Upgrade Help- VFR to IFR

in the last year i've installed 2x g5 and a gnc355a. the plan was to go g3x so g5's made more sense.

i thought about the 650 but except for screensize it really didn't add anything, i already have a radio with vor/ils.
actually, the 355 added more utility as it came with the ability to transfer flight information wirelessly.

As for size of the 355, it's not horrible, I only really use the navigators to change radio frequencies, everything else is thru Garmin Pilot and the G5s. Turns out flightstream is the killer feature of the 355 box.
 
in the last year i've installed 2x g5 and a gnc355a. the plan was to go g3x so g5's made more sense.

i thought about the 650 but except for screensize it really didn't add anything, i already have a radio with vor/ils.
actually, the 355 added more utility as it came with the ability to transfer flight information wirelessly.

As for size of the 355, it's not horrible, I only really use the navigators to change radio frequencies, everything else is thru Garmin Pilot and the G5s. Turns out flightstream is the killer feature of the 355 box.
Flightstream is a micro SD card with WiFi built in it for $1600?
 
Maybe it's a firmware upgrade away. Maybe it isn't. Do you feel lucky? :)
Going with the G5 haha I’ll be fine with that, because it’s a backup, my main focus is the g3x. I’ll survive.
 
Flightstream is a micro SD card with WiFi built in it for $1600
it's built into the gnc355, allows bi directional flightplan / flight info transfer.
no crazy expensive wifi cards necc
 
The GTN-x50Xi with a Flight Stream 510 allows wireless updating of the databases.

The larger the screen, the more you will use it. :)
 
Once you get your Instrument Rating you’ll find yourself filing for every X Country, regardless of IMC or VMC.
 
Once you get your Instrument Rating you’ll find yourself filing for every X Country, regardless of IMC or VMC.
...until you try to plan a flight through a mountain pass.
 
Have flown many IFR hours using a stack that is a 750 or 650 over a 255A in three different airplanes over the last ten years. Have never seen the need for a second GPS, and the 300XL is non-precision only anyhow. GTN750 or 650 drive the HSI (I like the 275 now, but have G5 in one plane and 275 in the other and they are both great. The 275 fits flush in a standard hole and is more expensive of course).

The labor and trauma of tearing into a panel is such that like to do it just once. So a 650 + 255A + 275 + GI106 + 510 or 210 and you are pretty much set.

The 175 series is very nice; have not had an issue flying IFR with it at all. The sync'ing with an iPad is glorious.
 
Doesn’t the G275 allow transfer of flight plans / provide a gateway to the GTN?
 
Doesn’t the G275 allow transfer of flight plans / provide a gateway to the GTN?
Updating databases through Garmin Pilot to the GTN750/650, yes. Unfortunately sync'ing flight plans still requires a 510 or 210 to provide the Connext feature. Just went through this as thought since I have a 275 and a 650 in one plane and thought it could transfer the flight plans, but no joy. Everytime I put the 1500$ 510 card in my Spruce basket I end up taking it out!
 
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I'm not sure what your budget is and you didn't mention what your current VOR display is. Typically you'll want to be able shoot RNAV, ILS, Localizer, and VOR approaches. With your current panel, you'd just need a GPS like like a GTN-650, and then you could get something like a used GI-106 for an CDI. That's probably the most barebones upgrade you could do.

Up a notch from that, maybe rip out your vacuum system and get a pair of G5s to use as your AI and HSI, also driven from the 650.
 
Excellent clarification - thanks.
 
Updating databases through Garmin Pilot to the GTN750/650, yes. Unfortunately sync'ing flight plans still requires a 510 or 210 to provide the Connext feature. Just went through this as thought since I have a 275 and a 650 in one plane and thought it could transfer the flight plans, but no joy. Everytime I put the 1500$ 510 card in my Spruce basket I end up taking it out!
don't know about the 650 but the database updates for a 355 using an sd card is so easy and fast, i just couldn't imagine paying for a 510. i wonder what is so special about the 510 the wifi/bluetooth cards from my comp/cameras are at most 100$ what could possibly be worth 15x the price
 
I think the idea of a 510 is to send the flight plans. But I also think the G275 can talk to / send a flight plan to a GNC355 without need for the 510.
 
I think the idea of a 510 is to send the flight plans. But I also think the G275 can talk to / send a flight plan to a GNC355 without need for the 510.
Think of a GNC355 as having a built-in FS210 for no extra cost. Think of a GI275 as having a built-in FS510 for no extra cost, but minus FS210 capability (FS510-FS210=FS300?).

