Budget gps upgrade ?

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Bobby05

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Bobby05
I just bought a grumman cheetah with original 6 pack gauges. I was wondering if there is any budget friendly GPS and displays with cdi like the G5 or aspen units. The club plane I use to fly the owner put a aspen and garmin (not sure which model) and said the price was over $30K with installation. Is this about the normal price for a upgrade or can you get it done for alot cheaper? Im not looking for a full glass cockpit just the basic GPS unit with a digital attitude and cdi I could shoot RNAV approaches with. TIA
 
Bobby05 said:
I just bought a grumman cheetah with original 6 pack gauges. I was wondering if there is any budget friendly GPS and displays with cdi like the G5 or aspen units. The club plane I use to fly the owner put a aspen and garmin (not sure which model) and said the price was over $30K with installation. Is this about the normal price for a upgrade or can you get it done for alot cheaper? Im not looking for a full glass cockpit just the basic GPS unit with a digital attitude and cdi I could shoot RNAV approaches with. TIA
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A lot depends on what you already have in there. That said, a Garmin GPS175 and a pair of Garmin G5's will probably fit the bill.

Do you have any pictures of the existing panel?
 
budget friendly? In this hobby? That ship sailed with the rest of the monetary policy in 2020 ime.

As was mentioned, cheapest you can get that's still in production is the 175, and grab your ankles on labor anywhere you go, unless you roll your own wiring. Add more for G5 et al. If you come out under 20K in 2024 you're ahead. Like I said, 30K is outsized, but it's already within 10k of most installations you're asking about. Low economies of scale keeps the space sclerotic and unlikely to change. EAB would be cheaper, again if you discount the labor somehow. N/A for your captive audience with a fac-built. You should be able to get a quote under 20K for a 175 + G5. Good luck.
 
asicer said:
A lot depends on what you already have in there. That said, a Garmin GPS175 and a pair of Garmin G5's will probably fit the bill.

Do you have any pictures of the existing panel?
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I had the 175 and G5-HSI installed for $12K (equipment & labor) in 2020.
 
Dual G5s are hard to beat for reliability, redundancy, and cost for the EFIS. Depending on what you need, a GNS175 (GPS NAV only), GNC355(GPS/COM) or GNX375 (GPS/ADS-B Transponder) are probably the most budget-friendly options for GPS. You might be able to save on installation costs by using an independent installer who has experience putting in this equipment. I got dual G5s and an NGT-9000 installed and wired to my existing GNS-430 and STEC-20 autopilot for something like $3000 labor with a very good local independent installer. (That was a lot of new wiring and cleaning up of old garbage wiring.) Put the GMU-11 in the right wingtip in the AA-5X. Flying LPV approaches are ridiculously easy with dual G5s.
 
Post a pic of your panel.

For now, I’m assuming you have dual coms and nav’s with a mechanical CDI already. And you also have ADSB out.

If so, just get the GARMIN 175. It will drive your mechanical CDI. $8,000?

If you don’t have a CDI, buy a mechanical one for your new G 175. If you really want a digital, get the G 275 CDI version along with the G 175. $13,000 total?

You’ll be using your old attitude indicator. If you really want to replace that as well as your DG, get dual G 275s and the G175. $18,000 total?
 
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WDD said:
Post a pic of your panel.

For now, I’m assuming you have dual coms and nav’s with a mechanical CDI already. And you also have ADSB out.

If so, just get the GARMIN 175. It will drive your mechanical CDI. $8,000?

If you don’t have a CDI, buy a mechanical one for your new G 175. If you really want a digital, get the G 275 CDI version along with the G 175. $13,000 total?

You’ll be using your old attitude indicator. If you really want to replace that as well as your DG, get dual G 275s and the G175. $18,000 total?
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Yes sir it has dual comms and factory CDI. This may be the route i go and later on down the road go for the G5’s
 
Bobby05 said:
I just bought a grumman cheetah with original 6 pack gauges. I was wondering if there is any budget friendly GPS and displays with cdi like the G5 or aspen units. The club plane I use to fly the owner put an aspen and garmin (not sure which model) and said the price was over $30K with installation. Is this about the normal price for an upgrade or can you get it done for alot cheaper? Im not looking for a full glass cockpit just the basic GPS unit with a digital attitude and cdi I could shoot RNAV approaches with. TIA
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Depending on the choice of hardware, that price isn’t off by much. The GI275s are more costly, but you are getting hardware that will be supported longer, better display, and other nice features.
 
