a 660 or, even better if the panel space is available, a 760 as part of the mix is great; none of the 175/355/375s have big enough screens to make traffic and especially weather ideal.
 
luvflyin said:
RG II ?? I’ve never heard of that before. What’s the difference in a II ?
Click to expand...
As mentioned above the Cessna "II" designation indicated an option package. Mainly an IFR avionics setup (Cessna brand radios). I co-owned a C185 II many years ago.

Lots of great info/suggestions in this thread. I'm hoping to do a similar upgrade to my RV.
 
I haven't flown with a lot of autopilots, but I have flown with and like the STEC-30. It's simple, it doesn't take up any space, and I find the interface intuitive. If it'll work with whatever else you put it I'd keep it.

I don't know enough about different GPS models to recommend anything in particular, but agree with the above posts on switching to something relatively new and that supports WAAS as well as replaces the top nav/com you have. If it works, I'd keep the second nav/com rather than upgrade or lose it.

I'm not sure if anyone was suggesting it, but I wouldn't put in two gps. To me it just eats panel space and $ without much increase in redundancy or ease of use. But that's just me.

I wouldn't get rid of the ADF, and I'm probably in the minority on that. The reason I'd keep it is because it only takes up one panel spot and a little bit of weight. Of the non-RNAV approaches around here, easily more than half require radar, DME or ADF. If GPS becomes temporarily unavailable for whatever reason, ADF gives you some options for ILS or LOC approaches that you couldn't do otherwise. This may just be an around this area thing, because of the hills and lack of working VOR's, I don't know...and I am a bit of a baby on wanting multiple options.

Congrats on the new plane! I know a guy that has a Cardinal, and he loves it.
 
Agree that first you need to figure out what will match your flying now and in the future.

How long will you have this plane? A year or two? Or 10-20?
-- If this is your "last plane", then bite the bullet, buy what you need, and enjoy it.

Do you do $100 hamburgers, or will you mostly do X Country? Are you IFR rated? If not, are you planning to get and maintain your IFR rating?
-- If X country and IFR, you might want to add autopilot and some GI 275's or a G3 to the possibilities.
-- In any case, my 2 cents is to have dual coms, but you can get away with one Nav radio.

Figure out your needs, then start making your list. Only after your list is done, then start figuring out where you want to put things.
 
lvjuco said:
Hello to all, Newbie here, so be nice... lol, I am looking to bring my new purchase airplane (C-177 RG II) to better avionics, It got some update in Mid 1990s but Out with the old and welcome the new... But, I will like to used some of the avionics that I have and upgrade the ones that I do really need....

Fully IFR:​

  • Garmin Multi Com GMA 340
  • Apollo 2001 GPS
  • 2 Bendix King TX-155 TSO (replacing the glass shields)
  • Garmin GTX 327 Transponder
  • Stec - 30-2 Autopilot
  • ARC R-546E 300 ADF

​

​

Click to expand...
We just finished an install on a Cardinal and he went with Dual G5s, GTN 650Xi, and a GFC 500 Autopilot. He already had a GTX 345 and a KX 155. Turned out really nice! Let me know if I can help you with pricing or any questions you might have.
 
Avionics overwhelm me and I'm not even in the market yet! All of the different models from Garmin alone is amazing.

I have a 430W and Sarasota Avionics has a upgrade package for $11K which includes installation in most cases. This has my interest. I've got a ton of hours for a VFR-only pilot. I've never owned an IFR capable plane until I bought my 182 a couple of years ago, and it's time that I start learning! But, before I start training, I think I'd like something a little user friendly. Watching my friend use his new Garmin and how it interacts with Foreflight... much simpler than using a 430!

Not interested yet, but I'll keep watching and learning from you guys!
 
OP hasn't posted since the first three posts. @lvjuco any response or anything to add?
 
write-stuff said:
Agreed, Pinecone! Garmin buttons are notorious for failure and are not easily replaced. If there is any way you can swing it, get a 750xi instead. It's expensive, but it is absolutely top of the line, right now. This will also allow you an easy upgrade path to GI 275s and the GFC 500 autopilot in the future.
Click to expand...
Mine plane came with a 650. Coming from 430s it was amazing. Swapped for a 650Xi. Even better.

New panel still has the 650Xi, but added a 750Xi. GAME CHANGER. It is an amazing piece of equipment to fly behind.
 
OP has not been back to follow up yet. Lots of good ideas here, but it would sure help if we had a better idea of mission and ballpark budget.
 
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