OK, yeah. That's a massive oversimplification.
 
don't know about the 650 but the database updates for a 355 using an sd card is so easy and fast, i just couldn't imagine paying for a 510. i wonder what is so special about the 510 the wifi/bluetooth cards from my comp/cameras are at most 100$ what could possibly be worth 15x the price
Agree if talking about the 175/335/355 - they are a newer generation and have the functionality of the 510 built in. While the card is very easy to pull out and upgrade, the new units can also be flashed wirelessly, but only through Garmin Pilot. All can transfer flight plans out of the box to/from either Pilot or FF.
 
I'm not sure what your budget is and you didn't mention what your current VOR display is. Typically you'll want to be able shoot RNAV, ILS, Localizer, and VOR approaches. With your current panel, you'd just need a GPS like like a GTN-650, and then you could get something like a used GI-106 for an CDI. That's probably the most barebones upgrade you could do.

Up a notch from that, maybe rip out your vacuum system and get a pair of G5s to use as your AI and HSI, also driven from the 650.
Funny you mention this. I spoke with my avionics guy and explained what I was thinking. He stopped me and says "we can do that, but keep in mind that it will nearly double the cost of our initial talk". What I didn't realize was that I would have to get a second G5 and take out the entire vacuum system. He says my suggestion was way more than I needed to get my IFR ticket, and suggested I get proficient in flying IFR before investing that much money

He's going to install the 355 and find a used heading indicator that interfaces with the 355. He said let's talk in a year or two if we want to go full upgrades with swapping out for dual G5/275 and removing the vacuum system, electronic flight display, and autopilot
 
Funny you mention this. I spoke with my avionics guy and explained what I was thinking. He stopped me and says "we can do that, but keep in mind that it will nearly double the cost of our initial talk". What I didn't realize was that I would have to get a second G5 and take out the entire vacuum system. He says my suggestion was way more than I needed to get my IFR ticket, and suggested I get proficient in flying IFR before investing that much money

He's going to install the 355 and find a used heading indicator that interfaces with the 355. He said let's talk in a year or two if we want to go full upgrades with swapping out for dual G5/275 and removing the vacuum system, electronic flight display, and autopilot
Not sure what you mean by heading indicator to interface with 355. But if getting a 355, IFR will be greatly enabled by getting an HSI in addition - either a single G5 or a single 275. Latter is more expensive, but if and when you do further work it may play a little better depending.

Tearing out the vacuum system is not essential to IFR - unless you are getting a G500 AP, your vacuum AI will provide about the same amount of information as an EFIS one. I have a vacuum AI, an EFIS AI, and neither talk to the GTN650. But the HSI sure does.
 
Agree that an HSI helps. And dual G275s and an AP is great.

But for IFR training without a HSI using a classic mechanical CDI, Attitude Indicator, and a classic DG is a great way to learn Instrument Flying.

And learn how to use the VOR radio system.

It’s going to be expensive enough anyway LOL. After a year or so, and getting a much better idea of what IFR flying is, he might want a G3X for example.
 
Agree that an HSI helps. And dual G275s and an AP is great.

But for IFR training without a HSI using a classic mechanical CDI, Attitude Indicator, and a classic DG is a great way to learn Instrument Flying.

And learn how to use the VOR radio system.

It’s going to be expensive enough anyway LOL. After a year or so, and getting a much better idea of what IFR flying is, he might want a G3X for example.
Think that's debatable - in this day and age of EFIS HSI, might as well get the best situational awareness presentation from the get go. Have done it both ways all across the country and countless times to minimums, there's no doubt that it's much easier, particularly when hand flying, to have an HSI.

No one is tearing out a TC to put in a T&B because it might teach some raw skill a little better.

But everyone has their viewpoint - personally I never saw the sense of going whole hog with a TV-sized screen if already have a couple -275s and a modern navigator ± AP. Each to their own "optimum."
 
Spot on. I’m getting a pair of G275s installed, but I originally trained on a standard DG. Good training because not every airplane I’ll fly in will have an HSI. But definitely looking forward to having the HSI.

I might someday get full glass. Or not.

The only reason I mention the VOR training is because someday you might need that back up.
 
But everyone has their viewpoint - personally I never saw the sense of going whole hog with a TV-sized screen if already have a couple -275s and a modern navigator ± AP.
I did my IR in a WAAS G1000/GFC700. Then I started flying a plane that, except for an older EHSI and a GNX375, was all steam gauges with a wing leveler. At first, I was afraid to IFR but it turned out to be a pretty easy transition. Add in a portable and one flight with a safety pilot and I was proficiently flying IMC in practically no time at all.
 