Bobby05 said:
Here’s what I’m working with
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Hm, starting from the top of the radio stack looks like Narco MK12D NAV/COM, TKM MX11 COM, Narco DME-890, Collins RCR-650 ADF and Narco AT50 transponder. Over on the left are a Narco ID-825 CDI, Narco NAV11 all-in-one VOR/LOC/indicator (no glide scope) and Collins IND-650 (ADF). Above those are an audio panel hiding in the shadows, maybe a Narco CP125?

I'd swap the ADF, transponder, AI and DG with with a Garmin GNX375 and a pair of G5's. The NAV/COM/DME stuff are varying degrees of useful while the ADF is not. Old Narco stuff can be delicate and if the transponder dies then you could be grounded depending on where you fly. Yanking out the vacuum system and ADF equipment are probably the biggest reductions in empty weight.
 
with your setup i'd install a gnx 375 and use the existing indicator. should be reasonable in price, nothing is cheap in aviation these days.
now if you want to start getting into glass, that's where it'll get difficult real fast

gi-275s are great but can only be installed by garmin avionics shop, usually.
they are so flexible you can use one for almost any purpose from simple cdi/moving map thingy to adi/hsi/engine monitor etc....

g5's are great, bit dumbed down from the 275's but set you up nicely for a future g3x upgrade. they can be purchased over the counter and installed by any a&p or you can do yourself with supervision.
 
MackMooney said:
i'd install a gnx 375 and use the existing indicator.
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Except for the ID-825, you can't use any of the existing indicators. And there are several reasons you don't want to use the ID-825, one of which is that you'd disable the MK12D and DME.
 
Could I just get a g175 or 355 and it run off my factory gauges for now and later on down the road get the G5’s ? I mainly want it for I can shoot rnav approaches and ads-b out/in which I think I’d have to get the 355 for that I have a Ads-b out that’s in the tail beacon at the moment.
 
Bobby05 said:
Could I just get a g175 or 355 and it run off my factory gauges for now and later on down the road get the G5’s ? I mainly want it for I can shoot rnav approaches and ads-b out/in which I think I’d have to get the 355 for that I have a Ads-b out that’s in the tail beacon at the moment.
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you need the gnx375 for adsb out/in. gnc175 = gps. gnc355 = gps/comm. gnx375 = gps/transponder/adsb.
I'm guessing your main indicator, the one with ILS would be compatible, check with an avionics shop

also looking at the placement of the radios, without a new cdi/g5/gi275, you'll probably need an annunciator panel
 
Bobby05 said:
Could I just get a g175 or 355 and it run off my factory gauges for now and later on down the road get the G5’s ?
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GPS175 is a WAAS GPS.
GNC355 is a GPS175 with built-in COM radio.
GNX375 is a GPS175 with a transponder and ADSB-In and ADSB-Out.

Each of those are 2 inches tall. The Collins RCR 625 ADF is 1.8 inches tall. Unless there's a spare quarter-inch or so, something else needs to come out.

With any of the GPS175/GNC355/GNX375, you could get a used GI-106 CDI for around $1000. It's probably the best low-dollar solution because it is resolver-based. You could go cheaper by getting a composite-based CDI or even trying to re-use yours, but cost difference is only a few hundred dollars and there are usability issues.

If budget is that tight, makes me wonder what you'll do if your oil cooler springs a leak, your transponder gives out, you get a flat tire away from home, etc.
 
If $ are pretty tight, you can find a clean 400W WAAS for $2K. You can probably find a guy working on the side to install it for $1500 +/-. That'll ad a pretty decent capability for the least amount of money.

I LOVE my 175, but it was $9K installed. I have two giant G3X Touch screens, however...so I don't have to mess with the tiny screen hardly ever. I've spent so much time behind the 400 series, I'm comfortable with them and would have no issues using one for another decade.
 
asicer said:
If budget is that tight, makes me wonder what you'll do if your oil cooler springs a leak, your transponder gives out, you get a flat tire away from home, etc.
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Reminds me of the senior enlisted nonners [and their lame duck O-6 supervisors] who think my apathy towards worn/UV-faded patches and scuffed boots in my duty uniform is indicative of lack of proficiency or trustworthiness in the conduct of my primary duty.

