Opinions on planned avionics upgrades/changes

nrimmer

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nrimmer
I recently finished my instrument rating and I am looking to upgrade the avionics on my Cessna Cardinal to make it more IFR capable and generally updated. I am fairly fixed on sticking with Garmin so it all ties into my G5s. Looking for some opinions on the below planned changes:

Currently have:
Audio Panel: KMA 24
Nav/comm 1: Narco Mk12D w/glideslope
Nav/comm 2: TKM 300mx w/o glideslope
Transponder: GTX 335
DME: KN64
GPS: Aera 660 hard wired

Planned changes:
Audio Panel: GMA 340 or 345. A friend has a nice used 340 he will sell me for $700. Not sure if the 345 features are worth an extra $1000. Already have an intercom system and Bluetooth in my Bose headsets. Thoughts?

Nav/comm 1: I want to keep one VHF receiver and ILS capability. Debating whether to keep the Narco Mk12D as backup to the new below unit, or the other option would be to spend the extra $3800 and upgrade to a GNC 255. 255 indicator would be my G5s so no extra cost there. Thoughts?

GPS/comm: Replace MX300 with a GNC 355. This is the one item I’m fairly certain of. Indicator will be my G5s.

Transponder: Obviously keep GTX 335 as it is only 2 years old. Use a portable ADS-B in tied to my iPad.

DME: Debating whether to keep or ditch it while we’re gutting the stack. The idea of a full ground based nav system is nice, but in reality I suspect that I will never turn it on once the panel mounted GPS is installed and they are still worth some money on eBay. Thoughts?

VFR GPS: Debating whether to keep the Aera 660. I have the stack space, but always fly with an iPad for approach plates and as a backup GPS. It seems like three touch screen GPS units onboard (four including my iPhone) is overkill, but I see about half the guys keep the portables even with panel mount GPS - maybe more applicable to the older IFR GPS units that were more clunky to use. Thoughts?
 
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Do you already the 2 G5’s installed? Once you get to GPS/RNAV I wouldn’t pay for DME or an ILS unless it’s already installed, keep it though.

I recently got the simple but capable GPS-175 & dual G5’s, kept the radios, newest is a late model KX-155. The GNC-355 was in the running. Kept my KMA-24 audio panel. They did add a two slot USB charging port.

I have an ILS off the kx-155, works fine. For what I do, this has been fine. Trying to keep costs reasonable was a factor of course. When I want weather I use Garmin Pilot, IPad mini and a GDL-50. The GPS-175 & Garmin Pilot have a great relationship, talk to each other often, when I ‘approve’ the conversation.

There is a lot more out there, I can be happy as somewhat of a minimalist though.
 
GMA 340 or 345.
Going that route buys you slide-in options in the future. 3D audio and the USB charge port on the 345 is nice and might just be worth the extra $1000. However, I'd take a look at a PS Engineering product as an alternative to the 345.
he other option would be to spend the extra $3800 and upgrade to a GNC 255. 255 indicator would be my G5s so no extra cost there.
The GNC255 has a digital output. The G5 cannot take an analog input.
Debating whether to keep the Aera 660.
An aera 660 hardwired to the (planned) GNC355 and configured for MapMX can do things a Bluetooth connected tablet cannot, such as draw approaches and holds.
 
BTW, you didn't mention anything about an autopilot. That's going to affect some of the decisions, particularly the VHF NAV radio.
 
Do you already the 2 G5’s installed? Once you get to GPS/RNAV I wouldn’t pay for DME or an ILS unless it’s already installed, keep it though.

Yes G5s are already installed.

Going that route buys you slide-in options in the future. 3D audio and the USB charge port on the 345 is nice and might just be worth the extra $1000. However, I'd take a look at a PS Engineering product as an alternative to the 345.

The GNC255 has a digital output. The G5 cannot take an analog input.

An aera 660 hardwired to the (planned) GNC355 and configured for MapMX can do things a Bluetooth connected tablet cannot, such as draw approaches and holds.

A GNC255 would be tied into the G5s. Sticking with the Narco I would keep the existing indicator. Drawing approaches and holds is what I was looking for. If there are real functional benefits then I will probably keep the 660, but if it's just another shiny screen then I would probably sell it.