I did my IR in a WAAS G1000/GFC700. Then I started flying a plane that, except for an older EHSI and a GNX375, was all steam gauges with a wing leveler. At first, I was afraid to IFR but it turned out to be a pretty easy transition. Add in a portable and one flight with a safety pilot and I was proficiently flying IMC in practically no time at all.
Surprisingly a wing leveler gets you about 85% of the autopiloting one needs.
 
A question here before I ask my avionics guy and potentially make a fool of myself again!

If I got the 355 installed, I have an extra cutout in my panel. Couldn't I get a G5 or 275 with HSI to coordinate with the 355, and keep my current vacuum heading indicator, attitude, etc as is? Or is there a functionality with the 355 that I'm not understanding?
 
The GNC 355 is basically a 175 but with a com radio.

The GNC 355 will work just fine with your current mechanical CDI.

On the other hand, if you get a G275 (or a G5) configured as an HSI, the new G275 also works with the GNC 355 to function not only as an HSI but as a CDI for approaches, etc. It does both functions, displays both sets of data at same time. The GNC 355 can only drive either the old mechanical CDI or the new G275/G5, but not both.

You still need the vacuum system to drive your mechanical Attitude Indicator. You could get a second G275 configured as a AHRS, at which point you could delete the vacuum system.

Nav Radio and Com 2———

Do you have a second com and nav radio? My personal opinion is that you need at least one Nav radio as a back up. You could dedicate the old mechanical CDI to the Nav radio, and the G275 to the GNC 355.

If you didn’t get a G275, you’d have to have the new GNC 355 drive the old mechanical CDI, and see if your avionics guy could somehow add a switch to change from GPS to VLOC.

Unlike the GTN 650xi, the GNC 355 does not have a built in GPS/VLOC switch.
 
If I got the 355 installed, I have an extra cutout in my panel. Couldn't I get a G5 or 275 with HSI to coordinate with the 355, and keep my current vacuum heading indicator, attitude, etc as is?
In short, yes. You can even use a GI275 as a CDI rather than an HSI.
 
The GNC 355 is basically a 175 but with a com radio.

The GNC 355 will work just fine with your current mechanical CDI.

On the other hand, if you get a G275 (or a G5) configured as an HSI, the new G275 also works with the GNC 355 to function not only as an HSI but as a CDI for approaches, etc. It does both functions, displays both sets of data at same time. The GNC 355 can only drive either the old mechanical CDI or the new G275/G5, but not both.

You still need the vacuum system to drive your mechanical Attitude Indicator. You could get a second G275 configured as a AHRS, at which point you could delete the vacuum system.

Nav Radio and Com 2———

Do you have a second com and nav radio? My personal opinion is that you need at least one Nav radio as a back up. You could dedicate the old mechanical CDI to the Nav radio, and the G275 to the GNC 355.

If you didn’t get a G275, you’d have to have the new GNC 355 drive the old mechanical CDI, and see if your avionics guy could somehow add a switch to change from GPS to VLOC.

Unlike the GTN 650xi, the GNC 355 does not have a built in GPS/VLOC switch.
Well the plane already has two mechanical CDIs, one hooked up to my 300xl navcomm gps and the other to my ils/vor receiver. I also have a spare, unused cutout. My thought was to keep everything how it is, but install the 355 while adding the 275 HSI to the unused cutout, therefore having the 355 coordinate with the 275

Would that work? Or are you saying that the HSI can't also function as a CDI coordinating with the 355 gps?
 
A question here before I ask my avionics guy and potentially make a fool of myself again!

If I got the 355 installed, I have an extra cutout in my panel. Couldn't I get a G5 or 275 with HSI to coordinate with the 355, and keep my current vacuum heading indicator, attitude, etc as is? Or is there a functionality with the 355 that I'm not understanding?
yes, if i remember the installation manual correctly but, by the time you install everything for the HSI, adding the AI is pretty much nothing.
the hsi is the bulk of the g5 system.

gi-275s are more independent
 
Well the plane already has two mechanical CDIs, one hooked up to my 300xl navcomm gps and the other to my ils/vor receiver. I also have a spare, unused cutout. My thought was to keep everything how it is, but install the 355 while adding the 275 HSI to the unused cutout, therefore having the 355 coordinate with the 275

Would that work? Or are you saying that the HSI can't also function as a CDI coordinating with the 355 gps?
Here’s a thought. You’re keeping this plane for a while. You have some old unsupported equipment that trying to stitch together is going to give you a somewhat unwieldy panel to scan and use.