Don't conflate $ willingness with ability. Though it may be a distinction without difference to vendors, it isn't in the context of what you're insinuating. The accusation "people unwilling to approach discretionary spending with the same inelasticity as government approaches Rx drug pricing, are nothing but unworthy interlopers", is as old as time. In fairness, nobody ever accused this hobby of being an example of democratized leisure...

bigmo said:
clean 400W WAAS for $2K. You can probably find a guy working on the side to install it for $1500 +/-.
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Why shouldn't he be able to do that with your 175? It's not like the unit is dealer-locked.
 
You keeping this plane for a long time - 10 years or so?
 
The CP125 is ill suited for modern avionics. Mine turned into a proper audio panel (Garmin GMA340) when I did my GNS430 upgrade. PS Enginering makes really nice audio panels, too. I did my panel upgrade in three stages: (1) audio panel, GNS430, and GI106A CDI, (2) STEC-20 autopilot, (3) dual G5s and NGT-9000 transponder. (GI-106A and vac system removed.) Stage 4 will be a replacement of the legacy NAVCOM2, which will allow me to repurpose the GI-106A.
 
bigmo said:
If $ are pretty tight, you can find a clean 400W WAAS for $2K.
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I can't see installing a GNS 4xx navigator now. If the screen fails, they will be unrepairable, if not already, in the very near future. If you already have one, run it in the ground and replace it with an IFD440 when it dies. While the GNS430 is capable and robust, the tech is quite old now.
 
Ditto on not installing the GNS.

After looking at the picture of the panel, I’d say take out the ADF tuner and your old transponder as well as the ADF instrument. Put in a GNX 375 and a replace your current CDI with a used GI-106 CDI per Asicer. Remove and sell whatever you’re using for ADSB out.

You might need a third party switch to toggle between VLoc and GPS for the GI 106.
 
WDD said:
You might need a third party switch to toggle between VLoc and GPS for the GI 106.
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The GI-106 will be dedicated to the GNX375, so no switch needed. The MK12D is already connected to the ID-825 CDI and the NAV11 is a CDI with a built-in VLOC (or a VLOC with a built-in CDI, depending on your point of view).
 
Ok. In that case get rid of the Nav11 and replace with the GI 106. Just have 2 CDIs in total.
 
WDD said:
Ok. In that case get rid of the Nav11 and replace with the GI 106. Just have 2 CDIs in total.
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But then how to do the 30 day VOR check?

The plane already has 3 CDI CDI/bearing indicators, 2VLOC + 1ADF. Replacing the ADF with a GI-106 will keep it at 3.
 
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A set of three CDIs is not useful use of panel space IMHO. Two is more than enough. There are other ways to check VOR’s every 30 days.

95% of IFR flying will be GPS and LPV approaches. Seems a waste of panel space to have two Nav radio only CDIs that will hardly ever be used.
 
WDD said:
There are other ways to check VOR’s every 30 days.
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Your profile says you're at KRYY. How would you do the check without two radios?
1. VOT - the chart supplement says there's none in Georgia.​
2. VOR checkpoint - except for KRMG, they're all >100nm away. And RMG is currently NOTAM'ed​
3. Find a landmark along a Victor airway - not too many near KRYY. And they reference RMG, which is currently NOTAM'ed.​
​
With 2 radios, you just tune them to AHN, sign the log and you're done.

Also, the OP did mention budget. It'll cost extra to remove something that doesn't have to be removed.
 
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so the part that makes this extra difficult. us IR guys are paranoid to the extreme, we need backups for the backups and an out when that backup takes a ****. A waas gps pretty much renders the vor system completly obsolete, you will not use it except out of nostalgia or some infrequent emergency. that being said, watch a solar flare come and take out all the satellites tomorrow. ILS is not VOR and doesn't require a check, meaning you may never need or bother checking the equip.

so personally, i maintain my two full nav/comms even though i never use the equip.
 
MackMooney said:
A waas gps pretty much renders the vor system completly obsolete, you will not use it except out of nostalgia or some infrequent emergency.
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So how would you get into KWEA without a VOR check?
 