BTW, you didn't mention anything about an autopilot. That's going to affect some of the decisions, particularly the VHF NAV radio.

TruTrak Vizion installed, so it will not follow VHF nav, but I don't mind hand flying those approaches.
 
TruTrak Vizion installed, so it will not follow VHF nav, but I don't mind hand flying those approaches.
G5 installation manual has this under "Installation Limitations":
•cannot interface with dual navigators if G5 is interfaced with a non-Garmin autopilot
 
Yes G5s are already installed.



A GNC255 would be tied into the G5s. Sticking with the Narco I would keep the existing indicator. Drawing approaches and holds is what I was looking for. If there are real functional benefits then I will probably keep the 660, but if it's just another shiny screen then I would probably sell it.



TruTrak Vizion installed, so it will not follow VHF nav, but I don't mind hand flying those approaches.

Will it fly a ILS? The VOR/NDBs all can just be flown with the GPS while monitoring a tuned nav head, but having a autopilot that can’t fly a ILS is a large gap, far more critical than 3D audio
 
The GMA340 is just fine. It will do all the basic things you need in an audio panel. I have one and feel no burning need to upgrade it. The GNC355 will give you a primary WAAS GPS that can drive GPSS on the G5s. I'd just keep the Narco as a secondary for ILS/VOR and leave it at that for now. IFR you will be using the GPS 99% of the time. The DME is redundant with the GNC355. You might as well save weight and panel space. I would keep a hard-wired portable GPS as an emergency GPS backup and secondary WX display. I have an ancient but capable AERA 510 that is mounted on the canopy bow and hardwired to my GNS-430. It is set up to automatically crossfeed with the GPS and can also display XM-WX. It is incredibly handy for evaluating weather, calculating winds aloft, or fiddling with alternate routing, as well as being an emergency backup for navigation and weather display.
 
How much hard IFR do you expect to be doing?

I have a GTN 650, dual G5's, GTX 345 and GMA 345. I also have a GNC 255 that was connected to my existing CDI. I like that I can fly all approaches using the GTN 650 which is connected to the autopilot. If necessary, Nav2 is completely independent from all the devices connected to the 650.

Instead of the GNC 355, I'd take a good look at the GTN 650Xi. I find that setting the OBS on the G5 is awkward. If possible, keep an existing OBS connected to Nav2. Since you have it, I'd also keep the DME. It will increase your options if the primary radio fails.
 
Install the GNC 355 and keep the Narco as #2 Comm and the VHF navigation receiver. Your G5s and autopilot setup cannot legally display two separate navigation radios. Your TruTrak cannot follow a VHF navigator either.

If you really want GPS and VHF nav display on the G5 a 650/750 garmin is the way to go.
 
While doing all this work, you should install some USB ports.
 
While doing all this work, you should install some USB ports.
I've been curious about this. If a plane already has an installed 12v socket (used to be called a "cigar lighter"), what would be the advantage of installing usb ports over just using a high quality 12v-to-usb adapter? Does it have to do w/ dotting the Ts and crossing the Is of regulations more than function, or is there more to it?
 
I've been curious about this. If a plane already has an installed 12v socket (used to be called a "cigar lighter"), what would be the advantage of installing usb ports over just using a high quality 12v-to-usb adapter? Does it have to do w/ dotting the Ts and crossing the Is of regulations more than function, or is there more to it?

It's a long time tradition here to "spend" other people's AMUs.
Subversive behaviour like yours, no matter how practical, will be reported if it persists.
Think of the damage you could be doing...people might get the impression it's okay to pursue avionics upgrades, and maybe even purchase an entire airplane, without coming here and starting a thread first. Horrors!
 
I've been curious about this. If a plane already has an installed 12v socket (used to be called a "cigar lighter"), what would be the advantage of installing usb ports over just using a high quality 12v-to-usb adapter? Does it have to do w/ dotting the Ts and crossing the Is of regulations more than function, or is there more to it?
Some of the plug in ones are noisy. I flew a rental that had a USB plug in the 12v socket, and you could hear it in the headsets.
 