I suggest this:

OPTION 1
-Garmin GNC-300XL NavComm
>>Remove, replace with Garmin GTN650. Tie it to one of your mechanical CDIs

-TKM MX11 Comm Receiver
>>Keep as second Com

-King KN-53 VOR-ILS NAV Receiver
>> I’d lean to taking it out as well as the second mechanical CDI.

-Garmin GTX 335 Transponder with ADS-B Out
>>>. Keep of course.
-External Sentry unit with Foreflight (iPad) for ADS-B IN
>>>. Keep

OPTION 2
Garmin GNC-300XL NavComm
>>> Remove, replace with GNC 355. Tie to one of your CDIs

-TKM MX11 Comm Receiver
>>> Keep as second Com

-King KN-53 VOR-ILS NAV Receiver
>>> Keep and tie to your second mechanical CDI

-Garmin GTX 335 Transponder with ADS-B Out
>>>>. Keep of course
-External Sentry unit with Foreflight (iPad) for ADS-B IN
>>>. Keep

Now, if you Really Really want a G275 (or a G5) HSI (also functions as a CDI) then put it where your current vacuum driven DG is, discard the old vacuum driven DG, and tie the new G275 HSI/CDI into your new GTN 650 or GNC 355.

There is no scenario that makes sense to keep your old vacuum driven DG and add a G275 HSI /CDI, especially when you’d want that new G275 HSI in the proper six pack location under the Attitude Indicator.
 
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Well the plane already has two mechanical CDIs, one hooked up to my 300xl navcomm gps and the other to my ils/vor receiver. I also have a spare, unused cutout. My thought was to keep everything how it is, but install the 355 while adding the 275 HSI to the unused cutout, therefore having the 355 coordinate with the 275

Would that work? Or are you saying that the HSI can't also function as a CDI coordinating with the 355 gps?
Yes, that would work.

However, you'll configure the GI275 as a CDI or as a HSI but not both. The difference in parts/labor is whether or not you order the ADAHRS version and whether or not a magnetometer is also installed. But if you get the ADAHRS version, you can leave the pitot/static/magnetometer/thermometer hookups unconnected, use it as a CDI for now and then move/reconfigure it as HSI below the (future) GI275 ADI later.

Which branch to take along the decision tree is going to depend on how you want to spread your budget.

A little tangent: I don't know your numbers, but I'd personally look hard at swapping the GTX335/Sentry for a GNX375.
 
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as your vor/nav is a seperate unit, i'd even think of installing a gnc355, keep the 300xl and the king. you really won't use vhf nav enough to bother with 2 and 1 will get you down in an emergency. oh yeah, even when you want to use vors for nav, most likely they will be notam'd out
2 gps, 2 comm, 1 vor/ils sounds great
 
as your vor/nav is a seperate unit, i'd even think of installing a gnc355, keep the 300xl and the king. you really won't use vhf nav enough to bother with 2 and 1 will get you down in an emergency. oh yeah, even when you want to use vors for nav, most likely they will be notam'd out
2 gps, 2 comm, 1 vor/ils sounds great
The GNC355 is GPS+COM and does not have a VLOC radio.

Which brings up an interesting point. No need for 3 COM, so if the OP wants to keep everything as it is and add a WAAS GPS then it should be a GPS175 and not a GNC355. Or swap out the GTX355/Sentry for a GNX375.
 
Here's a nice feature of a modern EFIS as an HSI. The magenta needles are the current GPS course (direct destination, which isn't actually going to happen given the wx).

Aircraft is already getting RVs to FAC for a simple LOC approach. The display is showing the current position of the LOC relative to the GPS course (which again is direct destination, but could be anything). Once the CDI button is pressed, the LOC needles go from grey to green. On the missed, if needed, you revert to magenta needles with another press of the button.

So I'd vote GTN650 and 275 HSI. That happens to be the setup driving the screen in the image. (The white needles are actually grey in real life.)

HSI275.jpg
 
The GNC355 is GPS+COM and does not have a VLOC radio.

Which brings up an interesting point. No need for 3 COM, so if the OP wants to keep everything as it is and add a WAAS GPS then it should be a GPS175 and not a GNC355. Or swap out the GTX355/Sentry for a GNX375.
I was thinking of dropping my secondary COMM and replacing it with the 355
 
Ask your avionics guy about his/her thoughts on the longevity, repairability of the 300XL.
 
Ask your avionics guy about his/her thoughts on the longevity, repairability of the 300XL.
In short, he's skeptical. His thought was keep it as a backup for now, and if we truly go forward with new avionics in the future we can swap it out during that install
 
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