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MackMooney said:
so the part that makes this extra difficult. us IR guys are paranoid to the extreme, we need backups for the backups and an out when that backup takes a ****. A waas gps pretty much renders the vor system completly obsolete, you will not use it except out of nostalgia or some infrequent emergency. that being said, watch a solar flare come and take out all the satellites tomorrow. ILS is not VOR and doesn't require a check, meaning you may never need or bother checking the equip.

so personally, i maintain my two full nav/comms even though i never use the equip.
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100% confirm. I can't remember the last time I used a VOR to navigate in the last 20 years after installing WAAS GPS. I religiously do my VOR checks when I remember, but the reality I only use the ILS capabilities of my NAV/COMs. If IFR, your most important backup is probably not VORs, but your COMs. IF GPS craps out, VORs are cold comfort, because most every one in my region has been decommissioned or is out of service. I might not be able to get home via VOR if I wanted to. But I could use ATC vectors to get to an ILS (assuming they are functional--a bunch of them in my area are also out of service.)
 
chemgeek said:
100% confirm. I can't remember the last time I used a VOR to navigate in the last 20 years after installing WAAS GPS. I religiously do my VOR checks when I remember, but the reality I only use the ILS capabilities of my NAV/COMs. If IFR, your most important backup is probably not VORs, but your COMs. IF GPS craps out, VORs are cold comfort, because most every one in my region has been decommissioned or is out of service. I might not be able to get home via VOR if I wanted to. But I could use ATC vectors to get to an ILS (assuming they are functional--a bunch of them in my area are also out of service.)
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How would you get into KLZD without a VOR check?
 
I see Nav VOR navigation as emergency back up. Having one is fine. If you can’t find an active VOR anywhere in your area to check the Nav receiver then you’ve answered the question on how much panel space it deserves

Given he has to make some space I. The panel to put the new GNX 375 hell gave to take something out - this take out the useless ADF as well as the old transponder.
 
asicer said:
How would you get into KLZD without a VOR check?
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I wouldn't, i'd probably just go to one of the airports within 20 miles with an rnav/ils/etc... I mean there are hundreds of airports without approaches to begin with, not truly worried about a couple odd balls
 
But if he has a local AM station close by, at least he could find his way there with the adf.
 
MackMooney said:
I wouldn't, i'd probably just go to one of the airports within 20 miles with an rnav/ils/etc... I mean there are hundreds of airports without approaches to begin with, not truly worried about a couple odd balls
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There's also situations of convenience. Let's say you're arriving KONM from the north. To shoot the RNAV, you'd have to fly to the Socorro VOR, fly 32 miles to HETUD, do a HILPT and then fly 13 miles back. Or you could just shoot the VOR approach from ONM.

(There was another where you could either shoot a straight-in VOR approach or you could fly 20 miles out, execute a 10 mile DME arc and then fly 20 miles back, but unfortunately I forgot to note the airport.)

Edit: Another one is KEMT. VOR approach is from the east. RNAV approach is from the west and NA for westbound arrivals. If you have to go elsewhere then you're spending an hour in stop-and-go traffic on an LA freeway.
 
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asicer said:
There's also situations of convenience. Let's say you're arriving KONM from the north. To shoot the RNAV, you'd have to fly to the Socorro VOR, fly 32 miles to HETUD, do a HILPT and then fly 13 miles back. Or you could just shoot the VOR approach from ONM.

(There was another where you could either shoot a straight-in VOR approach or you could fly 20 miles out, execute a 10 mile DME arc and then fly 20 miles back, but unfortunately I forgot to note the airport.)
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In real life, i skipped it and landed at KROW, couldn't miss seeing all the aliens 8)

if i knew i was flying to that airport and wanted to use the vor approach, i'd check my equip via an alternate means. i'd probably have checked the vor equip via alternate means anyway because again, i'm a paranoid IR guy.

really looking at KONM, the mins on the vor approach are pretty high, i'd probably only consider, if it's already VFR and I need help finding the airport. crappy weather, i'm taking the rnav
 
MackMooney said:
In real life, i skipped it and landed at KROW, couldn't miss seeing all the aliens 8)

if i knew i was flying to that airport and wanted to use the vor approach, i'd check my equip via an alternate means. i'd probably have checked the vor equip via alternate means anyway because again, i'm a paranoid IR guy.

really looking at KONM, the mins on the vor approach are pretty high, i'd probably only consider, if it's already VFR and I need help finding the airport. crappy weather, i'm taking the rnav
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The KEMT situation (VOR approach is from the east. RNAV approach is from the west and NA for westbound arrivals.) is probably one of the more realistic scenarios.
 
that one is a bit interesting, i could ask for vectors on the RNAV to atleast make it shorter then circle to land. or even better, i can use my waas gps to get me to an IAF, then do my vor check from a known point at that location 8). honestly, i'd have just checked my equip prior to needing those approaches
 
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