Some of the plug in ones are noisy. I flew a rental that had a USB plug in the 12v socket, and you could hear it in the headsets.

Some reasons -

Noise can be an issue.
Some cigarette lighter adapters won't produce enough power to keep a large tablet charged.
I like having the power on the pilot's side so there are less wires stretching across the cockpit.
Compared to the cost of the avionics upgrades, this will be minimal.
With all the modern, portable electronic devices (tablets, cameras, ADSB receivers, phones) can you really have too many USB ports?
 
I've been curious about this. If a plane already has an installed 12v socket (used to be called a "cigar lighter"), what would be the advantage of installing usb ports over just using a high quality 12v-to-usb adapter? Does it have to do w/ dotting the Ts and crossing the Is of regulations more than function, or is there more to it?

Not only are the 12V socket chargers often sources of electrical noise, the 12V sockets themselves are not always well-grounded or noise isolated. A quality panel mount USB charger will deliver a solid 2.4A-3.0A @ 5 V (depending on whether you install USB-A, USB-C or a combo) with no electrical noise. In addition, you can site the charging unit to keep wires out of the way in the cockpit. I have mine mounted on the center console between the pilot and copilot in the space where the ashtray would have gone in the original installation. When I replaced the console plastic, I repurposed that spot for a Stratus dual-port charger. It will keep a phone and tablet fully charged during flight operation.
 
Gosh, I just have to chime in when it comes to audio panels.
Check the back page out, this shows you the advantages between the PMA8000BT ($1495) and the GMA340
https://www.ps-engineering.com/assets/docs/NewHeightsFlyer.pdf
Hope you might give me a call if you should be leaning towards the GMA345, there are a couple of things you should know.
800-427-2376
-Mark
 
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Gosh, I just have to chime in when it comes to audio panels.
Check the back page out, this shows you the advantages between the PMA8000BT ($1495) and the GMA340
https://www.ps-engineering.com/assets/docs/New Heights Flyer.pdf
Hope you might give me a call if you should be leaning towards the GMA345, there are a couple of things you should know.
800-427-2376
-Mark
Mark,

I don't think you included the correct link... it's broken when I click on it. This may be what you meant to put up...

https://www.ps-engineering.com/assets/img/Compare.jpg

Also, your site lists the PMA8000BT at $1795. Are you offering us a deal right now? ;)
 
Thanks MuseChaser, I have actually uploaded (and created a link) of our latest Plug N Play comparison.
-Mark
 
Audio Panel: GMA 340 or 345. A friend has a nice used 340 he will sell me for $700. Not sure if the 345 features are worth an extra $1000. Already have an intercom system and Bluetooth in my Bose headsets. Thoughts?

FYI, any of the newer audio panels will have a pretty full-featured intercom system built in, with various isolation modes that you will find useful. A separate intercom system will be unnecessary and possibly complicating. I don't know the age of your audio installation, but the new panels are stereo-compatible. When I replaced my audio panel, the audio jacks were all updated to accept the stereo audio plugs.
 
FYI, any of the newer audio panels will have a pretty full-featured intercom system built in, with various isolation modes that you will find useful. A separate intercom system will be unnecessary and possibly complicating. I don't know the age of your audio installation, but the new panels are stereo-compatible. When I replaced my audio panel, the audio jacks were all updated to accept the stereo audio plugs.
Good to know, thank you!
 
I got rid of my KN64 DME when I installed my GTN 650 gpsnav in 2017. Most of the time I have no regrets, but every once in a while I get a wee bit nostalgic.

It sounds like you've made good, economical choices.

Remember that the TT/AeroCruze 100 is not certified to be paired with the GPS for any IFR approaches (though it will fly RNAV approaches in an emergency) — they got it to market faster by skipping approach certification. It's probably legal to use it in track mode above 700 ft AGL, though, and to follow the approach by making small tweaks to the selected track, since it wouldn't violate the "no-coupled-approaches" ban in the AFMS. I'd talk to your instructor or examiner in advance about that if you're doing an instrument proficiency check, just to make sure you're both on the same page.
 
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